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He, Chunmei. "GEOTECHNICAL CHARACTERIZATION OF LUNAR REGOLITH SIMULANTS." Cleveland, Ohio : Case Western Reserve University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1269272964.
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Thesis (Doctor of Philosophy)--Case Western Reserve University, 2010Department of Civil Engineering Title from PDF (viewed on 2010-05-25) Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
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Gharib, Nima. "Investigating regolith induced wear and dust mitigation." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121357.
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"There is growing international interest in space exploration. Going back to the moon where we will build a sustainable long-term human presence with new spacecraft, robotics and life-sustaining technologies, will prepare humans for future exploration of other planets in our solar system and asteroids and for space mining" [1]. The moon will serve as a base to develop and test new technologies, experience living on an extraterrestrial surface and will provide clues about the origin of the universe. Returning to the moon however, is not easy. The harsh lunar environment, solar radiation, the large amplitude of the temperature fluctuation and the negligible atmosphere and therefore low atmospheric pressure will challenge future manned and unmanned missions. One of the most pervasive limits to lunar surface exploration is the presence of lunar dust, which is electrostatically charged and adheres to everything with which it comes into contact. Lunar dust is very fine and also highly abrasive [2]. In this work, two abrasive wear test devices were designed and manufactured to study the volume wear rate of different materials when subjected to lunar dust simulant of different size ranges. There were three additional objectives to this research. First, the potential of using electrostatic and dielectrophoretic forces to remove and transport small particles away from surfaces was investigated by manufacturing several devices comprising series of parallel electrodes connected to single or multiple AC power source(s). The traveling electric field created then served as an invisible brush to clean surfaces and prevent dust from entering joints in space applications (e.g. bearing, solar panels, camera, etc.). Second, discrete element models were created and calibrated based on the experimental results to study the capacity of this technique to clean dust from surfaces in the lunar environment. Third, evaluated the idea of sorting and transporting regolith (i.e., the loose, heterogeneous material covering solid rock) into the journal bearing (i.e., a plain bearing designed to reduce friction by supporting radial loads) and employing it as a solid lubricant. Experimental outcomes demonstrate satisfactory performance of the electric curtain in terms of dust removal from surfaces, with low power consumption. They also indicate the need for standardization of wear and abrasion tests for space applications at low temperature and pressure. One recommendation resulting from this research is investment by the Canadian Space Agency on infrastructure and equipment such as "dirty chambers" to enable performance of similar experiments in dusty moon-like environments. This research was conducted with support from an NSERC Collaborative Research and Development Grant involving Neptec Design Group, the Canadian Space Agency, and McGill University."L'exploration spatiale est en pleine expansion dans la communauté internationale. En retournant à la lune où nous construirons une présence humaine à long terme qui soit durable avec des nouveaux vaisseaux spatiaux, des robots et des technologies pour maintenir la vie durable. C'est aussi à nous préparer pour future exploration des autres planètes de notre système solaire, des astéroïdes, et l'exploitation minière spatial" [1]. La lune servira comme une base pour développer et tester des nouvelles technologies, faire l'expérience de vivre dans un environnement extraterrestre, et fournir des indices sur l'origine de l'univers. Cependant retourner sur la Lune n'est pas une tache facile. Les conditions extrêmement difficile de l'environnement lunaire, les dangereuses rayonnements solaire, les variations de températures et l'espace vide mettra nos futures missions, avec ou sans astronautes, en danger. L'un des plus grands défis que nous rencontrerons au cours de l'exploration de la surface de la lune est la poussière lunaire qui est éléctrostatiquement chargé et adhérera tout ce qui entre en contact avec. La poussière est très fine et très abrasif aussi [2]. Dans cette étude, trois appareils ont été conçus et deux d'entre eux ont été construites afin d'examiner la quantité de particules qui retire du matériel pendant l'expérience d'abrasion par la poussière lunaire a diamètre variable. Également la possibilité d'utiliser des forces électrostatiques et diélectrophoetique pour enlever et transporter des petites particules des surfaces ont été étudié par plusieurs dispositifs en fabricant des compositions d'électrodes parallèles qui sont connecté à une source d'alimentation unique ou multiple AC. Le champ électrique qui se déplace sert alors comme un pinceau invisible pour nettoyer les surfaces et évite la poussière de pénétrer dans les joints des applications spatiales (par exemple les instruments qui roulent, les panneaux solaires, les appareils photo, etc.). En plus de cela, des modèles DEM ont été créés et calibrés sur la base des résultats expérimentaux pour étudier la capacité de cette technique pour nettoyer la poussière des surfaces dans l'environnement lunaire. En outre, l'idée de regrouper et de transporter le régolithe dans un palier lisse et l'employer comme un lubrifiant solide a été souligné. Les résultats des expériences montrent une performance satisfaisante du rideau électrique en termes de dépoussiérage des surfaces avec une faible consommation électrique. Ils suggèrent également la nécessité d'une standardisation des expériences abrasive pour les applications spatiales à faible température et pression. Une proposition par rapport aux résultats obtenu dans cette recherche est l'investissement de l'Agence Spatiale Canadienne sur les infrastructures et les équipements tels que "Les chambres sale" afin d'être en mesure de réaliser des expériences similaires dans des environnements poussiéreux comme la surface de la lune. Cette recherche est menée dans le cadre d'une subvention du CRSNG CRD entre Neptec Design Group, l'Agence Spatiale Canadienne et l'Université McGill.
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Curran, Natalie. "Unravelling the history of the lunar regolith." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/unravelling-the-history-of-the-lunar-regolith(9b80ec12-db98-44c7-824d-5f170e4ae3c1).html.
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The lunar regolith is sensitive to the bombardment history of the Moon and contains a wealth of knowledge regarding the types of processes that have modified the lunar crust through time. Noble gases that are produced and trapped in the lunar regolith, as a result of this interaction with the space environment, can be used to determine the cosmic ray exposure age, maturity, shielding depth and antiquity age of lunar regolith samples. This thesis aims to probe this temporal archive to further understand the impact history of the Moon contained within the regolith. Initially, all the published noble gas literature data for the Apollo regolith breccias, drill cores and soils was compiled into a database where trapped and cosmogenic noble gas component were calculated. These data were used to summarise the history of the lunar regolith contained in the Apollo sample archive. A dichotomy between the "ancient" (determined by the antiquity indicator using the 40Ar/36Artr ratio) regolith samples and those formed in more recent times has been described previously (e.g., McKay et al., 1986).The ancient breccias and soils (>~3.5 Ga) have typically experienced limited amounts of surface exposure (i.e., they are 'immature'). Whereas, regolith samples formed in more recent times ( < 3.5 Ga, << 2 Ga) show a range of maturities. It is likely that the difference in maturity between the ancient and younger breccias reflects the changing collisional conditions of the time i.e., impact flux and regolith turnover rates. Here, 12 lunar meteorite regolith breccias were analysed for their noble gas content (Ne, Ar, Xe isotopes) to determine if lunar meteorites show the same difference between (40Ar/36Ar)tr ratio and maturity. Lunar meteorites in this study and previously published data do show the same negative correlation between (40Ar/36Ar)tr ratio and maturity. Furthermore, many of the lunar meteorite samples have (40Ar/36Ar)tr ratio between 1 and 2.5 indicating antiquity ages of approximately 1-2 Ga. This potentially reflects a declining period of random intermediate impacts bracketing the period between the 'ancient' and 'recent' samples. The same techniques were applied to newly discovered lunar meteorite MIL 13317. This included a full petrology description, mineral chemistry, U-Pb and Pb-Pb ages, and analysis of noble gas content to decipher the regolith history of this new sample. The meteorite is a mixture of mare and highland components (including mare basalts, FAN, Mg-suite and KREEP) with ancient ages (~ 4.3Ga) and a complex regolith history (exposure age ~500 to 800 Ma, antiquity age ~1.92 Ga). MIL 13317 is an important addition to the lunar collection as it contains material from previously unsampled areas of the Moon which is interpreted here to be associated with the northern regions of the Procellarum KREEP Terrane. Work was also begun on Apollo 16 regolith breccias using the same analytical techniques. However, due to instrument issues and friable samples much of the work was not completed and will be continued after the PhD. Understanding the data collected here and the techniques used will feed forward to future missions to the Moon to understand noble gas concentrations in the lunar regolith.
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Meurisse, Alexandre [Verfasser]. "Solar 3D Printing of Lunar Regolith / Alexandre Meurisse." München : Verlag Dr. Hut, 2018. http://d-nb.info/1162768061/34.
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Meurisse, Alexandre René Jacques [Verfasser]. "Solar 3D Printing of Lunar Regolith / Alexandre Meurisse." München : Verlag Dr. Hut, 2018. http://d-nb.info/1162768061/34.
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Warell, Johan. "Regolith Properties of Mercury Derived from Observations and Modelling." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://publications.uu.se/theses/91-554-5535-2/.
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Singh, Mandeep. "Construction technique and strength of connected regolith bag structures." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Theses/SINGH_MANDEEP_3.pdf.
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Marks, Alan Stephen. "Remote sensing of the regolith, Shoalwater Bay area, Queensland." Thesis, Canberra, ACT : The Australian National University, 1993. http://hdl.handle.net/1885/140068.
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Grundström, Billy. "Additive manufacturing of lunar regolith simulant using direct ink writing." Thesis, Uppsala universitet, Tillämpad materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-418249.
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In this work, the use of a lunar regolith simulant as feedstock for the direct ink writing additive manufacturing process is explored, the purpose of which is to enable future lunar in-situ resource utilisation. The feasibility of this approach is demonstrated in a laboratory setting by manufacturing objects with different geometries using methyl cellulose or sodium alginate as binding agents and water as liquid phase together with the lunar regolith simulant EAC-1A to create a viscous, printable ‘ink’ that is used in combination with a custom three-axis gantry system to produce green bodies for subsequent sintering. The sintered objects are characterised using compressive strength measurements and scanning electron microscopy (SEM). It is proposed that the bioorganic compounds used in this work as additives could be produced at the site for a future lunar base through photosynthesis, utilising carbon dioxide exhaled by astronauts together with the available sunlight, meaning that all the components used for the dispersion – additive, water (in the form of ice) and regolith – are available in-situ. The compressive strength for sintered samples produced with this method was measured to be 2.4 MPa with a standard deviation of 0.2 MPa (n = 4). It is believed, based on the high sample porosity observed during SEM analysis, that the comparatively low mechanical strength of the manufactured samples is due to a non-optimal sintering procedure carried out at a too-low temperature, and that the mechanical strength could be increased by optimising the sintering process further.
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Dunker, Philip A. "A Biologically Inspired Robot for Lunar Exploration and Regolith Excavation." Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1219803272.
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Agustin, Fitriani. "Mapping the regolith and its mineralogy of the Tick Hill region, Mount Isa, Queensland, using Hymap and ASTER remote sensing data." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/27.
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The study involved investigating the use of ASTER and HyMap datasets from the Tick Hill area, Mount Isa region in Queensland, to make mineral maps and validate them, and subsequently to use the mineral maps to map and study the regolith-landforms. The processing techniques used on the multispectral and hyperspectral data were relative band depth (RBD) and Spectral Indices, and a sequence of masking procedures to minimize spectral overlap effects from other materials such as vegetation, atmospheric particles and minerals. The ASTER datasets allowed mapping of mineral groups such as Al-OH, Mg-OH and iron oxides rather than individual mineral maps. HyMap data, due to its better spectral resolution was able to map kaolinite, kaolinite crystallinity, iron oxides (hematite and goethite), white mica, Mg-OH + carbonate minerals, and to an extent silica and Al-smectite.The application of the mineral maps applied to map regolith-landforms allowed better characterization of regolith materials as compared to traditional band combination methods. Surface mineralogy could be linked to specific surface regolith materials such as kaolinite and iron oxides representing ferruginous materials (duricrusts, soils or mottled zones), abundance of well crystalline kaolinite equated to saprolite and mottled saprolite and high Mg-OH equated to slightly weathered (saprock) exposures of Pre-Mesozoic basement rocks. Spatial variation in mineralogy permitted interpreting changes in surface regolith and refining regolith-landform units as mapped from simple Red-Green-Blue band combinations. Kaolinite crystallinity maps were effective in highlighting in situ regolith from transported regolith, and allowing interpretation of the presence of deep weathering profiles being capped by ferruginous materials (duricrusts) or saprolite exposures on the hills, rises and erosional plain landforms of the regions.
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Laffan, Shawn William, and Shawn Laffan@unsw edu au. "Inferring the Spatial Distribution of Regolith Properties Using Surface Measurable Features." The Australian National University. School of Resources, Environment and Society, 2001. http://thesis.anu.edu.au./public/adt-ANU20040714.155019.
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The aim of this research is to determine to what extent properties of the regolith may be inferred using only features easily measured from the surface. To address this research question, a set of regolith properties from Weipa, Queensland, Australia, are analysed. The set contains five variables, oxides of Aluminium, Iron, Silica and Titanium, as well as Depth to Ironstone. This last represents the depth of the layer from which the oxides are sampled.¶ The research question is addressed in two ways. First, locations where the properties are related to modern surface hydrology are assessed using spatially explicit analyses. This is done by comparing the results of spatial association statistics using geometric and watershed-based spatial samples. Second, correlations are sought for between the regolith properties and geomorphometric indices of land surface morphology and Landsat Thematic Mapper spectral response. This is done using spatially implicit Artificial Neural Networks (ANN) and spatially explicit Geographically Weighted Regression (GWR). The results indicate that the degree to which regolith properties are related to surface measurable features is limited and spatially variable.¶ Most locations in the Weipa landscape exhibit some degree of modern hydrological control of the oxide variables at lateral distances of 120 m. This control rarely extends beyond 300 m laterally, although such locations occupy distinct positions in the landscape. Conversely, there is an extensive part of the landscape where Depth to Ironstone is under hydrological control. This occupies most of the lower elevations in the study area. Depth to Ironstone represents the depth to the redox front where iron is precipitated, but may in some parts of the landscape control the distribution of the watertable by being impermeable.¶ For the correlation analyses, the highest correlations are found with those oxides most mobile in solution. The spatially local GWR results also consistently outperform the spatially global ANN results, commonly having accuracies 40% higher at the error tolerance used. Much of this can be attributed to the localized effects of landscape evolution. Comparison of the GWR results against the local sample mean indicate that there is a relationship between regolith properties and surface measurable features at 10-15% of sample locations for the oxide variables, and 22% for Depth to Ironstone.¶ The implications of these results are significant for anyone intending to generate spatial datasets of regolith properties. If there is a low spatial density of sample data, then the effects of landscape evolution can reduce the utility of any analysis results. Instead, spatially dense, direct measurements of subsurface regolith properties are needed. While these may not be a direct measurement of the property of interest, they may provide useful additional information by which these may be inferred.
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Ackerman, Benjamin R. "Regolith geochemical exploration in the Girilambone District of New South Wales." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20051027.095334/index.html.
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Bell, Julie Dee. "Properties and genesis of regolith: a workingmodel for Hong Kong hillslopes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45015284.
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Martin, Dayl. "IR spectroscopy of planetary regolith analogues, lunar meteorites, and Apollo soils." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/ir-spectroscopy-of-planetary-regolith-analogues-lunar-meteorites-and-apollo-soils(366e3992-f823-4e88-8c5c-0fcea1d25fe8).html.
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The main objectives of this study are to determine how various physical and chemical properties of geologic samples can be investigated by Fourier Transform InfraRed (FTIR) spectral analyses, and determine how each of these individual properties uniquely alter the mid-infrared spectrum. Of particular interest is how extraterrestrial samples differ (spectrally) from terrestrial samples, and how such findings can be applied to current and future missions to airless planetary bodies (such as Diviner Lunar Radiometer, aboard the Lunar Reconnaissance Orbiter, and the Mercury Thermal Radiometer on BepiColombo). As such, a range of geological samples have been analysed including terrestrial rocks (anorthosite, granite, grabbro etc.), mineral standards (common rock-forming minerals), lunar meteorites (from Miller Range, Antarctica), and Apollo 14, 15, and 16 soils. A new technique to analyse such samples has been developed and implemented as part of this study: FTIR spectral imaging of unconsolidated samples (powders and soils) to obtain modal mineralogy estimates. Such estimates are comparable to QEMSCAN analyses and spot point counting of the same samples. This is particularly relevant for the non-destructive analysis of Apollo soil samples (bulk and sieved fractions). Individual spectra of polished terrestrial and extraterrestrial samples have been obtained in preparation for the creation of a spectral database. Such samples also have coupled chemical composition information via Electron Probe MicroAnalysis (EPMA). To have a spectrum and an associated chemical composition for each mineral in a database is unique compared to other spectral databases. Analyses of lunar meteorites resulted in an understanding of how shock (caused by hypervelocity impacts) alters the physical and spectral properties of lunar minerals. FTIR microscopy of individual minerals and phases in the meteorites were coupled with optical and cathodoluminescence (CL) imaging to identify the level of shock obtained by each mineral and phase. The FTIR reflectance bands of plagioclase merge with increasing shock pressure until a single, low-reflectance broad peak is displayed by the most highly shocked plagioclase (>45 GPa), and a dark-red colour is present in CL images. FTIR and QEMSCAN analyses of Apollo regolith samples have provided an understanding of the spectral effects of bulk mineralogy, maturity (a measure of the time spent at the lunar surface), grain size, and mineral chemistry. Using such information, the modal mineralogy of each sample has been estimated, one of which had not previously been analysed for its modal mineralogy. Samples from the same Apollo missions present similar spectral features, meaning FTIR spectroscopy can be used to identify the origin of lunar soils. A weak correlation in maturity with a spectral feature termed the Christiansen Feature has been found for lunar samples. Related to maturity, FTIR spectra of individual agglutinates (a product of space weathering) have been obtained and the spectral properties of agglutinates (decreased %Reflectance values of the region sensitive to geological materials) resemble those of highly mature lunar soils.
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Snape, J. F. "Studies of the petrologic and geochemical diversity of the lunar regolith." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1381931/.
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This study comprises petrologic investigations of the lunar meteorite Northeast Africa (NEA) 001 and 16 fragments from the Apollo 12 soil 12003. These samples are examples of the variety of materials found in lunar feldspathic highland and mare regoliths, and provide insights into the petrogenesis of different lithologies and regolith mixing processes. They have been analysed by electron microprobe and laser ablation inductively coupled plasma mass spectrometry. NEA 001 is a feldspathic regolith breccia containing clasts of multiple lithologies including; feldspathic impact melt, ferroan noritic anorthosite, magnesian feldspathic clasts and low-Ti and very-low-Ti (VLT) basalts. Feldspathic impact lithologies in NEA 001 are more mafic than estimations for the composition of the upper feldspathic lunar crust, indicating that they have incorporated more mafic lower crustal material. The VLT basalt clasts have low incompatible trace elements (ITE) concentrations, and may represent products of primitive basaltic volcanism. The feldspathic nature of the sample, low-ITE concentrations, and the presence of magnesian feldspathic clasts suggest that the meteorite has been sourced from the Outer-Feldspathic Highlands Terrane, probably on the lunar farside. Apollo 12 landed in the eastern region of Oceanus Procellarum. Previous studies of Apollo 12 samples identified three major basaltic suites (olivine, ilmenite and pigeonite basalts) local to the region. Examples of all three of these have been identified within the 12003 soil collected near the Lunar Module. Two samples are identified as possibly representing a previously unrecognised basaltic suite. One sample is identified as a possible addition to the feldspathic suite; a potential fourth basaltic suite currently consisting of only one other sample. Three non-igneous samples are identified, including two breccias and one impactite. The petrologic analysis of these samples forms part of an ongoing basaltic diversity study which will also include radioisotope dating of these and other Apollo 12 soil samples.
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Dalrymple, Iain Faculty of Science UNSW. "An approach to the optimisation of partial extractions for use in geochemical exploration." Awarded by:University of New South Wales, 2007. http://handle.unsw.edu.au/1959.4/40473.
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Geochemical exploration for mineral deposits has generally been restricted to regions dominated by residual regolith or where transported regolith cover is thin. A variety of partial geochemical extraction techniques, linked to new predictive models for element migration through transported regolith cover, have demonstrated a potential to detect deeply buried mineralisation under certain circumstances. Problems with the reliability and further development of such partial extractions are linked to the lack of information on either the form of metals or the factors that control the extraction of metals from regolith materials. This study quantitatively examines the mechanisms of a range of partial extraction methods, based on a suite of surface regolith samples from the Mandamah Cu-Au deposit that is covered by 50m of transported regolith. Samples at were subjected to acetate, hydroxylamine.HCI and Na-pyrophosphate extractions at various reagent concentrations, pH values, temperatures and durations, following various sample preparation and chemical pretreatment permutations. The data were modelled, and reaction conditions subsequently optimized, on the basis of central composite designs. Conventional partial extraction (acetate, hydroxylamine and aqua regia) data, displayed high variability for some major and trace metals surrounding the periphery of mineralisation at Mandamah but little indication of direct vertical migration of ore-related metals. The buffered acetate extraction is primarily controlled by the capacity of the solution to generate acid rather than exchange induced by the cation ofthe acetate salt. Trace metals were highly susceptible to readsorption effects. Acidic hydroxylamine extraction is driven by kinetically limited acid hydrolysis and the hydroxylamine concentration has little effect on metal extractability. Alkaline Na-pyrophosphate extraction proved difficult to model. Two new partial extractions developed in this study - alkaline hydroxylamine.HCI and pH-static calcium nitrate - offer a different functionality to conventional extractions and provide more coherent geochemical patterns at Mandamah related to the location of buried mineralisation. These patterns are also related to the capacity of samples to resist pH neutralization. Systematic optimisation of geochemical extraction procedures is demonstrated to be an effective approach to improving detection of geochemical patterns in surface regolith that can be spatially related to the effects of mineralisation on the chemistry and mineralogy of overlying transported regolith cover.
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Bell, Julie Dee. "Properties and genesis of regolith : a working model for Hong Kong hillslopes /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36585208.
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Smith, Martin Lancaster. "Towards a geochronology for long-term landscape evolution, Northwestern New South Wales /." View thesis entry in Australian Digital Theses Program, 2006. http://thesis.anu.edu.au/public/adt-ANU20061026.141414/index.html.
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Smith, Martin Lancaster, and martin smith@anu edu au. "Towards a Geochronology for Long-term Landscape Evolution, Northwestern New South Wales." The Australian National University. Research School of Earth Sciences, 2006. http://thesis.anu.edu.au./public/adt-ANU20061026.141414.
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The study area extends from west of the Great Divide to the Broken Hill and Tibooburra regions of far western New South Wales, encompassing several important mining districts that not only include the famous Broken Hill lodes (Pb-Zn-Ag), but also Parkes (Cu-Au), Peak Hill (Au), Cobar (Cu-Au-Zn) and White Cliffs (opal). The area is generally semi-arid to arid undulating to flat terrain covered by sparse vegetation.
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During the Cretaceous, an extensive sea retreated across vast plains, with rivers draining from the south and east. After the uplift of the Great Divide associated with opening of the Tasman Sea in the Late Cretaceous, drainage swung to the west, cutting across the Darling River Lineament. The Murray-Darling Basin depression developed as a depocentre during the Paleogene. Climates also underwent dramatic change during the Cenozoic, from warm-humid to cooler, more seasonal climates, to the arid conditions prevalent today. Up until now, there has been very little temporal constraint on the development of this landscape over this time period. This study seeks to address the timing of various weathering and landscape evolution events in northwestern New South Wales.
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The application of various regolith dating methods was undertaken. Palaeomagnetic dating, clay δ18O dating, (U+Th)/He and U-Pb dating were all investigated. Palaeomagnetic and clay dating methods have been well established in Australian regolith studies for the last 30 years. More recently, (U+Th)/He dating has been successfully trialled both overseas and in Australia. U-Pb dating of regolith materials has not been undertaken. Each method dates different regolith forming processes and materials. Palaeomagnetic and clay dating were both successfully carried out for sites across northwestern New South Wales, providing a multi-technique approach to resolving the timing of weathering events. Although (U+Th)/He dating was unsuccessful, there is scope for further refinement of the technique, and its application to regolith dating. U-Pb dating was also unsuccessfully applied to late-stage anatase, which is a cement in many Australian silcretes.
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Results from this study indicate that the landscape evolution and weathering history of northwestern New South Wales dates back at least 60 million years, probably 100 million years, and perhaps even as far back as 180 million years. The results imply that northwestern New South Wales was continuously sub-aerially exposed for the last 100 Ma, indicating that marine sedimentation in the Murray-Darling and Eromanga-Surat Basins was separated by this exposed region. The ages also provide further evidence for episodic deep chemical weathering under certain climatic conditions across the region, and add to the data from across Australia for similar events. In particular, the palaeomagnetic ages, which cluster at ~60 ± 10 Ma and 15 ± 10 Ma, are recorded in other palaeomagnetic dating studies of Australian regolith. The clay ages are more continuous across the field area, but show older clays in the Eromanga Basin sediments at White Cliffs and Lightning Ridge, Eocene clays in the Cobar region, and Oligocene Miocene clays in the Broken Hill region, indicating progressively younger clay formation from east to west across northwestern New South Wales, in broad agreement with previously published clay weathering ages from around Australia.
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These weathering ages can be reconciled with reconstructions of Australian climates from previously published work, which show a cooling trend over the last 40 Ma, following an extended period of high mean annual temperatures in the Paleocene and Eocene. In conjunction with this cooling, total precipitation decreased, and rainfall became more seasonal. The weathering ages fall within periods of wetness (clay formation), the onset of seasonal climate (clay formation and palaeomagnetic weathering ages) and the initiation of aridity in the late Miocene (palaeomagnetic weathering ages).
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This study provides initial weathering ages for northwestern New South Wales, and, a broad geochronology for the development of the landscape of the region. Building on the results of this study, there is much scope for further geochronological work in the region.
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Gibbons, Lisa Karen. "Regolith study of the Old Well gold prospect, Tarcoola District, Gawler Craton /." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09SB/09sbg4417.pdf.
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Ogunyinka, Adebayo Olutumbi. "Investigation Of Material Properties Of Sintered Black Point-1 Lunar Regolith Simulant." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/30886.
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The quest for establishing a human presence and development beyond the Earth, especially on the moon has opened up opportunities for future plans for lunar bases and settlements. However, the cost of using resources outside the lunar environment can inhibit this form of expansion, therefore the need for In Situ Resource Utilization (ISRU). The aim of this research was to investigate the possible usage of in situ resources for lunar construction and other economic development. The study evaluated different methods of material preparation using lunar regolith simulant for structural applications on the moon. The research employed the use of the regolith simulant known as Black Point-1 (BP-1). This research work presents the methodology used in developing lunar simulant and compares the properties of BP-1 regolith simulant to those of lunar soil, in terms of geotechnical and mechanical properties. Various laboratory analyses were carried out to determine these properties with the aid of thermal and analysis, particle size distribution, and XRD experiments. Our findings show that the particle size distribution and porosity of BP-1 are similar to that of the lunar regolith. The simulant was then sieved to produce four grades of powder (38 µmm, 106 µm, 212 µm and unsieved). The graded powders were then compressed to form a series of disc-shaped green compacts for sintering. The sintered samples were then subjected to compression testing. There were four different values of average compressive strength of the porosity materials ranging from lowest to highest porosity corresponding to the smallest to largest average grain sizes of 38 µm, 106 µm, unsieved and 212µm and they were 66.14MPa, 60.47MPa, 58.52MPa, 42.74 MPa, respectively. The particle size distribution was investigated on Black Point-1 simulant to determine the effect of the porosity while the bulk properties of the material were also examined for each of the four porosity grades, and this includes toughness, Poisson ratio, bulk modulus, Young’s modulus of elasticity and compressive strength. When compared with other ISRU structural materials and published data for real lunar regolith it was observed that sintered BP-1 is sufficiently strong for lunar structural applications.
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Carte, David Brad. "The REgolith X-ray Imaging Spectrometer flight model : structural design, analysis, and testing." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98805.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 177-181).
Engineers of space flight programs face unique technical challenges created by the space environment in which these systems operate. High costs and increasing complexity of space programs create a greater demand for mission reliability. This demand further drives up development costs and project time lines. The result is that few missions are flown and few organization are able to participate in space program development. Project budget and schedule overruns are in part a result of a risk-averse culture and the desire the create fail-proof systems. Resource constrained programs will have difficulty developing successful space systems if they attempt to fully address every risk. Rather, by taking a risk-tolerant posture, resource-constrained programs can more efficiently allocate resources to the most important areas of a system's development. By focusing effort and resources on high-risk areas, successful space programs can still be developed with lower budgets and smaller schedules than has traditionally been done. Recent attempts to lower the time and budgets necessary to develop space systems have focused on developing smaller, less complex, and more numerous space system to replace traditionally larger, more expensive systems. The benefits of small space systems range from distributing risk across multiple systems and thereby lowering the cost of failure, to providing smaller organizations and universities the capabilities to develop their own space systems. Though these programs are cheaper, many organizations of small space systems are faced with limited resources that must be intelligently allocated to develop successful space programs. This thesis presents the structural design, analysis, and testing of the REgolith Xray Imaging Spectrometer (REXIS), a student-led instrument on board the National Aeronautics and Space Administration (NASA) Origins Spectral Interpretation Resource Identification and Security-Regolith Explorer (OSIRIS-REx) asteroid sample return mission. As part a student experiment, the REXIS team must develop its system under tight resource constraints. The limited funding, personnel, equipment, and facilities available to the REXIS team all have important implications on how design, analysis, and testing decisions are made on REXIS. This thesis provides a discussion of key areas of the REXIS structural development and lessons learned from a structural engineering point of view. Chapter 1 opens the discussion by talking about the motivation behind this thesis. It provides background information to the REXIS instrument and the context for the rest of the instrument discussion. The REXIS flight structural design and how this design facilitates the accomplishment of REXIS goals is presented in Chapter 2. Next, the analysis and testing of the Radiation Cover, one of REXIS's most critical elements, is described in Chapter 3. The key efforts taken on the REXIS structural development is discussed in Chapter 4. This particular section, through the discussion of the chronological development of the REXIS flight structural design, will highlight important areas of where efforts was focused on REXIS within the project constraints. Lastly, Chapter 5 provides lessons learned from a structural engineering point of view from the experiences on REXIS. Although the discussion focuses on the REXIS structural development, the examples and discussions described are relevant to other programs. This thesis is meant to provide insight into the REXIS development from which engineers of future small space programs can learn.
by David Brad Carte.
S.M.
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Schreiner, Samuel Steven. "Molten Regolith Electrolysis reactor modeling and optimization of in-situ resource utilization systems." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98589.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 161-170).
In-Situ Resource Utilization (ISRU), the practice of leveraging space resources to support space exploration, has long been considered as a possible avenue for reducing the mass and cost of exploration architectures. In particular, producing oxygen from lunar regolith holds great promise for maintaining life support systems and enabling orbital refueling of chemical propulsion systems to reduce launch vehicle mass. Unfortunately, significant uncertainty as to the mass, power, and performance of such ISRU systems has prohibited a rigorous quantitative analysis. To this end, parametric sizing models of several ISRU systems are developed to better understand their mass, power, and performance. Special focus is given to an oxygen production technique, called Molten Regolith Electrolysis (MRE), in which molten lunar regolith is directly electrolyzed to produce oxygen gas and metals, such as iron and silicon. The MRE reactor model has a foundation of regolith material property models validated by data from Apollo samples and regolith simulants. A coupled electrochemical and thermodynamic simulation is used to provide high-fidelity analysis of MRE reactor designs. A novel design methodology is developed that uses data from the simulation to parametrically generate mass, volume, power, and performance estimates for an MRE reactor that meets a set of performance criteria. An integrated ISRU system model, including an MRE reactor, power system, excavator, liquid oxygen storage system, and other systems, is leveraged in a hybrid optimization scheme to study the optimal system design and performance characteristics. The optimized models predict that a 400 kg, 14 kW MRE-based ISRU system can produce 1,000 kg oxygen per year from lunar Highlands regolith. A 1593 kg, 56.5 kW system can produce 10,000 kg oxygen per year. It is found that the optimal design of an MRE-based ISRU system does not vary significantly with regolith type, demonstrating the technique's robustness to variations in regolith composition. The mass and power of the optimized ISRU system exhibit an economy of scale, indicating that larger quantities of oxygen can be produced more efficiently. In fact, the production efficiency estimates of a lunar ISRU system provide initial evidence that lunar ISRU may prove beneficial in supporting a Mars Exploration campaign.
by Samuel Steven Schreiner.
S.M.
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Valle, Lozano Aaron. "Development of a Lunar Regolith Thermal Energy Storage Model for a Lunar Outpost." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-59941.
Full textAbstract:
The Moon has always been an important milestone in space exploration. After the Apollo landings, it is logical to think that the next step should be a permanent habitation module, which would serve as a testing ground for more ambitious projects to Mars and beyond. For a lunar base to come into realization, it is necessary to assess a number of technological challenges which are due to the harsh conditions that can be found on the Earth's satellite. One of these tasks revolves around energy storage: During the day it is possible to use photovoltaic cells and convert the solar irradiance into electrical energy to power an outpost, however during the lunar night this source is not available. Current investigations establish that the optimal landing site for a permanent mission would be on the rim of the Shackleton crater, near the South Pole. This would reduce the night duration from 14 days to 52 hours of the lunar cycle, which is 29.5 days. While this significantly decreases the exposure to the cold temperatures of the Moon when there is no sunlight, there is still a need for a system to provide energy to the lunar base over this period. Therefore, this study pretends to serve as a possible solution for the aforementioned problem, by developing a system storing energy as thermal energy and then harvesting it as electricity using thermoelectrics. First, a theoretical introduction is presented, where the problem statement is exposed, along with background information regarding the solar illumination and the lunar soil. At the same time, an insight on regolith sintering techniques is given. These techniques are important as a means to providing thermal energy storage during the night cycle. After this, the core of the study is developed: The ideal system for energy storage is broken down into segments, and each of them is explained attending to the possible requirements of a lunar base, while providing supporting simulations when deemed appropriate. These are the solar concentrator, thermal mass, thermoelectric array, cold sink and, if necessary, a pipe network. Following this chapter, a device is proposed. Based on the previously mentioned guidelines, an ideal thermal energy system is simulated and evaluated. Although it is not optimized for efficient energy harvesting, it serves as insight on the design and simulation constraints that appear when one wants to collect electrical energy from thermoelectrics with relatively low efficiency. It was estimated that the prototype would output a mean power of 3.6 Watts over the whole duration of the lunar night. Although in its current state this technology would not present significant benefits over existing energy storage methods such as nickel-hydrogen batteries, this study also proposed several optimization methods which could vastly increase the performance of the device. These include adding more efficient thermoelectric patterns, or modifying the properties of the semiconductors by doping or using nanostructures, and present follow-on opportunities for further research.
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Standish, Evan C. "Design of a Molten Materials Handling Device for Support of Molten Regolith Electrolysis." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1268975211.
Full text
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Sargent, Sara. "Radiation Shielding Bricks for Mars Using Martian Regolith Simulant and Hydrogen-Rich Polymers." W&M ScholarWorks, 2018. https://scholarworks.wm.edu/etd/1550153774.
Full textAbstract:
Radiation shielding materials are an essential component of long-term space travel and habitation. The mission to Mars will require a radiation shielding material that can be produced on Mars through energy and cost-efficient means. in this study, Martian regolith simulant and hydrogen-rich polymers are used to create a radiation shielding material in the form of bricks. The bricks are capable of shielding against galactic cosmic radiation on Mars. There are three methods in which the bricks were formed: 1) a heated press, 2) a microwave oven in a CO2 atmosphere, and 3) a vacuum oven with a low CO2 pressure. Each brick varies by the type of polymer, percent of polymer, and the method in which it was made. Flexural tests were conducted on the bricks to determine the flexural strength, flexural strain, and modulus of elasticity. OLTARIS was used to estimate the effectiveness of these bricks to shield against GCR on the Martian surface.
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Weinmann, Julian. "Influence of the Martian regolith on the atmospheric methane and water vapour cycle." Thesis, Luleå tekniska universitet, Rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-75897.
Full textAbstract:
Context. The Martian methane and water cycle are subject of ongoing research through simulation. Exchange with the subsurface has a potentially strong impact, but is often neglected. Aims. For methane, I determine if adsorption with an increased enthalpy can explain the observed seasonal variations and conflicting observations by the Trace Gas Orbiter and the Curiosity rover. For water, the impact of adsorption and ice formation in the subsurface on the global cycle is studied. A new way of initializing the soil, by running a decoupled subsurface model, is tested. Depths of stable subsurface ice and subsurface water distributions are studied. Methods. A General Circulation Model (GCM) is used with a purely diffusive subsurface model. For methane, different initial states, source scenarios, and decay times are tested. For water, a model without an active atmosphere is implemented to provide an initial state. The effect of the subsurface with this initial state on the full atmospheric water cycle is tested. Results. For methane, a strong influence on the global methane cycle is observed. Seasonal variations measured at Gale Crater are reproduced, but the conflicting observations cannot be explained by adsorption. For water, the new initialization can be used without completely disrupting the water cycle. It leads to a generally wetter atmosphere, in conflict with observations. Found ice table depths do not match well with observations, but ice profiles reproduce previous findings. Conclusion. Methane adsorption is able to partly explain observed variations, but cannot be the only process to influence methane abundances. The new initialization method for water works well in principle, but a more refined model is needed for more realistic results.
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Castillo, betancourt Juan Pablo. "Thermo-mechanical properties of a regolith simulant of the mars insight mission site." Electronic Thesis or Diss., Marne-la-vallée, ENPC, 2023. https://these.univ-paris-est.fr/intranet/2023/TH2023ENPC0035.pdf.
Full textAbstract:
La mission Mars InSight de la NASA est une mission Discovery visant à étudier l'intérieur de la planète rouge, et par conséquent à aider à la compréhension de son processus de formation et de celui des autres planètes telluriques. L'un des nombreux fronts d'étude auxquels est confrontée l'équipe scientifique de la mission InSight est l'étude des propriétés du matériau situé en contact direct avec l'atterrisseur et ses instruments, dont certains ont été déployés à la surface de la planète via l'utilisation d'un bras robotique. Cet effort est le but du groupe de travail Near Surface Working Group (NSWG), et les travaux et résultats présentés dans ce document est de fournir des informations pour aider cet objectif de recherche. L'atterrisseur utilise trois instruments principaux pour atteindre ses objectifs scientifiques : le premier est le Seismic Experiment for Interior Structure (SEIS), un sismomètre de haute précision résultant de plusieurs décennies d'efforts menés par des institutions françaises, dont le Centre National des Études Spatiales CNES et l’Institut de Physique du Globe de Paris IPGP ; cet instrument est le plus pertinent pour ce travail. Le deuxième est le Heat and Physical Properties Package (HP3), une sonde thermique conçue pour forer l’intérieur de la surface martienne jusqu’à des profondeurs allant jusqu’à 5 m. La dernière est l'antenne Rotation and Interior Structure Experiment ou RISE, qui étudie la structure intérieure de la planète à l'aide du mouvement de rotation de Mars, en suivant la position de l'atterrisseur et le déplacement du pôle Nord de la planète pour proposer des modèles de son moment d’inertie. Ce travail consiste en plusieurs activités de recherche dans le domaine de la mécanique des sols, réalisées dans le but de caractériser le matériau situé à la surface de l'atterrisseur Mars InSight de la NASA, installé sur Elysium Planitia depuis novembre 2018. Il s'agit principalement d'essais expérimentaux dans un analogue de régolithe martien et quelques activités complémentaires. Les questions clés abordées étaient l'interaction du SEIS avec le régolithe martien de surface en contact direct avec ses trois pieds, la faible rigidité en déformation de ce matériau (comportement en gamme élastique), ainsi que certaines questions spécifiques telles que la conductivité thermique et l’effet des fluctuations de la pression atmosphérique. Les travaux expérimentaux menés représentent notamment une connaissance précieuse dans le monde peu exploré de la mécanique des sols sous de très faibles contraintes et déformations (le plus souvent inférieures à 50 kPa). La préparation des échantillons est une autre question explorée, puisque les densités les plus faibles possibles de l’analogue du régolithe sont utilisées en cherchant à se rapprocher le plus possible des conditions du matériau sur Mars. Le travail de thèse a été développé dans le cadre d'une cotutelle entre l'Université des Andes et l'École des Ponts ParisTech. Les travaux expérimentaux ont été menés dans les installations des deux institutions de recherche et ont été rendus possibles grâce à l'expertise du groupe de recherche et de l'équipe technique affiliée à chaque université et ses laboratoires. Ce document contient une synthèse des points clés de chacun de ces travaux. Certaines collaborations avec la doctorante Maria Juliana Chaparro ont également permis d'évaluer les propriétés dynamiques du matériau analogue du régolithe choisiThe NASA Mars InSight mission is a Discovery mission aiming at to investigating the interior of the red planet to support the understanding of its formation process and that of other rocky planets. One of the many study fronts faced by the InSight Mission Science Team is the study of the properties of the material in direct contact with the lander and its instruments, some of which were deployed on the surface of the planet by using a robotic arm. This endeavour is the key objective of the Near Surface Working Group (NSWG), and the main goal of the different works and results presented in this document is related to this research goal. The lander uses three main instruments: the first one is the Seismic Experiment for Interior Structure (SEIS), a highly accurate seismometer resulting from decades of work by French institutions including Centre National des Études Spatiales CNES and Institut de Physique du Globe de Paris IPGP; this instrument is the most relevant for this work. The second one is the Heat and Physical Properties Package (HP3), a thermal probe designed to drill inside the Martian surface to depths of up to 5m. The last one is the Rotation and Interior Structure Experiment or RISE antenna, which studies the interior structure of the planet aided by the rotation movement of Mars, tracking the position of the lander and the shifting of the planets north pole to propose models of its moment of inertia.This work is aimed at characterising the surface regolith properties at the site of the Mars InSight lander, landed on Elysium Planitia since November 2018. This comprises experimental investigations on a Martian Regolith Simulant together with some complementary activities. The key questions addressed were the interaction of the SEIS with the Martian regolith in direct contact with its three feet, its very small strain stiffness (in the elastic range), as well as the thermal conductivity and the mechanical effect of atmospheric pressure fluctuations. The experimental work conducted concerns the poorly explored field of soil mechanics under very low stresses and strains (down to 1.75 kPa). Sample preparation is another question explored, since the loosest possible densities of the regolith analogue are utilised to mimic the Martian regolith.The thesis was developed within a joint supervision between the Universidad de los Andes (Bogota, Colombia) and the École des Ponts ParisTech (France). Experimental work was conducted at the facilities of both institutions. A collaborations with PhD student Maria Juliana Chaparro (Los Andes) also helped assess the dynamic properties of the regolith simulant
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Holzapfel, Michael, and n/a. "Regolith-landform mapping and dryland salinity investigaton: Booberoi-Quandialla Transect, Western New South Wales." University of Canberra. Resource, Environmental & Heritage Sciences, 2004. http://erl.canberra.edu.au./public/adt-AUC20060519.144945.
Full textAbstract:
Landholders in the Booberoi to Quandialla (B-Q) Transect area, located in central west
NSW, have been concerned about an emerging dryland salinity problem since the late
1990�s (Wooldridge 2002, pers. comm. Muller 2002, pers. comm.) with borehole
information and electromagnetic induction investigations supporting anecdotal
observations. The presence of indicator vegetation, waterlogging of soils and
salinisation of land are becoming increasingly prevalent, with two well-documented
sites including �Strathairlie� near Quandialla, and �Back Creek� near West Wyalong.
The B-Q Transect area lies within the Bland Creek Catchment, a broad open plain of
subdued topography and restricted drainage receiving sediments from elevated rises
located to the west, south and east. Significant deposits of transported alluvial materials
have in-filled the catchment to depths in excess of 160 m and have posed a particular
impediment to regional-scale mineral exploration. Stream flow across the alluvial
plains and low angle alluvial fans is intermittent with most of the flow being diverted
into groundwater storage or lost to evaporation. Rarely do streams flow into Lake
Cowal to the north.
A partial electromagnetic (EM) induction survey coupled with a long term bore and
piezometer network monitoring program have been implemented by the Department of
Infrastructure, Planning and Natural Resources (DIPNR � formerly Department of Land
and Water Conservation) Central West NSW Salt Group. These programs allow for
initial, broad-scale evaluation of the magnitude and spatial distribution of the salinity
problem but fail to pinpoint remaining sites at risk as well as the mechanisms of salt
emplacement.
As part of an approach to assist with hazard mitigation and land management, two
regolith-landform maps are being compiled using 1:20,000 scales in the Back Creek and
Quandialla areas. A third, more regional regolith-landform map at 1:50,000 scale
(Holzapfel & Moore 2003a, b & c) provides context for the more detailed mapping
areas. The new regolith-landform maps will aid in interpretation of existing geophysical
techniques, help piece together the three-dimensional characteristics of the Bland Creek
catchment, aid in the development of a shallow fluid flow and palaeotopographic model
and assist land managers in formulating land management units (LMU�s).
The three-dimensional integration of regolith-landform mapping, electromagnetic
studies, bore information and other geophysical methods is critical in determining the
interaction, distribution and movement of groundwater in the Bland Creek Catchment as
buried palaeochannels represent preferred fluid pathways. The distribution of these
palaeochannels has implications for future dryland salinity outbreaks, the remediation of
current outbreaks and mineral exploration closer to the well-known Wyalong Goldfield
(Lawrie et al., 1999).
The western quarter of the B-Q Transect area partially overlaps with the recently
completed GILMORE Project (Lawrie et al., 2003a,b & c), a multi-disciplinary study,
coordinated by Geoscience Australia (GA) and the Bureau of Rural Sciences (BRS).
Regolith-landform information in addition to gamma-ray spectrometry, magnetics,
airborne electromagnetics and a digital elevation model acquired by the GILMORE
Project have been incorporated into regolith-landform maps over the B-Q Transect. The
incorporation of these datasets has helped not only extend the usefulness of the
GILMORE Project data but provide a consistent, regolith-landform coverage for the
broader Bland Creek Catchment.
Regolith-landform mapping has been successful in highlighting major recharge zones
for local and intermediate flow systems. The mechanisms for dryland salinity at two
well-known sites have also been determined. Increasing salt stores are occurring
through evaporation of intermittent floodwaters sourced from floodplains, back plains
and broad meandering existing creek systems and recharging partially exposed
palaeochannels intersecting the surface. Due to the shallow nature of these partially
exposed palaeochannels, evaporation further concentrates the salt load in the soil
profile. It is unknown if mapped shallow palaeochannels further away from current
drainage systems are affected by rising salt loads.
Regolith-landform mapping highlights two additional risk factors common to the
1:50,000 and 1:20,000 scale B-Q Transect mapping areas including widespread
waterlogging of soils and wind erosion. Due to the subdued topography, features such
as gilgai, fences and roads are having an effect on drainage modification. Wind erosion
was also observed to play a major role within the B-Q Transect with significant loss of
topsoil creating hardened clay surfaces resistant to water infiltration and significant
redistributed deposits of aeolian materials.
Interpretation of regolith-landform mapping against geophysical datasets and drill hole
data show considerable lateral and vertical variation of regolith units. This variation of
regolith distribution with depth does not reduce the effectiveness of using regolithlandform
mapping as a valued management tool. The subdued relief coupled with the
complex interplay between recharge zones, discharge zones and surficial drainage
networks over the B-Q Transect still requires a detailed knowledge of surface regolithlandform
characteristics whilst reinforcing the need for a multidisciplinary approach to
gain a 3D perspective.
Catchment analysis has been performed on drainage systems within the Bland Creek
Catchment and has helped explain the strong effect different catchments have had on
sediment supply to the Bland Basin. Catchment analysis results have been used in basic
calculations of salt loads in the Bland Creek Catchment. An estimated 18,780 Tonnes/yr
of salt enter the Bland Creek catchment and as stream flow out of the Bland Creek
Catchment is intermittent, salt stores are increasing in the upper margins of the soil
profile and groundwater reserves.
Reconstruction of the palaeotopography of the B-Q Transect has been made possible
using a mutli-disciplinary approach incorporating information from regolith-landform
mapping, drill hole information, gamma-ray spectrometry and GILMORE Project
datasets. The production of large-scale regolith-landform mapping, the development of
a shallow fluid flow model and reconstruction of palaeotopography builds on and
contributes to knowledge of the Bland Creek Catchment allowing for detailed farmscale
and paddock-scale land management decisions.
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Brunskill, Christopher. "Trafficability characterisation of planetary regolith analogues for the mobility assessment of low-mass microrovers." Thesis, University of Surrey, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616938.
Full textAbstract:
The use of mobile robots has formed the core of numerous exploration missions to the Moon and Mars. However, estimation of rover traction on the loose, granular regolith found widely on the lunar and martian surfaces remains challenging. While it is relatively easy to describe the forces imparted on the terrain by a rover, characterisation of the terrain response and its trafficability has proven to be more difficult. The validation of future rover designs and laboratory-based experiments to aid current mission operations will rely on a comprehensive understanding of the deformation mechanics of regolith-like materials. This thesis presents a novel terrain characterisation methodology and analysis which extends current approaches to trafficability analysis using the theory of terramechanics. The presented approach primarily focuses on identifying the effects of changes in relative density on the deformation behaviours of frictional soils under low loading conditions. Motivated by previous work that produced Surrey Space Centre (SS C) regolith simulants, a study of in-situ martian and lunar regolith properties is presented. A classification method by particle size distribution (PSD) is demonstrated and three Engineering Soil (ES) simulants suitable for use with the ExoMars rover testbed are selected based on the PSD. Preparation and characterisation methods are developed to provide samples of each simulant at three discrete relative densities and measure their shear and normal load failure responses. Finally, these data are used to study the trafficability characteristics of two simulants using a simple microrover single wheel testbed. Direct shear tests using samples of the ES simulants demonstrated little sensitivity in the residual stress to initial density. However, the magnitude of the simulant brittleness (the brittleness index) was found increase with PSD under low loading conditions similar to those of the ExoMars rover. Furthermore, the sensitivity of the brittleness index to sample density demonstrated that the measured residual stress does not reflect the critical state strength in high PSD simulants. Subsequent pressure-sinkage tests demonstrated that failure planes developed due to normal load do not reflect the residual strength of the soil. Therefore, where brittleness index is greater than approximately 33 %, the standard Bekker/ReeceWong pressure-sinkage curves do not fully capture the normal failure response. By splitting the pressure-sinkage data into pre- and post-failure regions, parameter goodness of fit was found to improve by up to 13% in high brittleness ES-3. A more modest improvement of up to 3% was seen in the lower brittleness SSC- 2. Using these parameters, model performance predictions were computed and compared with preliminary single wheel testbed data. While the precision of the data support the presented methodologies, future improvements to the apparatus and additional data will aid in verifying the accuracy of these measurements. Keywords: terramechanics, soil mechanics, traction, microrovers, pressuresinkage, regolith, frictional soils, soil simulants, plastic failure, brittle failure, relative density
32
Beckett, Kirsty A. "Multispectral analysis of high spatial resolution 256-channel radiometrics for soil and regolith mapping." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/1434.
Full textAbstract:
Over the past decade studies into the application of radiometrics for soil and regolith mapping have met with mixed response. While the use of radiometric data for regolith mapping has been generally well received, radiometric methods have not commonly been adopted to assist and improve soil mapping. This thesis contributes to the development of radiometric techniques as soil and regolith mapping tools by examining soil characteristics and radiometric response using non-standard radiometric methods. This is accomplished through the development of new data processing methodologies, which extracts additional information from standard radiometric data that is unattainable using standard processing methods, and development of a new interpretation approach to soil and regolith mapping employing the multispectral processed radiometric data. The new multispectral processing methodology resolves seven gamma ray peaks from standard 256-channel NaI radiometric data to produce new radiometric uranium ternary, thorium ternary and uranium ratio imagery. Changes in the gamma ray relationships, identified through the new imagery, identify changes in soil and/or environmental conditions that are absent or difficult to identify in the standard radiometric imagery. With the isolation of non-standard thorium channels 228 [superscript] Ac (900 keV) and 228 [superscript] Ac (1600 keV), case studies in this thesis demonstrate how the difference of 1.9 years (half-life) between thorium 228 [superscript] Ac and 232 [superscript] Th decay daughter products can be mapped through the interpretation of thorium energy using ternary imagery [red: 208 [superscript] Tl (1764 keV), green: 228 [superscript] Ac (900 keV), blue: 228 [superscript] Ac (1600 keV)]. Energy peak differences may be be linked to local variations in soil chemistry, soil movement, and water movement.Additionally, through the isolation of non-standard uranium channels 214 [superscript] Bi (1120 keV) and 214 [superscript] Bi (1253 keV), preferential attenuation of lower energy gamma-rays from 214 [superscript] Bi decay events are exploited to map variations in soil density and/or porosity. These variations are illustrated through the interpretation of uranium energy using ternary imagery [red: 214 [superscript] Bi (1764 keV), green: 214 [superscript] Bi (1120 keV), blue: 214 [superscript] Bi (1253 keV)] and uranium peak energy ratio [214 [superscript] Bi 1120 keV / 214 [superscript] Bi 1764 keV] pseudo colour imagery. Case studies examined in this thesis explore the characteristics of 256-channel radiometric spectrum from different resolution datasets from different Western Australian soil types, provide recommendations for acquiring radiometric data for soil mapping in different agricultural environments, demonstrate how high resolution 256-channel radiometric data can be used to model soil properties in three-dimensions, and illustrate how three-dimension soil models can be used to separate surface waterlogging influences from rising groundwater induced waterlogging.
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Beckett, Kirsty A. "Multispectral analysis of high spatial resolution 256-channel radiometrics for soil and regolith mapping." Curtin University of Technology, Dept. of Exploration Geophysics, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17703.
Full textAbstract:
Over the past decade studies into the application of radiometrics for soil and regolith mapping have met with mixed response. While the use of radiometric data for regolith mapping has been generally well received, radiometric methods have not commonly been adopted to assist and improve soil mapping. This thesis contributes to the development of radiometric techniques as soil and regolith mapping tools by examining soil characteristics and radiometric response using non-standard radiometric methods. This is accomplished through the development of new data processing methodologies, which extracts additional information from standard radiometric data that is unattainable using standard processing methods, and development of a new interpretation approach to soil and regolith mapping employing the multispectral processed radiometric data. The new multispectral processing methodology resolves seven gamma ray peaks from standard 256-channel NaI radiometric data to produce new radiometric uranium ternary, thorium ternary and uranium ratio imagery. Changes in the gamma ray relationships, identified through the new imagery, identify changes in soil and/or environmental conditions that are absent or difficult to identify in the standard radiometric imagery. With the isolation of non-standard thorium channels 228 [superscript] Ac (900 keV) and 228 [superscript] Ac (1600 keV), case studies in this thesis demonstrate how the difference of 1.9 years (half-life) between thorium 228 [superscript] Ac and 232 [superscript] Th decay daughter products can be mapped through the interpretation of thorium energy using ternary imagery [red: 208 [superscript] Tl (1764 keV), green: 228 [superscript] Ac (900 keV), blue: 228 [superscript] Ac (1600 keV)]. Energy peak differences may be be linked to local variations in soil chemistry, soil movement, and water movement.Additionally, through the isolation of non-standard uranium channels 214 [superscript] Bi (1120 keV) and 214 [superscript] Bi (1253 keV), preferential attenuation of lower energy gamma-rays from 214 [superscript] Bi decay events are exploited to map variations in soil density and/or porosity. These variations are illustrated through the interpretation of uranium energy using ternary imagery [red: 214 [superscript] Bi (1764 keV), green: 214 [superscript] Bi (1120 keV), blue: 214 [superscript] Bi (1253 keV)] and uranium peak energy ratio [214 [superscript] Bi 1120 keV / 214 [superscript] Bi 1764 keV] pseudo colour imagery. Case studies examined in this thesis explore the characteristics of 256-channel radiometric spectrum from different resolution datasets from different Western Australian soil types, provide recommendations for acquiring radiometric data for soil mapping in different agricultural environments, demonstrate how high resolution 256-channel radiometric data can be used to model soil properties in three-dimensions, and illustrate how three-dimension soil models can be used to separate surface waterlogging influences from rising groundwater induced waterlogging.
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Lau, Ian Christopher. "Regolith-landform and mineralogical mapping of the White Dam Prospect, eastern Olary Domain, South Australia, using integrated remote sensing and spectral techniques." Title page, abstract and table of contents only, 2004. http://hdl.handle.net/2440/37972.
Full textAbstract:
The research contained within this thesis was directed at examining the spectral properties of regolith-dominated terrains using airborne and proximal hyperspectral instruments. The focus of the investigation was to identify the mineralogy of the regolith and determine if surficial materials were indicative of the underlying bedrock in the regolithdominated terrain of the eastern Olary Domain, South Australia. The research area was constrained to a 250 km2 area around the Cu-Au mineralisation of the White Dam Prosect. Integrated remote sensing, using airborne hyperspectral datasets (HyMap), Landsat imagery and gamma-ray spectroscopy data, was performed to map regolith-landforms and extract information on surficial materials. Detailed calibration of the HyMap dataset, using a modified model-based/empirical line calibration technique, was required prior to information extraction. The White Dam area was able to be divided into: alluvial regolith-dominated; in situ regolith-dominated; and bedrock-dominated terrains, based on mineralogical interpretations of the regolith, using the remotely sensed hyperspectral data. Alluvial regions were characterised by large abundances of vegetation and soils with a hematite-rich mineralogy. Highly weathered areas of in situ material were discriminated by the presence of goethite and kaolinite of various crystallinities, whereas the bedrock-dominated regions displayed white mica-/muscovite-rich mineralogy. Areas flanking bedrock exposures commonly consisted of shallow muscovite-rich soils containing regolith carbonate accumulations. Traditional mineral mapping processes were performed on the HyMap data and were able to extract endmembers of regolith and other surficial materials. The Mixture Tuned Matched Filter un-mixing process was successful at classifying regolith materials and minerals. Spectral indices performed on masked data were effective at identifying the key regolith mineralogical features of the HyMap imagery and proved less time consuming than un-mixing processes. Processed HyMap imagery was able to identify weathering halos, highlighted in mineralogical changes, around bedrock exposures. Proximal spectral measurements and XRD analyses of samples collected from the White Dam Prospect were used to create detailed mineralogical dispersion maps of the surface and costean sections. Regolith materials of the logged sections were found to correlate with the spectrally-derived mineral dispersion profiles. The HyLogger drill core scanning instrument was used to examine the mineralogy of the fresh bedrock, which contrasted with the weathering-derived near-surface regolith materials. The overall outcomes of the thesis showed that hyperspectral techniques were useful for charactering the mineralogy of surficial materials and mapping regolith-landforms.Thesis (Ph.D.)--School of Earth & Environmental Sciences, 2004.
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Akinyemi, Segun Ajayi. "Optimisation of selective extraction techniques as a tool for geochemical mapping in the Southern Africa region." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_3444_1260521237.
Full textAbstract:
The complex nature and composition of regolith cover in Southern Africa is a major challenge to geochemical mapping for concealed mineralization. Some of the setbacks to successful geochemical exploration may be ascribed to the use of various partial extraction techniques,without a profound understanding of the regolith components and their composition. This investigation therefore focuses on the use of hydroxylamine partial extraction geochemistry for geochemical mapping in regolith over two contrasting environments viz
aeolian sand-calcrete regolith over Au mineralization at Amalia Blue Dot Mine in South Africa and lateritic regolith covering the Ni-Cu deposit at Kabanga Main and Luhuma in Tanzania. Regolith samples from the above areas were sieved and extracted with hydroxylamine hydrochloride solution and analyzed for multi-element by AAS and ICP-MS techniques. A stepwise optimization of the hydroxylamine extraction technique of samples from both areas was carried out and incorporated into the analytical programme (in a pilot study). Results of hydroxylamine partial extraction generally gave better anomaly contrast and reflection of bedrock mineralization than the conventional aqua regia techniques that were previously used in the region. The results however show that lateritic regolith may be best extracted using 0.25M hydroxylamine while 0.1M concentration appears most suitable for extraction of aeolian-calcrete regolith. The above results are corroborated by principal component analysis of the analytical data that show various element associations, e.g. with Fe-Mn oxides while others possibly belong to the loosely adsorbed or exchangeable group. The
gochemical maps in the pilot study areas at Amalia, Kabanga and Luhuma show elevated element contents or clusters of anomalies of diverse elements associated with Fe-Mn oxides. Geochemical mapping at Kabanga with deeply concealed mineralization however shows variability of subdued element patterns over mineralized areas. Geochemical signatures associated with hydroxylamine hydrochloride partial leach are therefore characterized by a lower geochemical background than that using conventional aqua regia leach. This study leads recommending for further investigations into partial extraction of the exchangeable group of elements, possibly using ammonium acetate.
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Jamali, Imran Ali. "Subsurface dams in water resource management : methods for assessment and location." Doctoral thesis, KTH, Mark- och vattenteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-181937.
Full textAbstract:
Natural groundwater storage can be improved by constructing a subsurface barrier that is a subsurface dam, in order to capture the subsurface flows and raise the groundwater levels (GWLs) in the sediment layers. Subsurface dams are preferable to surface dams because of lower evaporation, higher functionality, lower cost of construction, lessened risk for contamination and the possibility of utilizing land over the dam. Therefore subsurface dams constitute an affordable and effective method for the sustainable development and management of groundwater resources. The aim of this research project was to develop and test methods for the assessment and location of subsurface dams in water resources management. From previous experiences it has been established that locating suitable sites for construction of subsurface dams plays an important role in the overall success of these dams. Therefore, in order to locate suitable sites, two approaches were followed. The first was the Boolean approach using topographical, geological and landcover data in a geographic information system (GIS) environment for a previously glaciated terrain near Stockholm. The results of the Boolean approach were complemented by a groundwater balance model and a topographic wetness index (TWI). The second approach involved spatial multi-criteria analysis (SMCA) applied to a region with different geological and hydrological conditions. SMCA was applied in Northern Pakistan using factors such as topography, geology, landcover, soil thickness and TWI. Two weighting techniques, the analytic hierarchy process (AHP) and the factor interaction method (FIM), were employed and compared. The Factor removal technique was employed to assess the sensitivity of the model for each factor. Aquifer thickness is an important factor while planning subsurface dams and data regarding the soil thickness is often not available at larger scale. Therefore a simplified regolith model (SRM) was developed for estimating the regolith thickness in previously glaciated terrain with a high frequency of rock outcrops, based on a digital elevation model (DEM) and an optimized outcrop search algorithm. In order to analyse the dynamics of the groundwater flow, a transient 3D groundwater flow model was developed for a subsurface dam. Methods applied to locate suitable sites for the construction of subsurface dams showed some promising results and need to be applied and tested in areas with different hydrological and geological conditions. The Boolean approach is a simple method that could be used during early planning stages for locating suitable sites for the construction of subsurface dams. The SMCA framework enabled the integration of knowledge for decision making, where the weights had a more significant influence on the results than the choice of the weighting method. AHP was considered to be the more robust model for assigning weights in this study. The factor removal technique showed that the modeling results were least sensitive to soil depth and most sensitive to land cover for the construction of subsurface dams. SRM showed reasonable results and could be used in engineering projects prior to detailed field investigations in formally glaciated terrain when borehole data is not available. The groundwater flow modelling results helped to develop some sustainable pumping scenarios to demonstrate the benefits of the subsurface dam. Groundwater flow model results also facilitated the selection of a suitable site for placing a subsurface dam in order to maximize the groundwater storage upstream. It was concluded in this project that the subsurface dams could sustainably be used to mitigate the water supply issues in formerly glaciated humid terrain such as in Sweden and dry climatic areas such as in Pakistan. Moreover, subsurface dams can play an important role in water resources management in coastal areas of formerly glaciated terrain, where saltwater intrusion is a rising environmental issue. Also in dry climatic areas like in Pakistan, methods such as SMCA could make the planning step more robust before the actual construction of dams. Themethods and findings presented in this thesis can be considered to be one tentative step of scientific contribution for better analysis, assessment and the location of subsurface dams.QC 20160210
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Bart, Gwendolyn Diane. "Lunar Surface Geology From Analysis of Impact Craters and Their Ejecta." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/193987.
Full textAbstract:
Analysis of impact craters and their ejecta addresses someunanswered questions about the lunar surface. First I estimatethe regolith depth on the south farside of the Moon to be about40 m, which is significantly deeper than the nearside regolith,estimated to be 3-16 m. This result is obtained by studyinghundred meter diameter flat floored craters, using the method ofQuaide and Oberbeck (J. Geophys. Res., 1968, 73, 5247-5270). This measurement has implications for the formation of the lunarregolith, and for interpretation of samples returned in thefuture by astronauts or automated sample return missions.Next, I report the discovery of a method that distinguishesbetween primary and distant secondary craters in high resolutionplanetary images. For a given crater size, the largest bouldersof secondary craters are significantly larger than those ofprimary craters. The ability to identify distant secondarycraters will help constrain primary production rates of smallcraters and improve surface age determination of small areasbased on small crater counts.Third, I characterize the distributions of boulders ejected from18 lunar impact craters. I find that in large craters, thelargest boulders are preferentially ejected at low velocities(closer to the crater), whereas the largest boulders from smallcraters are ejected over a wider range of ejection velocities. Also, for a given crater size, deeper regolith reduces themaximum ejection velocity attained by a boulder ejected from acrater. I show that this is a logical result of the streamlinesof excavation in an impact when there are no coherent boulders inthe regolith. Cumulative plots of the boulders have slopessteeper than -2, as do secondary craters. This result isexpected because ejecta fragments produce secondary craters.Finally, I describe the morphology of some lunar crater walllandslides that strongly resemble martian gullies, despite thelack of geologically active water on the Moon today or in thepast. The lunar features indicate that alcove-channel-apronmorphology, attributed on Mars to seepage of liquid water, canalso form via a dry landslide mechanism. Therefore alcove-channel-apron morphology is not diagnostic of water carvedgullies.
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Spry, Melissa J., and n/a. "The Regolith and landscape evolution of a low relief landscape: Cobar, Central New South Wales, Australia." University of Canberra. Resource, Environmental & Heritage Management, 2003. http://erl.canberra.edu.au./public/adt-AUC20050704.162445.
Full textAbstract:
Construction of a 1:250,000 scale regolith-landform map of the Cobar area of central New
South Wales (NSW) Australia, demonstrates the presence of a wide range of previously undescribed
regolith materials, landforms and landscape features in the region. The map covers the east-west extent
of the Cobar Basin, extends to the west onto the Darling River Floodplain, and east onto rocks of the
Girilambone Group. The mapping area is centred on the Cobar township and covers -14,730 krn2
between 303113 and 446113 E and 6483184 and 6586183 N (AGO 66, MGA Zone 55). 48 regolithlandform
units have been identified, including both transported (alluvial, colluvial, aeolian, lacustrine)
and in situ materials. A range of siliceous, ferruginous and calcareous indurated materials are also
present.
Four major drainage types have been identified based on lithological, sedimentological and
topographic differences in alluvial materials. The 4 drainage types include: 1) modern drainage; 2)
maghemite and quartzose gravels elevated 1-2 m relative to the modern drainage; 3) higher
topographically inverted, and at least partly silicified, gravels; and, 4) sediments of Cretaceous origin.
Multiple phases of drainage stability and instability from the Cretaceous to the present are indicated
within the sediments. Breaching of drainage divides and increased dissection of the modern drainage,
especially to the south of Cobar, indicate possible tectonic movement across a major regolith-landform
boundary in the southern map area. Colluvial materials are more widespread to the north of Cobar
reflecting the increased landscape dissection to the south. Colluvial fans are preserved adjacent to
major rangefronts. Aeolian and lacustrine materials include longitudinal dunefields of the Darling
River floodplain, source bordering dunes, and small lunettes associated with the Barnato Lakes system.
Regolith-landform mapping at Cobar has been used to assess the applicability of previously
developed landscape evolution models of the Cobar Block and surrounding region, and to develop a
new landscape evolution model for the region. The new landscape evolution model of Cobar indicates
minimal deposition of Cretaceous sediments, succeeded by high-energy early Tertiary fluvial regimes
across the Cobar landscape. Weathering and sediment deposition continued into the Miocene, coupled
with deep valley incision on the Cobar Block associated with early Oligocene regression. By the close
of the Miocene, the Cobar Block had eroded to predominantly bedrock terrain and widespread filling of
previously incised valleys occurred. A decrease in erosion and fluvial activity led to the formation of
the modern drainage during the Pliocene-early Quaternary, followed by the formation of alluvial,
aeolian and lacustrine deposits in the later Quaternary. Regionally, Eromanga Basin sediments were not
extensive over the Cobar Block, and low rates of erosion are recorded at Cobar from the Cretaceous to
the present. Former northerly drainage did exist in this area in the Cretaceous, but was limited in
distribution. By at least the Early Tertiary the Cobar area was a structural high and drainage systems of
the region had assumed their current configuration. These findings do not support interpretations of
AFTT data of significant cover and subsequent stripping over the Cobar Block in the Early Tertiary.
Evidence of landscape evolution from the Cretaceous to the present suggests that the Cobar
landscape has been responding to changes in the primary landscape forming factors of lithology,
climate and to a lesser degree, tectonics. Variations in the these three primary landscape forming
factors have contributed to ongoing weathering, relatively continuous deposition, and periods of
relative stability and instability, particularly in response to climatic and baselevel fluctuations, within a
dynamically evolving landscape throughout the entire Tertiary. Former landscape evolution models of
peneplanation and pediplanation, based on correlation of palaeosurfaces including duricrusts, a deep
weathering profile developed during extended planation in the Early Tertiary, and tectonism during the
late Tertiary in the Cobar area, are not supported by evidence preserved in regolith-landform features at
Cobar.
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Chodas, Mark A. "Improving the design process of the REgolith X-ray Imaging Spectrometer with model-based systems engineering." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93796.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 85-87).
Traditional systems engineering processes have supported the development of many complex and successful space systems. However, some systems experience significant cost and schedule overruns. Systems engineering capabilities need to be improved to manage the expected increase in complexity of future systems. Model-based systems engineering (MBSE) is a new systems engineering paradigm where system models instead of documents are used to track requirements, describe design, support trade studies and analyses, and track verification and validation activities. The system models can be studied to expose relationships and details that are impossible to find when information is scattered across many documents and analytical models. This thesis quantifies the advantages of MBSE over traditional systems engineering by comparing the historical development of the REgolith Imaging X-ray Spectrometer (REXIS), a student-built instrument on the OSIRIS-REx asteroid sample return mission, against a hypothetical development timeline that incorporates information from system models. The system models, constructed in SysML, capture the topological information about the system including the interfaces between all parts of the system, the uncertainty associated with each interface, and the path along which the consequences of selected design choices or requirements flow. The latter two types of information are captured with custom extensions to SysML. The models also provide useful statistics about the development process. The REXIS part count increased 104% between SRR and SDR and 163% between SDR and PDR while the interface count increased 93% between SRR and SDR and 174% between SDR and PDR. Evidence from REXIS shows that incorporating information from system models reduces design iteration and makes the design process more efficient.
by Mark A. Chodas.
S.M.
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Murry, Maisha M. "Dissolution and Sequential Extraction of select radioactive and stable elements in soil and lunar regolith simulants." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1583999571140163.
Full text
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Meurisse, Alexandre René Jacques [Verfasser], Guillermo Akademischer Betreuer] Requena, Jochen M. [Akademischer Betreuer] [Schneider, and Matthias [Akademischer Betreuer] Sperl. "Solar 3D printing of Lunar Regolith / Alexandre René Jacques Meurisse ; Guillermo Requena, Jochen Michael Schneider, Matthias Sperl." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1180392019/34.
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Bah, Boubacar. "Regolith mapping and gold geochemical anomalies in the Siguiri Gold Mine of AngloGold Ashanti, Guinea, West Africa." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1019878.
Full textAbstract:
Gold exploration in the laterite terrains of the Siguiri basin (Guinea-West Africa) is discussed in this thesis. It seeks to propose and develop effective and reliable geochemical exploration techniques applied in such laterite terrains. The study is also intended to investigate and provide some geological clues as to why, in some target areas, the reconnaissance test drilling across the geochemical anomalies couldn’t intersect economic gold mineralisation. Targets were generated based on soil geochemical results, some of which were drilled without delivering economic discoveries even on areas with strong and consistent geochemical signatures. To find the failure and define the appropriate methods to be used is the core of the thesis. More importantly, the geological observation is aimed at sourcing and establishing the nature and validity of geochemical anomalies within the license area and their relationship with the underlying lithologies and structural networks. The geological field work conducted during this study is mostly based on regolith and surface geological mapping. The thick laterite cover, deep weathering, bedrock geology, gold geochemistry (the gold geochemical anomalous results are defined according to historical data before 2007), soil formations and variations in climate conditions are emphasized to illustrate the importance of mineral element mobility and dispersion in the weathering profiles. The knowledge and experience in regolith geochemistry and regolith mapping provide the advantage to exploration geologists. The depletion of ore resources and reserves in Siguiri and the continuous decline of the gold price in comparison to the complexity of exploring for gold are demanding more scientific-related thoughts and techniques to be integrated in the available geological, geochemical and geophysical information so as to reduce costs. The integration of good exploration strategy and technique may result in the possibility of making viable discoveries in this highly competitive geological environment where the mineral resources become depleted every day.
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Russow, Frank. "Struktur, Eigenschaften und Gefährdungspotentiale des oberflächennahen Untergrunds in historischen Erzbergbaugebieten des zentraleuropäischen Mittelgebirgsraums." Doctoral thesis, Universitätsbibliothek Leipzig, 2005. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-34052.
Full textAbstract:
Thema der vorliegenden Arbeit ist die Identifikation, Differenzierung und Bewertung von vorhandenen Schwermetallreservoirs im Hangbereich historischer Erzbergbaugebiete im Nordpfälzer Bergland und dem Spessart. Dazu wurden auf Grundlage von 115 Bodenprofilen entlang von 14 Hangsequenzen die holozäne Umweltgeschichte, die Verbreitung und Struktur sowie ausgewählte ökologische Eigenschaften der quartären Hangsedimente erstmalig integrativ analysiert. Besondere Beachtung fanden hierbei die Schwermetallgehalte der quartären Hangsedimente und ihr immanentes Gefährdungspotential, das für die Untersuchungsgebiete zum ersten mal auf Grundlage der aktuellen rechtlichen Grundlagen bestimmt wurde. Die Auflösung einer hochauflösenden Boden- und Sedimentaufnahme mit exemplarischer Beprobung ermöglichte die Analyse vieler Details, Merkmale und Eigenschaften der Sedimente und Bodenbildungen dieser (stark) gestörten Standorte im Mittelgebirgsbereich.
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Baloochestani, Farshad. "Estimation of Hydraulic Properties of the Shallow Aquifer System for Selected Basins in the Blue Ridge and the Piedmont Physiographic Provinces of the Southeastern U.S. Using Streamflow Recession and Baseflow Data." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/geosciences_diss/2.
Full textAbstract:
The objectives of this research are to measure the aquifer properties (S, T, and K) of selected watersheds delineated to the U.S. Geological Survey gauging stations using streamflow recession and baseflow data and to describe the relations among the properties of shallow aquifers and the physical properties of the basins, such as slope, regolith type and thickness, and land use type. Geographic Information System (GIS) techniques are utilized to investigate critical physiographic controls on transmissivity and storage coefficients on a regional basis. Moreover, the effect of evapotranspiration on recession index is illustrated. Finally, a detailed quantitative comparison of results for the Piedmont and the Blue Ridge Physiographic Provinces in southeast of the U.S. is provided. Recession index, annual groundwater recharge, and annual baseflow data were obtained from 44 USGS-gauging stations with drainage areas larger than 2 (mi2) and less than 400 (mi2). These gauging stations are located in Georgia and North Carolina. Analyses of data focused on GIS techniques to estimate watershed parameters such as total stream length, drainage density, groundwater slope, and aquifer half-width. The hydraulic diffusivity, transmissivity, and storage coefficient of watersheds were computed using hydrograph techniques and the Olmsted and Hely, and Rorabaugh mathematical models. Median recession index values for the Blue Ridge and Piedmont Provinces are 87.8 and 74.5 (d/log cycle), respectively. Median areal diffusivity values for the Blue Ridge and Piedmont are 35,000 and 44,200 (ft2/d), respectively. Median basin-specific estimates of transmissivity for basins in the Blue Ridge and Piedmont are 150 and 410 (ft2/d), respectively. The large values of transmissivity obtained for the Piedmont regolith may be attributed to the thick regolith, low values of basin relief, and voids that develop as a result of fracturing, foliation, weathering, and fractured quartz veins in the saprolite. Median basin-specific estimates of storage coefficient for basins in the Blue Ridge and Piedmont are 0.005 and 0.009, respectively. In general, the results from this study reveal great differences in basin-specific hydraulic parameters of the regolith material within the Piedmont compared to that of the Blue Ridge Physiographic Province.
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Mahizhnan, Annamalai. "Red-brown hardpan: distribution, origin and exploration implications for gold in the Yilgarn Craton of Western Australia." Thesis, Curtin University, 2004. http://hdl.handle.net/20.500.11937/1732.
Full textAbstract:
Red-brown hardpan occurs extensively in Western Australia in the arid and semi-arid regions of the Murchison, Pilbara and Eastern Goldfields divisions, between longitudes 115ºE and 124ºE and latitudes 23ºs and 30ºs. It occupies an area of about 360,000 sq. km, two thirds of which occurs in the Yilgarn Craton. The purpose of this research is to map the distribution of red-brown hardpan in the Yilgarn Craton of Western Australia; study the relationship between landscape, soil texture and vegetation; investigate the physical characteristics, petrology, mineralogy, geochemistry and cementing agents; and thereby determine the processes invaded in forming red-brown hardpan. The relation of red-brown hardpan to gold is investigated and determined its implications in mineral exploration. The main case study areas were the Goldfields Gas Pipe Line, the Federal Open Pit Gold mines and the Menzies district in the Kalgoorlie-Menzies region of the Eastern Goldfields; areas in and around the Woolgorong Station in the Murchison Province and at the Wiluna Gold Mines in the Northeastern Goldfields. The findings and conclusions of this research are summarised below. Red-brown hardpan occurs at or near the land surface and may vary from less than one metre to more than 10 m thick. It is exclusively developed in colluvium and alluvium, showing varying stages of cementation ranging from weakly cemented through moderate to strongly cemented. In addition, calcrete and red-brown hardpan occurs together in many places, south of the Menzies line, and this distribution suggests that red-brown hardpan was once more extensive and has been subsequently replaced by carbonate to form calcareous red-brown hardpan and calcrete. Red- brown hardpan predominantly occurs in regions with Q50 mm annual rainfall.In present-day higher rainfall (400 to 500 mm) regions, red-brown hardpan is being weathered. There is no relationship between the distribution of mulga (Acacia aneura) and red-brown hardpan. Red-brown hardpan is exclusively developed in colluvium containing a minimum of 20% quartz, 15% clays and 2% iron oxides. It is bright reddish brown to reddish brown, earthy, with a sandy loam texture, blocky structure and porous. Red-brown hardpan is hard (up to 12 MPa), being characterised by sub-horizontal laminations predominantly of uncemented kaolinite. Ped surfaces may be coated by Mn oxide and carbonate which may be precipitated along the laminations. The mineralogy of the cement is complex. Data from XRD, SEM, TEM, EFTEM, FTIR and NIR investigations show poorly-ordered kaolinite and opal-A as the main components. Illuvial multilayered argillaceous cutans containing silica and alumina in a ratio of 2:l form the cement. Secondary silica (SiO2-95%) coatings are common, mainly as opal-A, on ped surfaces and on the inner walls of voids and vughs. Etch pits are developed in these coatings and some of them are filled by kaolinitic clays. Selective dissolution experiments using acid ammonium oxalate show that oxalate- soluble amorphous and poorly ordered silica and alumina in red-brown hardpan have molar ratios of about 1.6 to 2 A1203:SiO2.These results suggest that red-brown hardpans were formed where there was sufficient water during the wet season to dissolve alumina and silica, but insufficient to leach them. During the subsequent dry season, the dissolved alumina and silica was precipitated as poorly-ordered kaolinite and opal-A. Successive dissolution and precipitation led to fusion of poorly-ordered kaolinite and opal-A at a nanometre scale to progressively cement the colluvium. The age of the red-brown hardpans, estimated by paleomagnetic dating of hematite, is from Pleistocene to present. Based on the findings of this research, the red-brown hardpan is redefined and primarily classified on its degree of cementation as: (1) weakly cemented, (2) moderately cemented and (3) strongly cemented. It is further classified chemically into: (1) siliceous, (2) calcareous and (3) ferruginous. In the Yilgarn Craton, red-brown hardpan is believed to occur mainly north of the 'Menzies Line'. However, this study reveals the presence of red-brown hardpan 75- 150 km south of the Menzies Line and the new southern boundary is closer to latitude 29ºs. Geochemical investigation at the Federal Open Pit Gold mines, Broad Arrow, north of Kalgoorlie indicate that there are Au anomalies in red-brown hardpan. Gold concentration is up to 50 ppb against the background anomaly of 10 ppb. Sequential and partial extraction analyses show significant correlation of Au with Ag, Ca, Ce, Co, Mg, Mn and Ni. This suggests that the Au concentration in red-brown hardpan is due to: (a) mechanical dispersion due to reworking of Au-bearing clasts in the sediment and (b) hydromorphic dispersion from the underlying mineralisation. It can therefore be used as a useful sampling medium for gold exploration.
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Robinson, Danielle D. Sandvol Eric Alan. "Seismic anisotropy beneath the southern Puna Plateau." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/5362.
Full textAbstract:
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on December 30, 2009). Thesis advisor: Dr. Eric Sandvol. Includes bibliographical references.
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Obregon, Laura. "Generating And Measuring Prescribed Levels Of Cohesion In Soil Simulants In Support Of Extraterrestrial Terramechanics Research." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/832.
Full textAbstract:
Scientists have been well aware of the complexity of Martian and lunar regoliths. There are vast unexplored areas on both, the Moon and Mars, as well as uncertainties in our understanding of the physicochemical properties of their regoliths. Lunar and Martian regoliths differ from terrestrial soils in that they appear granular, but are expected to contain some cohesion. As such, cohesion in regolith poses challenges for future space operations, more specifically for landing, settlement, and mobility purposes. The ability to induce prescribed levels of cohesion in regolith simulants and reliably measure it would allow scientists to evaluate space technology limitations under different operational scenarios on Earth prior to a mission. Therefore, the objectives of this research were to (1) develop methods to induce prescribed levels of cohesion in dry granular media, and (2) evaluate accessible and reliable testing methods to measure cohesion.
We developed and evaluated several methods to induce cohesion in two types of dry sand, F-75 silica sand and generic play sand. The methods to induce cohesion included play sand mixed with sugar-water, polymeric sand, and nanocellulose fibers, as well as F-75 sand mixed with polydimethylsiloxane, polyvinyl acetate, crystalline silica, agar, zero-valent iron, adhesive spray, and sand surface modification using a plasma gun. Each method was assessed for advantages and disadvantages, and laboratory specimens produced using the most promising methods were tested at different compositions and densities to measure cohesion. The laboratory methods used to measure the cohesion included direct shear test, simple direct shear test, and vertical cut test. The results from these tests were then compared to tensile strength tests, using a split box test. In addition, these tests were also performed on lunar simulants JSC-1A and GRC-3 at different densities. The direct shear apparatus was available, but the other three devices were fabricated as part of this work. Based on the research results, simple methods to potentially induce low levels of cohesion in dry granular media are suggested along with suitability of laboratory methods to measure the added cohesion.
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Guerin, Kristy L. "Wildfire as an agent of geochemical and mineralogical differentiation at the earth's surface." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/230844/1/Kristy_Guerin_Thesis.pdf.
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This research investigates the impact of fires on mineralogical assemblages and geochemical fluxes at the Earth’s surface. The research shows that the high temperatures that affect soil during fires leads to the formation of pyrogenic minerals such as metakaolin. Pyrogenic minerals can be metastable, breaking down upon weathering resulting in geochemical fractionation. This project contributes to our current understanding of fire as a major driver of geochemical cycling in the surficial environment.
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Murphy, Daniel M. K. "Regolith expression of hydrothermal alteration : a study of the Groundrush and Vera Nancy gold deposits of Northern Australia." University of Western Australia. School of Earth and Environment, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0186.
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[Truncated abstract] Mineralogical and geochemical characteristics were identified for regolith overlying two Australian Au deposits that discriminate mineralized and associated hydrothermally-altered rock from weathered rock that was not hydrothermally-altered. Mineralization was lithologically controlled within a previously unrecognized diorite dyke at the lower Proterozoic mesozonal Groundrush deposit, Tanami region, Northern Territory. Although hydrothermal alteration effects within the dyke were subtle and obliterated by weathering, Ti/Zr ratios clearly discriminated the diorite dyke from visually indistinguishable but generally unmineralized dolerite. In contrast, the Carboniferous Vera Nancy low-sulphidation epithermal Au deposit, located in the Drummond Basin, northeast Queensland, comprises structurally-controlled quartz veins within a relatively chemically homogenous suite of andesitic lavas and subvolcanic intrusions. A zoned hydrothermal alteration system in the hangingwall of the main vein grades from a proximal silica-pyrite alteration zone through an argillic zone into regionally extensive propylitic 'background'. Deep chemical weathering has destroyed the minerals diagnostic of the different alteration zones in bedrock to leave a kaolinitic regolith overlying all alteration zones. However, the silica-pyrite alteration zone is identified in regolith by retention of the anomalous concentrations of Au, As, Sb and Mo present in bedrock, and mineralogical characteristics, determined from X-ray diffraction investigations, discriminated weathered argillic from propylitic alteration zones. ... Metasomatic reactions, including weathering reactions, are typically difficult to specify, as some reactants and products may be removed by fluids, and thus evidence for their involvement is absent from the observed assemblages. In addition, the range of possible reactions even for relatively simple systems is such that identifying the real reaction may be intractable without additional information. Linear algebra provides an approach to this problem. If minerals and aqueous phases are represented as columns in a matrix with elements as rows, any vectors in the null space of this matrix (if it is greater than 0-dimensional) provide coefficients to balance reactions between the phases. The 'Gale' vectors for a set of phase are the row vectors of any basis for this null space. The relationships between phases are clarified through examination of these vectors in d-dimensional Gale vector space, where d is the dimension of the null space. The hyperplane normal to any vector in Gale vector space separates the space into reactant and product half-spaces. The geometric relationships between the Gale phase vectors describe all the possible reactions. Because changes to parameters (e.g. volume, mass, density) can be determined for each possible reaction, Gale analysis can be used to identify reactions consistent with these constraints. Gale analysis of weathering at the Vera deposit indicated that all the possible weathering reactions producing kaolinite, goethite and quartz from illite, pyrite and siderite resulted in minor reductions in volume and mass only, whereas acid-neutral weathering of propylitic rocks exhibited greater mass losses, consistent with observation and geochemical interpretation.
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Baker, Andrew K. M. "Metal geochemistry of regolith in the Mount Lofty Ranges and associated alluvial fans of the Adelaide Plains, South Australia /." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09S.B/09s.bb167.pdf.
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Thesis (B. Sc.(Hons.)--University of Adelaide, Dept. of Geology and Geophysics, 2000.Australian National Grid Reference Adelaide sheet SI 54-9 1:250,000. Includes bibliographical references (leaves 73-78).