Journal articles on the topic 'The Rocks'
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Noma, Kensuke, Naotsugu Oyama, and James K. Liao. "Physiological role of ROCKs in the cardiovascular system." American Journal of Physiology-Cell Physiology 290, no. 3 (March 2006): C661—C668. http://dx.doi.org/10.1152/ajpcell.00459.2005.
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Rho-associated kinases (ROCKs), the immediate downstream targets of RhoA, are ubiquitously expressed serine-threonine protein kinases that are involved in diverse cellular functions, including smooth muscle contraction, actin cytoskeleton organization, cell adhesion and motility, and gene expression. Recent studies have shown that ROCKs may play a pivotal role in cardiovascular diseases such as vasospastic angina, ischemic stroke, and heart failure. Indeed, inhibition of ROCKs by statins or other selective inhibitors leads to the upregulation and activation of endothelial nitric oxide synthase (eNOS) and reduction of vascular inflammation and atherosclerosis. Thus inhibition of ROCKs may contribute to some of the cholesterol-independent beneficial effects of statin therapy. Currently, two ROCK isoforms have been identified, ROCK1 and ROCK2. Because ROCK inhibitors are nonselective with respect to ROCK1 and ROCK2 and also, in some cases, may be nonspecific with respect to other ROCK-related kinases such as myristolated alanine-rich C kinase substrate (MARCKS), protein kinase A, and protein kinase C, the precise role of ROCKs in cardiovascular disease remains unknown. However, with the recent development of ROCK1- and ROCK2-knockout mice, further dissection of ROCK signaling pathways is now possible. Herein we review what is known about the physiological role of ROCKs in the cardiovascular system and speculate about how inhibition of ROCKs could provide cardiovascular benefits.
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Zhang, Jin Yu, Huan Sheng Dong, Reza K. Oqani, Tao Lin, Jung Won Kang, and Dong Il Jin. "Distinct roles of ROCK1 and ROCK2 during development of porcine preimplantation embryos." REPRODUCTION 148, no. 1 (July 2014): 99–107. http://dx.doi.org/10.1530/rep-13-0556.
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Cell-to-cell contact mediated by cell adhesion is fundamental to the compaction process that ensures blastocyst quality during embryonic development. In this study, we first showed that Rho-associated coiled-coil protein kinases (ROCK1 and ROCK2) were expressed both in porcine oocytes and IVF preimplantation embryos, playing different roles in oocytes maturation and embryo development. The amount of mRNA encoding ROCK1 and the protein concentration clearly increased between the eight-cell and morula stages, but decreased significantly when blastocysts were formed. Conversely, ROCK2 was more abundant in the blastocyst compared with other embryonic stages. Moreover, immunostaining showed that ROCK1 protein distribution changed as the embryo progressed through cleavage and compaction to the morula stage. Initially, the protein was predominantly associated with the plasma membrane but later became cytoplasmic. By contrast, ROCK2 protein was localized in both the cytoplasm and the spindle rotation region during oocyte meiosis, but in the cytoplasm and nucleus as the embryo developed. In addition, ROCK2 was present in the trophectoderm cells of the blastocyst. Treatment with 15 μM Y27632, a specific inhibitor of ROCKs, completely blocked further development of early four-cell stage embryos. Moreover, we did not detect the expression ofROCK1but did detectROCK2expression in blastocysts. Moreover, lysophosphatidic acid an activator of ROCKs significantly improved the rates of blastocyst formation. These data demonstrate that ROCKs are required for embryo development to the blastocyst stage. Together, our results indicate that ROCK1 and ROCK2 may exert different biological functions during the regulation of compaction and in ensuring development of porcine preimplantation embryos to the blastocyst stage.
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Haga, Raquel B., Ritu Garg, Francesca Collu, Bárbara Borda D'Agua, Sofia T. Menéndez, Audrey Colomba, Franca Fraternali, and Anne J. Ridley. "RhoBTB1 interacts with ROCKs and inhibits invasion." Biochemical Journal 476, no. 17 (September 13, 2019): 2499–514. http://dx.doi.org/10.1042/bcj20190203.
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Abstract RhoBTB1 is an atypical Rho GTPase with two BTB domains in addition to its Rho domain. Although most Rho GTPases regulate actin cytoskeletal dynamics, RhoBTB1 is not known to affect cell shape or motility. We report that RhoBTB1 depletion increases prostate cancer cell invasion and induces elongation in Matrigel, a phenotype similar to that induced by depletion of ROCK1 and ROCK2. We demonstrate that RhoBTB1 associates with ROCK1 and ROCK2 and its association with ROCK1 is via its Rho domain. The Rho domain binds to the coiled-coil region of ROCK1 close to its kinase domain. We identify two amino acids within the Rho domain that alter RhoBTB1 association with ROCK1. RhoBTB1 is a substrate for ROCK1, and mutation of putative phosphorylation sites reduces its association with Cullin3, a scaffold for ubiquitin ligases. We propose that RhoBTB1 suppresses cancer cell invasion through interacting with ROCKs, which in turn regulate its association with Cullin3. Via Cullin3, RhoBTB1 has the potential to affect protein degradation.
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Bayrak, Galyna. "MORPHOLOGIC CLASSIFICATION OF THE BESKIDS ROCKS IN THE UKRAINIAN CARPATHIANS." PROBLEMS OF GEOMORPHOLOGY AND PALEOGEOGRAPHY OF THE UKRANIAN CARPATHIANS AND ADJACENT AREAS, no. 09 (01) (September 25, 2019): 117–32. http://dx.doi.org/10.30970/gpc.2019.1.2806.
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The article deals with morphological classification of the sandstone rocks in the Ukrainian Carpathians Beskids. By the methods of field measurements and mathematical computations the rock peaks heights, their shape, basement lengths and strata thickness have been calculated. The highest rock peaks in the Beskids amounts 32–37 m. The classification from the morphological point of view on the base of rock forms studying has been done. All rocks are divided in two classes: the rocks-outliers and the rocks-outcrops. Among the rocks-outliers 4 types are defined: spire-shaped, chain-shaped, arc-shaped and combined. Spire-shaped rocks are divided into subtypes: tower, spoke and needle. Among the chain-shaped rocks 3 subtypes are defined: wall, bloc and slab. The rocks of combined form are divided into subtypes: 1) with defined form – those of the rocks which are similar to certain objects and 2) undefined forms (cliffs). Among the rocks-outcrops three types are defined: cliff-shaped, canyon-shaped and angular ones. The class of rocks-outliers occurs most often. Among the types the rocks-towers occur most often. They dominate in the rock formations of Urych, Yamelnytsia and Bubnyshche. Many bloc-shaped and plate-shaped rocks are located on the Kliuch Ridge, in Bubnys’ki Rocks, Yamelnytsia. There are rocks-walls of 50–60 m in Urych and Yamelnytsia. The longest rock-wall in Danylov tract near Yamelnytsia has been investigated. Its length is 150 m and height is 17 m. Some needle and spoke rocks are situated in Bubnys’ki Rocks (Odinets’ Rock, Golets’ Rock) and Urych (Hostryi Kamin’ (Sharp Stone) Rock. Unique types are very rare. For instance: Bronenosets’ Rock in Bubnys’ki Rocks (this rock has shape of sail), Sokil (Falcon) Rock in the Kliuch Ridge, mushroom-shaped rock in Yamelnytsia. There is also unique arc-rock in the Kliuch Ridge. In the class of rocks-outcrops the types of cliff and canyon occur equally. The angular-shaped rocks are rarer. The cliff-shaped rocks are situated near Sokolova Mountain, Pozhernytsia Mountain and Kniazhi (Princes) Rocks near Tyshivnytsia. Unique rocks-canyons, the effects of tectonic breaking and gravity-erosion processes, occur on the Kliuch Ridge. The worked out morphological classification of rocks can be used by ascertaining features of rock morphogenesis with education and scientific purposes as well as by assessment of safety level and protection possibilities. Morphological types of the rocks can be considered as valuable objects of geomorphologic heritage and attractions for geo-tourism. Key words: rocks; morphology type of the rock; rock shape; Beskids of Ukrainian Carpathians.
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Zarraq, Ghazi. "Slope Stability Analysis of the Southwestern Limb of Kosret Anticline in Dokan, Northeastern Iraq." Iraqi Geological Journal 54, no. 2A (July 31, 2021): 34–48. http://dx.doi.org/10.46717/igj.54.2a.3ms-2021-07-24.
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The stability of the rock slopes was studied on the southwestern limb of the Kosret Anticline in the Dokan Area in northeastern Iraq to analyze and indicate the danger of rock mass failures along the public street linking Dokan and Quesangaq, Erbil and the road which link between the city and the residential neighborhood of Dokan Lake, as well as the revealing and the analysis of the risk of landslides in the slopes and rocks detectors of exposed rocks of the formations in the study area. The stereographic projection was used in the analysis and classification of the rock slopes. This study has shown that the failures of rocks are fall and day lighting bedding plane. The factors that affect the stability of the slopes were assessed. This research mainly focuses on identifying the types of collapses along the rocky slopes and the factor that affects the instability of the studied slopes. It was found that it is the direction slopes and the interruption geometry. Different treatment methods have been proposed for the studied rock base on the rock slope analysis. The expected failure types that may occur along the road are plane sliding, rock fall, toppling, and probably the failure type in the future may be planner sliding due to the angle of the friction comes to zero degree. The rocky slopes along the road require constant monitoring due to their hazardous conditions. Where it was found that the attitude of the joints and their frequency with the relation between the attitude of the slopes and the rock beds played an important role in the failures, as well as the weak rocks of the Marl layers of the Shiranish, Kometan and Tanjero formations play a key role in responding to weathering and erosion factors that increase the failures of rock slopes.
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Kitchenham, Paul. "Rock Art: “Tatooing” Rocks?" Time and Mind 2, no. 3 (January 2009): 347–48. http://dx.doi.org/10.2752/175169609x12464529903254.
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Xie, Busheng, Lixin Wu, Wenfei Mao, Shengyu Zhou, and Shanjun Liu. "An Open Integrated Rock Spectral Library (RockSL) for a Global Sharing and Matching Service." Minerals 12, no. 2 (January 20, 2022): 118. http://dx.doi.org/10.3390/min12020118.
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Minerals and rocks are important natural resources that are formed over a long period of geological history. Spectroscopy is the basis of the identification and characterisation of rocks and minerals via proximal sensing in the field or remote sensing systems with multi- and hyper-spectral capabilities. However, spectral data is scattered around different institutions worldwide and stored in various formats, resulting in poor data usability and an unnecessary waste of time and information. To improve the usability and performance of mineral spectral data, we developed an integrated open mineral spectral library (Rock Spectral Library, RockSL). Shared spectral data and related information were collected worldwide, and data cleaning measures were performed to retain the qualified spectra and merge all qualified data (raster, vector, and text formats) in a common framework to establish a reliable and comprehensive digital data set for an easy sharing and matching service. A software system was developed for the RockSL to manage, analyse, and apply the spectral data of minerals and rocks. We demonstrate how the information encoded in RockSL can determine the species of unknown rocks and describe specific mineral compositions. We also provide a reference scheme of the work chain and present key technologies for building different spectral libraries in diverse fields using RockSL. New contributions to RockSL are encouraged for this work to be improved to provide a better service and extend the applications of geo-sciences. This article introduces the characteristics of RockSL and demonstrates an experimental application.
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Evgenikou, V., A. Georgopoulos, and M. Korres. "REASSEMBLY OF ROCK SEGMENTS, THE CASE OF AREOPAGUS HILL." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W9 (January 31, 2019): 325–32. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w9-325-2019.
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<p><strong>Abstract.</strong> There are no specifications and/or standards for the restoration of collapsed masses of rocks, as in most cases the rocks bear no historical/archaeological value and their restoration would require significant budget and resources. But plenty of colossal statues, ancient temples, tombs and whole cities are carved on the surface or even expand in the interior of solid natural rocks. These so-called rock-cut monuments are located all around the globe and, in most cases, are made on a grand scale. Earthquakes, rock’s faults, erosion and karst can lead to massive rock collapses.The purpose of this paper is to establish an integrated methodology for the relocation of detached rock segments to their original positions. Specifically, the proposed methodology is based on the case of the Areopagus Hill and involves the generation of 3d models of the rock segments, their virtual reassembly and their utilization for the reconstruction of a part of the peak of the hill.</p>
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Ren, Jia Guo, and Qian Qian Wu. "Discussion on Geological Experiment Technology in Geological Work." Advanced Materials Research 616-618 (December 2012): 60–63. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.60.
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This essay puts silicate rocks test as example on the basic of the analysis of new technology and method of geological experiment. This essay analyses the experimental principal and process of silicate rock’s total iron content, and it based on geology experimental operation process. The essay tries to probe into silicate rock’s mineral chemical composition, rock structure and tectonics through the research of the iron content and other chemical components of silicate rocks. Furthermore, this essay also estimates the optional mineral’s component content of sandstone ore, and then evaluates mining products and industrial and economic value. It is very important to guide the development of the mine.
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Cooper, William E., and Wade C. Sherbrooke. "Choosing between a rock and a hard place: Camouflage in the round-tailed horned lizard Phrynosoma modestum." Current Zoology 58, no. 4 (August 1, 2012): 541–48. http://dx.doi.org/10.1093/czoolo/58.4.543.
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Abstract The round-tailed horned lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats (uniform sand or sand with surface rocks approximately the same size as lizards). An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detection was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P. modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks (masquerade) enhances camouflage attributable to coloration and immobility.
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Grzelak, Katarzyna, and Piotr Kuklinski. "Benthic assemblages associated with rocks in a brackish environment of the southern Baltic Sea." Journal of the Marine Biological Association of the United Kingdom 90, no. 1 (January 14, 2010): 115–24. http://dx.doi.org/10.1017/s0025315409991378.
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Sandy bottoms, with local patches of rocks, dominate the southern Baltic Sea coast. These rock patches create three-dimensional habitats with additional niches that can support diverse assemblages of organisms. In this study we investigated macrofaunal assemblages associated with the boulder field in the brackish Gulf of Gdansk. Of the 30 recorded taxa three animal species (Mytilus trossulus, Balanus improvisus and Electra crustulenta) together with five species of algae were directly attached to rocks. These engineering organisms provided habitats for a further 22 taxa. Among the fauna directly associated with rocks, barnacles (76%) were the most abundant while among indirectly associated biota, oligochaetes were the dominant group (45%). Rock size and algal biomass explained most variance in macrofaunal structure of the assemblages investigated. There were statistical differences in assemblage structure between two separate localities within the rocky patch, despite environmental homogeneity (salinity, water temperature and structure of sea bottom). These differences in assemblage structure were mostly due to differences in dominance of particular species rather than in species composition. Our results show that rocky patches in an otherwise soft sediment habitat provide additional living space for macrofauna leading to an increase in local biodiversity and organismal abundance.
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Cruden, D. M., and T. M. Eaton. "Reconnaissance of rockslide hazards in Kananaskis Country, Alberta." Canadian Geotechnical Journal 24, no. 3 (August 1, 1987): 414–29. http://dx.doi.org/10.1139/t87-052.
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Kananaskis Country is situated in the Front Ranges of the Canadian Rockies in southwestern Alberta. Sedimentary rock thrust northeastwards forms mountain ridges that trend northwest–southeast parallel to the major thrust faults. Older, Palaeozoic rocks—mainly limestone and dolomite—form the ridges and peaks. Younger, Mesozoic rocks—sandstones, quartzites, siltstones, shales, conglomerates, and coals—are more easily eroded and form mountain passes and valleys.A reconnaissance mapped 228 rockslides, 8 km2 of rockslide debris and 96 km2 of talus. The largest rockslide exceeds 50 × 106 m3. Rockslides are most probable in the Devonian Palliser Formation, then in the Permo-Pennsylvanian Rocky Mountain Group, Mississippian Rundle Group, Devonian Fairholme Group, Mississippian Banff Formation, and the younger detrital rocks. Rockslides are most probable on dip and overdip slopes, followed by reverse-dip slopes, oblique and strike-dip slopes, and underdip slopes. Large rock masses have not slid on slopes below their basic friction angle, [Formula: see text]The reconnaissance shows that certain facilities in valleys below steep mountain slopes are exposed to rockslide hazards, and provides a guide for the location of new facilities. Analyses of two mountain slopes show that there are large, hypothetical hazards in Kananaskis. Rockslides are likely and could be destructive. Key words: Front Ranges, Rocky Mountains, Alberta, rockslides, hazards.
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Priya, Rashmi, Xuan Liang, Jessica L. Teo, Kinga Duszyc, Alpha S. Yap, and Guillermo A. Gomez. "ROCK1 but not ROCK2 contributes to RhoA signaling and NMIIA-mediated contractility at the epithelial zonula adherens." Molecular Biology of the Cell 28, no. 1 (January 2017): 12–20. http://dx.doi.org/10.1091/mbc.e16-04-0262.
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Rho kinases (ROCK1 and ROCK2) function downstream of the small GTPase RhoA to drive actomyosin cytoskeletal remodeling. It has often been believed that ROCK1 and ROCK2 may be functionally redundant, as they share a highly conserved kinase domain. However, in this study, we report differential functional effects for these ROCKs at the epithelial zonula adherens (ZA). Using specific siRNA, we found that ROCK1 depletion disrupted cadherin organization at the ZA, accompanied by loss of F-actin and NMIIA, whereas ROCK2 knockdown had no significant effect. Further, ROCK1, but not ROCK2, was necessary to stabilize GTP-RhoA at the ZA, thereby sustaining junctional tension and inhibiting intraepithelial cell movement. We also found that nonmuscle myosin IIA is a major determinant of ROCK1 cortical stability. Thus, despite sharing the catalytic domain with ROCK2, ROCK1 appears to be the dominant kinase essential for junctional integrity and contractile tension at epithelial ZA.
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Pujar, Anant G., A. Sreenivasa, and Ajaykumar N. Asode. "Petrography and Provenance Study of South-Central Part of Kaladgi Basin, Belgaum, Karnataka, India." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 108–12. http://dx.doi.org/10.46660/ijeeg.vol11.iss1.2020.421.
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The area under investigation covers the south-central part of Kaladgi series comprising of sedimentary rocks, mainly quartzarenites. From the geological point of view the study area comprises southcentral part of Kaladgi basin covering around 54 km2 which encompasses rocky hills of moderate height, showing three types of facies i.e., argillaceous, arenaceous and rudaceous. Among these three, arenaceous facies is more prominent in the area. These sedimentary rocks rest unconformably over gneisses. Detailed study of the rocks exposed are done by studying the petrological aspects of the rock samples which were subjected to microscopic studies, bifurcating different minerals and counting each parameter of the minerals which is plotted in the QFR ternary diagram and further illustrating the tectonic provenance of the area. Present work mainly focuses on the studies related to petrological, diagenesis and provenance of the study area where the rocks exposed in the vicinity are quartz arenites indicating that these sediments were deposited in a riverine condition.
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Pujar, Anant G., A. Sreenivasa, and Ajaykumar N. Asode. "Petrography and Provenance Study of South-Central Part of Kaladgi Basin, Belgaum, Karnataka, India." International Journal of Economic and Environmental Geology 11, no. 1 (July 7, 2020): 108–12. http://dx.doi.org/10.46660/ojs.v11i1.421.
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The area under investigation covers the south-central part of Kaladgi series comprising of sedimentary rocks, mainly quartzarenites. From the geological point of view the study area comprises southcentral part of Kaladgi basin covering around 54 km2 which encompasses rocky hills of moderate height, showing three types of facies i.e., argillaceous, arenaceous and rudaceous. Among these three, arenaceous facies is more prominent in the area. These sedimentary rocks rest unconformably over gneisses. Detailed study of the rocks exposed are done by studying the petrological aspects of the rock samples which were subjected to microscopic studies, bifurcating different minerals and counting each parameter of the minerals which is plotted in the QFR ternary diagram and further illustrating the tectonic provenance of the area. Present work mainly focuses on the studies related to petrological, diagenesis and provenance of the study area where the rocks exposed in the vicinity are quartz arenites indicating that these sediments were deposited in a riverine condition.
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Dimitrov, Ivan. "Structural geological methods in the geotechnical practice – rock mass rating. Advantages and problems of the rating methods." Review of the Bulgarian Geological Society 81, no. 1 (2020): 35–54. http://dx.doi.org/10.52215/rev.bgs.2020.81.1.3.
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This paper presents a review of the most common geotechnical rock rating methods. The directional properties of the rock’s anisotropies are exemplified, by a case of resolution of stresses in folded and foliated metamorphic rocks. In such rocks, depending on the geometry of the folds, the ambient stress field can generate varying shear potential along the foliation planes in different parts of the excavation. The commonly used rating schemes, with accent on the geological feasibility of the classifications, are discussed – Protodiakonov’s rock scale, Terzaghi’s grading for construction of tunnels, then the rock quality designation of Deere, the Bieniawski’s rock mass rating (RMR), the Hoek, and Brown’s GSI and the Barton’s Q-system. It is emphasized that in spite of its broad use, the RQD is distorting the statistical weight of the joint groups as some steeply dipping joints may be completely neglected. It is recognized that the RMR is the simplest to use but underestimates the directional properties of the rock anisotropies, which require better definition and has no provision for lithologically varying rock packages, although it has the advantage of using the uniaxial compressive strength, which other systems do not employ. The Hoek and Brown’s criterion went too far with complex empirical relationships, which rely on extensive laboratory testing, so it is no more field criterion. Besides, its geological descriptive powers are rather poor and now, new form of GSI classification is offered for nearly every lithological type. Barton’s Q-system, being best suited to case studies of actual underground constructions, suffers from the fact that is centered nearly exclusively on joints, which may be justified in Norway, where mainly magmatic and high grade metamorphic rocks are present but should be applied cautiously in areas, where sedimentary, volcanic and strongly foliated rocks are exposed. In general, for all the discussed geomechanical classification systems (RMR, GSI, Q) the rule is valid, that they work better in an isotropic, strong but jointed rock masses and do not work well in week layered and foliated rocks.
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Dias, Gilmar Pauli, and Emílio Velloso Barroso. "Determinação experimental do coeficiente de restituição normal de rochas: aplicação na previsão do alcance de blocos em encostas." Anuário do Instituto de Geociências 29, no. 2 (January 1, 2006): 149–67. http://dx.doi.org/10.11137/2006_2_149-167.
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Among the several parameters involved in rock fall analisys, the restitution coefficient, which is related to the kinetic energy wasted after repeated impacts of a rocky body against the ground, is probably the most important and most difficult to acquire. There is the necessity of in situ tests where blocks of rocks are thrown down on the slopes. However these tests cannot be performed in places where people or urban equipments could be in risk. In this paper an acoustic method is used for the measurement of the normal restitution coefficient of rocks. This method is very well known by physicists but it has not been applied in the geosciences and engineering areas. It consists in the sound recording of successive impacts of a rock sphere against a smooth rocky surface. The gravity acceleration was back calculated from data obtained in order to verify if precision of the method is suitable. A sensibility analysis of the coefficient of restitution was already carried out simulating real rock fall problems.
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Tang, Fujian, Yizheng Chen, Zhaochao Li, Xiuyan Hu, Genda Chen, and Yan Tang. "Characterization and field validation of smart rocks for bridge scour monitoring." Structural Health Monitoring 18, no. 5-6 (January 22, 2019): 1669–85. http://dx.doi.org/10.1177/1475921718824944.
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In this study, two types of smart rocks are proposed, characterized, and validated for bridge scour monitoring, including the arbitrary oriented system smart rock and the automatically pointing to south system smart rock. Effect of the smart rocks on the geomagnetic field is numerically studied, and algorithms to localize the position of the smart rocks are developed. Field validation tests are conducted at an open area in Rolla, MO, USA. Results show that the magnetic intensity decreases in cubic function with a distance away from the smart rock. The algorithm can effectively localize the position of smart rocks during validation tests. The effective monitoring range of the two smart rocks is dependent on the flux (or size) of the magnet used to fabricate the smart rocks, the accuracy of the magnetometer, the direction of smart rocks, as well as the intensity and variation of the ambient magnetic field. Compared with arbitrary oriented system smart rock, less measurement points are needed to localize the automatically pointing to south system smart rock.
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Lee, Dong-Keun, Duk-Ho Chung, Woong-Hyeon Jeon, and Chul-Min Lee. "Analysis of igneous rock classification process by earth science teachers using eye trackers." Korean Association For Learner-Centered Curriculum And Instruction 22, no. 15 (August 15, 2022): 461–77. http://dx.doi.org/10.22251/jlcci.2022.22.15.461.
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Objectives The purpose of this study is to find out the characteristics that earth science teachers show in the process of classifying igneous rocks and the difficulties in classifying igneous rocks.
Methods To this end, the researchers collected gaze data and language data in the process of classifying igneous rocks by using a Eyetracker(Tobii Ⅱ) and a think-aloud method from five high school earth science teachers in Jeollabuk-do. Then, the collected data were analyzed using the gaze analysis program and the semantic network analysis, respectively.
Results First, in the process of classifying igneous rocks, earth science teacher’s gaze fixation duration was long in the order of diorite, andesite, rhyolite, gabbro, basalt, and granite. Second, in the semantic network for the classification of igneous rocks by earth science teachers, the eigenvector centrality of words related to the apparent characteristics of rocks such as “particles” and “rock color” was high. Third, in the process of classifying igneous rocks, earth science teachers found it difficult to determine the range of characteristics that determine each igneous rock, that is, the range of rock colors, particle sizes, stripes, etc. In other words, earth science teachers found it most difficult to distinguish diorite, and granite was the easiest to distinguish. In the process of classifying igneous rocks, they classified igneous rocks mainly based on the size of the particles that make up the rocks and the color shown by the rocks rather than the minerals that make up the rocks. In addition, earth science teachers were unclear about the scope of the criteria for classification of igneous rocks.
Conclusions Earth science teachers need to clearly establish personal standards for the classification of igneous rocks. And personal standard for rock classification can be established through various observation experiences as well as the geological knowledge they perceive. Therefore, earth science teachers should be provided with various types of rocks and typical rocks for extensive observation experiences, such as activities to observe rocks and various types of rocks.
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Shine, Richard, Jonathan K. Webb, Mark Fitzgerald, and Joanna Sumner. "The impact of bush-rock removal on an endangered snake species, Hoplocephalus bungaroides (Serpentes : Elapidae)." Wildlife Research 25, no. 3 (1998): 285. http://dx.doi.org/10.1071/wr97022.
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We examined the impact of habitat degradation (removal of surface rocks) on an endangered snake species (Hoplocephalus bungaroides, Elapidae) at 23 sites in south-eastern Australia, by quantifying the impact of rock removal on (i) the availability of suitable shelter-sites for the snakes and their major prey species (the velvet gecko, Oedura lesueurii), and (ii) the numbers of snakes and geckos. Our survey showed that both the snakes and the geckos prefer rocks lying on other rocks, rather than on soil, and select rocks of particular sizes. The rocks removed by bush-rock collectors overlap considerably in size (diameter and thickness) and substrate (rock on rock) with those used by broad-headed snakes and velvet geckos. Multivariate path analysis suggests that population densities of broad-headed snakes (as measured by capture rates) may be determined primarily by gecko numbers, which in turn depend upon availability of suitable rocks. In some sites, rock numbers were substantially reduced by anthropogenic disturbance. Thus, our survey data suggest that bush-rock removal has contributed to the endangerment of H. bungaroides.
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Korol, Anton. "The influence of the rigidity of mining security structures on the stability of side rocks in the coal-rock massif." Technology audit and production reserves 3, no. 1(59) (June 30, 2021): 19–22. http://dx.doi.org/10.15587/2706-5448.2021.235403.
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The object of research is the processes of controlling the state of side rocks to prevent the collapse of the stratified rock strata in the coal-rock massif containing the workings. The studies carried out made it possible to establish the influence of the rigidity of the guard structures of mine workings on the stability of side rocks in the coal-rock massif. It is proved that as a result of the action of an external compressive load on the supporting lateral rocks, the structure, in the form of a model of bunches made of wooden posts, increases its rigidity until the destruction of the security structure. After that, there is an increase in the convergence of side rocks and their destruction. The change in the stiffness of the crushed rock in the filling massif model, which is used to support the lateral rocks, occurs as a result of the compaction of the original material. This is due to repackaging of crushed rock fractions of different sizes and its additional grinding. As a result of this interaction of the side rocks with the filling massif, the integrity of the roof and soil is ensured and convergence is limited. To assess the stability of side rocks, it is proposed to use a dimensionless stress concentration factor k. This coefficient takes into account the rigidity of the guard structures of the mine workings and the flexural rigidity of the side rocks. It was found that when the values of the coefficient k are close to zero (k→0), there is a loss of stability of the guard structures of mine workings and the destruction of side rocks in the coal-rock massif. The preservation of the integrity of the side rocks and the stability of security structures is ensured at values of k>0.1, which corresponds to the parameters of the pliable supporting structures. Most favorably on the condition of side rocks in the coal-rock massif is influenced by the method of backing up the mined-out space of crushed rock. The use of this method excludes the collapse of side rocks. When solving the problem of stability of mine workings at the stage of making technical decisions, it is necessary to predetermine the issues of rigidity of security structures with deformation characteristics of side rocks.
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Iamrurksiri, Anusorn, Takashi Tsubouchi, and Shigeru Sarata. "Rock Moving Operation Using a Rod-Shaped Manipulator." Journal of Robotics and Mechatronics 25, no. 1 (February 20, 2013): 232–39. http://dx.doi.org/10.20965/jrm.2013.p0232.
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At the working front in a quarry, a hydraulic breaker is used to break large rocks into suitable sizes before they are fed into a rock crusher machine. The purpose of this study is to automate the rock breaking operation using a hydraulic breaker. In rock breaking operations, because the range of motion of hydraulic breakers suitable for breaking rocks is limited, the operator of a hydraulic breaker has to use a chisel, which is located at the top of the hydraulic hammer, to bring large rocks closer before they are broken. In this paper, we describe an approach, using stereo vision, to recognize the positions and shapes of large rocks and the automation of rock moving operations. For rock recognition and rock moving experiments, we set up a scaled down experimental environment in a laboratory and use small rocks and a robotic manipulator in the experiments.
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Zhang, Ying Hua, Bo Chuan Zhao, Zhou Jing Ye, Zhi An Huang, and Ming Shan Gong. "Experiment Research of Luming Molybdenum Mine Rock Physical and Mechanical Properties." Advanced Materials Research 881-883 (January 2014): 1726–31. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1726.
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Physical and mechanical properties of rocks are the fundamental factors affecting the slope stability, the rock physical and mechanical properties of the Luming molybdenum mine were tested and analyzed in the laboratory. The results can provide us the basic data and reference to do numerical simulation and physical simulation of slope stability. The experimental results showed that: the greater the depth of rock of Luming molybdenum mine, the greater the density becomes,so as the freeze-thaw coefficient; the rock strength complies with the general rule; uniaxial tensile strength of dried rocks is much larger than water-saturated rocks; various rocks compressive strength σ3 rose up with σ1 rising; the shear strength of the rocks containing weak structure surface is far less than the shear strength of the intact rocks.
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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips: How Should Rocks Be Labeled?" Rocks & Minerals 63, no. 5 (September 1988): 407. http://dx.doi.org/10.1080/00357529.1988.11761873.
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Titamgim, R. Dirk. "Questions and Answers about Rocks: Rock Chips: Are There Rocks That Bend?" Rocks & Minerals 67, no. 3 (June 1992): 194–98. http://dx.doi.org/10.1080/00357529.1992.9926483.
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He, M. M., F. Pang, H. T. Wang, J. W. Zhu, and Y. S. Chen. "Energy Dissipation-Based Method for Strength Determination of Rock under Uniaxial Compression." Shock and Vibration 2020 (August 13, 2020): 1–13. http://dx.doi.org/10.1155/2020/8865958.
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The energy conversion in rocks has an important significance for evaluation of the stability and safety of rock engineering. In this paper, some uniaxial compression tests for fifteen different rocks were performed. The evolution characteristics of the total energy, elastic energy, and dissipated energy for the fifteen rocks were studied. The dissipation energy coefficient was introduced to study the evolution characteristics of rock. The evolution of the dissipation energy coefficient for different rocks was investigated. The linear interrelations of the dissipation energy coefficients and the yield strength and peak strength were explored. The method was proposed to determine the strength of rock using the dissipation energy coefficients. The results show that the evolution of the dissipation energy coefficient exhibits significant deformation properties of rock. The dissipation energy coefficients linearly increase with the compaction strength, but decrease with the yield strength and peak strength. Moreover, the dissipation energy coefficient can be used to determine the rock burst proneness and crack propagation in rocks.
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Love, Sean D., and Robert C. Bailey. "Community development of epilithic invertebrates in streams: independent and interactive effects of substratum properties." Canadian Journal of Zoology 70, no. 10 (October 1, 1992): 1976–83. http://dx.doi.org/10.1139/z92-268.
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The composition of macroinvertebrate communities living on rocks in streams depends on arrivals at a particular rock, available microhabitats, and biotic interactions among colonizers. We manipulated the color (dark, light), size (82 – 1320 cm2 surface area), and shape (sphere, rectangle, cube) of individual rocks to assess their independent and interactive effects on the development of the epilithic community and the physical displacement (i.e., disturbance) of the particles. Disturbance depended on the size and shape of the rocks. Smaller particles were more disturbed, while rectangular rocks of a given size had more frequent disturbance events than spheres or cubes. Many interactions among the manipulated factors were detected in their effects on taxonomic richness and total invertebrate abundance and density. Although several commonly observed effects were found (e.g., increased richness with greater substratum complexity and size), these patterns depended in many cases on the particular set of shapes and colors examined. Additionally, the site (5 m2) within the experimental area where a rock was located had strong effects on both disturbance and the invertebrate community. The two most common taxa also differed in their relationship with disturbance on different particle shapes: Chironomidae were relatively common on more frequently disturbed rectangular and cubic shapes, while Simulium were more common on the less disturbed spheres. Generalizations about the effects of substratum characteristics (e.g., size, "complexity") should be made with caution. Different features of the rock itself, qualities of the rock's location at a larger spatial scale, seasonal influences, and variation in response among taxa may all influence the development of the epilithic community in an interactive fashion.
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Prémaillon, Mélody, Vincent Regard, Thomas J. B. Dewez, and Yves Auda. "GlobR2C2 (Global Recession Rates of Coastal Cliffs): a global relational database to investigate coastal rocky cliff erosion rate variations." Earth Surface Dynamics 6, no. 3 (August 9, 2018): 651–68. http://dx.doi.org/10.5194/esurf-6-651-2018.
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Abstract. Rocky coast erosion (i.e., cliff retreat) is caused by a complex interaction of various forcings that can be marine, subaerial or due to rock mass properties. From Sunamura's seminal work in 1992, it is known that cliff retreat rates are highly variable over at least four orders of magnitude, from 1 to 10 mm yr−1. While numerous local studies exist and explain erosion processes at specific sites, there is a lack of knowledge at the global scale. In order to quantify and rank the various parameters influencing erosion rates, we compiled existing local studies into a global database called GlobR2C2 (which stands for Global Recession Rates of Coastal Cliffs). This database reports erosion rates from publications, cliff setting and measurement specifications; it is compiled from peer-reviewed articles and national databases. In order to be homogeneous, marine and climatic forcings were recorded from global models and reanalyses. Currently, GlobR2C2 contains 58 publications that represent 1530 studied cliffs and more than 1680 estimated erosion rate. A statistical analysis was conducted on this database to explore the links between erosion rates and forcings at a global scale. Rock resistance, inferred using the criterion of Hoek and Brown (1997), is the strongest signal explaining variation in erosion rate. Median erosion rates are 2.9 cm yr−1 for hard rocks, 10 cm yr−1 for medium rocks and 23 cm yr−1 for weak rocks. Concerning climate, only the number of frost days (number of day per year below 0 ∘C) for weak rocks shows a significant, positive, trend with erosion rate. The other climatic and marine forcings do not show any clear or significant relationship with cliff retreat rate. In this first version, GlobR2C2, with its current encompassing vision, has broad implications. Critical knowledge gaps have come to light and prompt a new coastal rocky shore research agenda. Further study of these questions is paramount if we one day hope to answer questions such as what the coastal rocky shore response to sea-level rise or increased storminess may be.
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Xia, Bin Wei, Ke Hu, Yi Yu Lu, Dan Li, and Zu Yong Zhou. "Model Test Study on Influences of Layered Rock Mass Dip Angle on Stability of Deep-Buried Tunnel." Applied Mechanics and Materials 90-93 (September 2011): 2363–71. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.2363.
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Physical models of layered rock mass with different dip angles are built by physical model test in accordance with the bias failure characteristics of surrounding rocks of layered rock mass in Gonghe Tunnel. Bias failure characteristics of surrounding rocks in thin-layered rock mass and influences of layered rock mass dip angle on stability of tunnel are studied. The research results show that failure characteristics of physical models generally coincide with those of surrounding rocks monitored from the tunnel site. The failure regions of surrounding rock perpendicular to the stratification planes are obviously larger than those parallel to. The stress distributions and failure characteristics in the surrounding rocks are similar to each physical model of different dip angles. The stress distributions and failure regions are all elliptic in shape, in which the major axis is in the direction perpendicular to the stratification planes while the minor axis is parallel to them. As a result, obvious bias failure of surrounding rocks has gradually formed. The physical model tests provide reliable basis for theoretical analysis on the failure mechanism of deep-buried layered rock mass.
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Fernández, F. J., and S. Llana-Fúnez. "Deformación asociada a la falla de Valdoviño (Noroeste del Macizo Ibérico) Deformation related to the Valdoviño fault (Northwest Iberian Massif)." Trabajos de Geología 36, no. 36 (September 12, 2018): 95. http://dx.doi.org/10.17811/tdg.36.2016.95-118.
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Resumen: La sección costera de la falla de Valdoviño expone rocas de falla deformadas en las proximidades de la base de la zona sismogénica de la corteza Ibérica Varisca, en la que estructuras frágiles discretas afectan una zona de deformación predominantemente dúctil. El núcleo de la falla contiene rocas ultramáficas, rocas máficas con granate, anfibolitas, neises cuarzo-feldespáticos y metavulcanitas básicas entre las facies deformadas del granitoide Varisco de A Espenuca. Este artículo describe la deformación y microestructuras relacionadas con la falla desarrolladas en el granitoides. La composición y características tectonometamórficas del resto de rocas presentes en el núcleo de la falla sugieren que las estructuras asociadas a la falla se superpusieron a fábricas tectónicas previas, similares a las que presentan las rocas de los complejos alóctonos del NO del Macizo Ibérico.Palabras clave: microestructura, rocas de falla, corteza continental, EBSD, Orógeno Varisco.Abstract: The coastal section across the Valdoviño fault exposes fault-related rocks deformed at the base of the seismogenic zone of the Iberian Variscan crust. Discrete brittle structures are superimposed over previous predominant ductile deformation fabrics in most rocks. The core of the fault contains ultramafic rocks, garnet-bearing mafic rocks, amphibolites, quartzo-feldspathic gneisses and basic metavulcanites, in between the deformed facies of the A Espenuca Variscan granitoid. We show the deformation and microstructures related to the fault developed in the Variscan granitoid. The composition and tectonometamorphic features of the rest of the related rocks at the core of the fault suggest that deformation structures are superposed onto earlier tectonic fabrics, similar to those present in the rocks of the allochthonous complexes of the NW Iberian Massif.Keywords: microstructure, fault-related rocks, continental crust, SEM-EBSD, Variscan Orogeny.
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Pegu, Ajanta. "Hydrocarbon Source Rock Analysis of Barail & Disang group." International Journal for Research in Applied Science and Engineering Technology 10, no. 5 (May 31, 2022): 2305–12. http://dx.doi.org/10.22214/ijraset.2022.42814.
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Abstract: Petroleum source rocks are those which has sufficient amount of organic matter to generate and expel hydrocarbons to form a commercial accumulation of oil or gas. The objective of this project is to analyze the principal learning on the application of the formation of petroleum source rocks and hydrocarbon generation to exploration activities along with evaluation of petroleum source rocks and hydrocarbon generation. In this project, samples of Barail Group and Disang Group of rocks of Naga-Schuppen Belt were analyzed to determine their source rock characteristics and petroleum generative potentials Keywords: source rock, van Krevelen, Rock Eval pyrolysis, Hydrogen Index, Total organic Carbon content
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Sánchez-Delgado, N., L. Calleja, A. Rodríguez-Rey, A. Setién, and V. G. Ruiz de Argandoña. "Revisión crítica de los ensayos de abrasividad en las rocas y de la influencia de las características petrográficas Critical review of abrasivity tests in rocks and the influence of the petrographic features." Trabajos de Geología 36, no. 36 (September 12, 2018): 347. http://dx.doi.org/10.17811/tdg.36.2016.347-366.
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Resumen: La abrasividad de las rocas tiene gran influencia en algunas de sus aplicaciones, como en los sectores de la piedra natural y en el de ingeniería y obra civil. Para su cuantificación existen más de 15 métodos de ensayo. En este trabajo se hace una revisión de estos métodos clasificándolos en dos grandes grupos: en el caso de la piedra natural se considera el desgaste de los materiales rocosos en contacto con un útil de desgaste, mientras que, en obra civil, por el contrario, se presta atención al desgaste que la roca provoca en los útiles de corte o perforación. Por otra parte, se consideran también aquellos métodos en los que la abrasividad de las rocas se define en función de la variación del valor de alguna de sus propiedades.Palabras clave: Abrasividad, metodos de ensayo, rocas, propiedades fisicas, petrografia.Abstract: The abrasiveness of the rocks has a great influence in some of their applications, such as in the natural stone and in the civil engineering sectors. There are more than 15 test methods for its quantification. This work summarizes these methods and their classification into two large groups: in the case of natural stones the wear of the rock materials when in contact with a wear tool is taken into account; on the other hand, in civil engineering attention is paid to the wear that the rock causes in the cutting or drilling tools. In addition, those methods, in which the abrasiveness of rocks is defined according to the variation of the value of some of its properties, are also considered.Keywords: Abrasivity, testing methods, rocks, physical properties, petrography.
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Ariansyah, Muhammad Resky, Muhammad Fawzy Ismullah Massinai, and Muhammad Altin Massinai. "Rock Types Classification and Distribution on Anabanua Village, Barru Regency, South Sulawesi." Jurnal Geomine 8, no. 1 (June 27, 2020): 1–8. http://dx.doi.org/10.33536/jg.v8i1.530.
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Anabanua Village, Barru Regency is one of the areas in South Sulawesi that has quite unique geological conditions. This condition inseparably comes from the complicated geological process that took place during the formation of the island, Sulawesi. In Anabanua Village, there are many types of rocks such as sedimentary rocks, metamorphic rocks and igneous rocks. This paper aims to map and classify the types of rock by taking samples on different places in the research area. Then we observe the samples physical properties. The results showed, from taking 10 rock samples in different places, they have various characteristics. 8 of them were sedimentary rocks, they are Limestone Quartz, Limestone Sand, Shale, Sandstone, Coal, Limestone Bioturbation, Breccia, and Chert Stone. The other 2 samples were metamorphic rocks, they are Greenschist and Quartzite.
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Ahrari-Roudi, Mohyeddin, and Mojtaba Zaresefat. "Armourstone Quality Analysis for Coastal Construction in Chabahar, Southeast Iran." Water 15, no. 1 (December 30, 2022): 151. http://dx.doi.org/10.3390/w15010151.
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Natural stones (armourstones) of varying sizes and qualities are frequently used to construct breakwaters to protect coastal engineering structures from wave actions for economic reasons. Time-related armourstone deterioration in the form of abrasion and disintegration may result in structural damage. Therefore, it is necessary to investigate the performance and quality of the armourstones, which should be robust and long-lasting. The study aimed to examine the quality of two distinct types of rocks from three breakwaters used as armourstones in the Chabahar region and compare the results to the observed field performance. This study aimed to illustrate why it is crucial to characterise rocks thoroughly before deciding which ones to use in a particular project and to evaluate how well current classification techniques account for the observed field performance of stones that may have complex geological compositions. The physical and mechanical properties of the rock were evaluated through both on-site observation and laboratory testing. The results indicated that the class of rocks used in the breakwater had a wide range of suitability ratings. It was discovered that sedimentary rocks have the best water absorption and porosity properties. In addition, age is a positive factor, as the rate of destruction decreases with age. Component and particle size can also play a role in lithology, which is a significant factor in the rock’s durability. Also, the findings demonstrated that the marine organisms in the rock component play an important role in the stability of these structures, even though rock mass breakwaters are less qualified for breakwater construction as per international coastal engineering standards. According to the findings, a breakwater made of lumachel rock boulders, or alternatively sandstone boulders, will last the longest.
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Muhammad, W. N., N. I. Setiawan, S. Husein, and M. Nukman. "A preliminary study of geology and skarn of Cemorosewu Area, Bayat, Central Java, Indonesia." IOP Conference Series: Earth and Environmental Science 851, no. 1 (October 1, 2021): 012045. http://dx.doi.org/10.1088/1755-1315/851/1/012045.
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Abstract We present the first finding of skarn rocks in Cemorosewu area of East Jiwo Hill, Bayat, Central Java, Indonesia. The geological conditions of this area which related to the appearance of the skarn is also reported. The methods used in this research are DEM acquisition using drone to generate basemap for geological mapping and thin section petrographic analyses. The geological map shows that Cemorosewu area consists of metamorphic rocks (mica phyllite, graphite phyllite, with quartzite and marble lenses), sedimentary rocks (carbonate breccia and siltstone), and igneous rock (microdiorite). Based on the field observation and geological map, the regional metamorphic rocks are the oldest units in this area followed by sedimentary rocks and igneous rock which intruded both rocks. Skarn rocks were cropped out as a boulder along the Kluwihan creek with the maximum size of 8 m in length. The skarn consists of garnet, clinopyroxene, zoisite, actinolite, and minor quartz. Metasiltstone and skarn rock are suggested formed by contact metamorphism of microdiorite intrusion. The marble, which lenses within the phyllites, is suggested to be the protolith of the skarn formation in this area.
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Sengupta, Mita, and Shannon L. Eichmann. "Computing elastic properties of organic-rich source rocks using digital images." Leading Edge 40, no. 9 (September 2021): 662–66. http://dx.doi.org/10.1190/tle40090662.1.
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Digital rocks are 3D image-based representations of pore-scale geometries that reside in virtual laboratories. High-resolution 3D images that capture microstructural details of the real rock are used to build a digital rock. The digital rock, which is a data-driven model, is used to simulate physical processes such as fluid flow, heat flow, electricity, and elastic deformation through basic laws of physics and numerical simulations. Unconventional reservoirs are chemically heterogeneous where the rock matrix is composed of inorganic minerals, and hydrocarbons are held in the pores of thermally matured organic matter, all of which vary spatially at the nanoscale. This nanoscale heterogeneity poses challenges in measuring the petrophysical properties of source rocks and interpreting the data with reference to the changing rock structure. Focused ion beam scanning electron microscopy is a powerful 3D imaging technique used to study source rock structure where significant micro- and nanoscale heterogeneity exists. Compared to conventional rocks, the imaging resolution required to image source rocks is much higher due to the nanoscale pores, while the field of view becomes smaller. Moreover, pore connectivity and resulting permeability are extremely low, making flow property computations much more challenging than in conventional rocks. Elastic properties of source rocks are significantly more anisotropic than those of conventional reservoirs. However, one advantage of unconventional rocks is that the soft organic matter can be captured at the same imaging resolution as the stiff inorganic matrix, making digital elasticity computations feasible. Physical measurement of kerogen elastic properties is difficult because of the tiny sample size. Digital rock physics provides a unique and powerful tool in the elastic characterization of kerogen.
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Astutik, S., and S. L. Nisa. "The Physical Properties of Rocks in Blawan-Ijen Sempol District Bondowoso Regency." Journal of Physics: Conference Series 2392, no. 1 (December 1, 2022): 012029. http://dx.doi.org/10.1088/1742-6596/2392/1/012029.
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Abstract Physical properties are the property of a rock after being tasted without damaging the rock. This research aims to describe the physical properties of rocks in Blawan-Ijen, including rock texture, rock density and rock porosity. The method of collecting data is carried out directly, namely conducting direct research in the field and indirect research by conducting library research. The physical properties of the rocks in Blawan-Ijen have a smooth and rough texture, holocrystalline, light and dark colors, and compact. The density value is relatively high, so it has a fairly high density and resistance. In contrast, the porosity value of the rocks in Blawan-Ijen has three categories: poor porosity, very poor porosity, and high porosity. The texture of the rocks in Blawan-Ijen is smooth, holocrystalline, has small cavities and dark in color.
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Hendrayana, Heru, Hnin Thandar Phyu, I. Gde Budi Indrawan, and Toshitaka Kamai. "Mineralogical, Geochemical, and Mechanical Characteristics of Intrusive Andesite Rock Slope in Sangon 2 Area, Kulon Progo Regency, Indonesia." Journal of Applied Geology 5, no. 1 (August 11, 2020): 25. http://dx.doi.org/10.22146/jag.56345.
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This study was carried out to investigate mineralogical, geochemical, and mechanical characteristics of intrusive igneous rock andesite consisting of Sangon 2 Slope located in Kulon Progo Mountains. Mineralogical characteristics of the rocks consisting of the slope were identified by visual observation of hand specimens in the field and petrographic and X-ray Diffraction (XRD) analyses of the rock samples in the laboratory, which rock genetic classification was determined. Types of rock hydrothermal alterations were determined by the presence of key minerals identified in the petrographic and XRD analyses. Hydrothermal alteration intensity was determined by comparing the number of secondary minerals to the primary minerals observed in the petrographic analyses of thin sections by point counting method. Rock weathering degrees were determined in the field based on the visual characteristics and in the laboratory-based on the Chemical Index of Alteration (CIA) of the rock samples. The rock uniaxial compressive strength (UCS) was determined by point load and compression tests. The results showed that the rocks typically consisted of 6.37 to 74.3% plagioclase, 1.52 to 6.82% quartz, 7.81 to 17.2% hornblende, and 4.81% pyroxene minerals and, therefore, were classified as andesite. The presence of chlorite and calcite as secondary minerals in the andesite rock samples indicated that the parent andesite rocks had undergone prophylactic hydrothermal alteration. Meanwhile, the percentages of primary minerals to secondary minerals indicated that the andesite rocks had undergone weak to high alteration intensity. Based on the visual characteristics, the research area consisted of fresh, slightly, moderately, highly, and completely weathered andesite rocks, and residual soil. The CIA values of the rock samples increased with the increase in rock weathering degree. Rock weathering degrees identified by the visual characteristics appeared to be in good agreement with those classified based on the CIA. The lower part of the mine slope profile consisted of fresh and slightly and moderately weathered andesite rocks, which had relatively high strength and were classified as very strong rocks. Meanwhile, the upper part of the slope profile consisted of highly and completely weathered andesite rocks, which had low compressive strength.Keywords: andesite, hydrothermal alteration, kulon progo, prophylactic alteration, weathering
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Andayany, Helda, and Josephus Ronny Kelibulin. "Characteristics Of Minerals With Spectroskopic IR At The Gold Mining Area Of Botak Mountain." Jurnal Fisika Indonesia 22, no. 2 (April 16, 2020): 7. http://dx.doi.org/10.22146/jfi.v22i2.41529.
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There are three rock samples that have been taken from the gold mining area of Botak mountain. The rock samples were then analyzed with spectroscopic IR to estimate the characteristic of mineral in the area. Analysis results indicate that the type of mineral found in rock samples 2 is dominated by Kaolinite, Organic Carbon, Palygorskite and Quartz. So it can be estimate the type of rock contained in that area is Quartzite. The analysis result of mineral type analysis on rock samples 1 dan 3 have similarities that is Kaolinite, Organic Carbon, Palygorskite, and Albite. So it can be estimate that the other types of rock in the area are Andesite and Limestone. The existence of Andesit and Limestone shows that there has been alteration and hydrothermal mineralization from volcanic origin rock. So it can be estimate that these rocks are the bearing rocks and hosted rocks of base metals and gold. Whereas the quartzite is a bond mineral from gold carrying rocks
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Kozyrev, Anatolii, Eduard Kasparyan, Iuliia Fedotova, and Nikolay Kuznetcov. "The specificities of deformations and failures of highly stressed hard rock massifs." E3S Web of Conferences 129 (2019): 01010. http://dx.doi.org/10.1051/e3sconf/201912901010.
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According to modern concepts, the state of highly stressed hard rock massifs is mostly caused by the effect of gravitational-tectonic stress fields. At that, a probability of brittle rock failure in a dynamic form is very high. Such failures are always accompanied by the significant energy release accumulated during the deformation process. Based on the experimental studies of deformation and failure processes in various types of rock samples from the Kola Peninsula deposits, we have proposed the criteria for classifying rocks as prone to rock bursts. The information for assessing the rock proneness to dynamic failures can be obtained by analysing the strain curve at the pre-peak section when tested on the ordinary presses and testing devices according to the standard methods. If we study the processes of rocks' deformation and energy accumulation under the triaxial loading mode, we can establish the parameters for the occurrence of dynamic failure of rocks. This, in turn, will allow identifying the conditions of such failure in the investigated rocks for a specific mining-engineering situation and, thereby, coming to a scientifically-based prediction of the rocks' proneness to dynamic rock pressure occurrences.
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Kuang, Hong Hai. "Pattern Recognition of Carbonate Rocks in Rs Image." Key Engineering Materials 500 (January 2012): 37–39. http://dx.doi.org/10.4028/www.scientific.net/kem.500.37.
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Pattern recognition of carbonate rocks in RS image have been studied in the paper. Samples of carbonate rocks were scanned into rock images.By analysing these samples of carbonate rocks,a new arithmetic was chosed and a standard curve of carbonate rocks by the arithmetic can be gotten.Rs images were divided into grids.There are curves by the arithmetic in grids. The standard curve of carbonate rocks and curves in grids were compared.If both of curves look very similar,the grid is carbonate rocks area.
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Chouinard, Paul N., and Ken V. Paulson. "A Markov‐Gauss algorithm for blocking well logs." GEOPHYSICS 53, no. 8 (August 1988): 1118–21. http://dx.doi.org/10.1190/1.1442549.
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A characteristic common among petrophysical sections is “blockiness,” which results from the high probability that a given rock and the rocks above and below it are all of the same type. Furthermore, if a new rock type is encountered, the next rock’s type is dependent upon this new type and not on a previous type. This suggests that a Markov chain would be an appropriate basis for modeling such physical parameters as acoustic impedance, electrical resistivity, etc.
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Kaspar, M., C. Latal, M. Blümel, and G. Pittino. "Is soft rock also non-abrasive rock? An evaluation from lab testing campaigns." IOP Conference Series: Earth and Environmental Science 1124, no. 1 (January 1, 2023): 012019. http://dx.doi.org/10.1088/1755-1315/1124/1/012019.
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Abstract Soft rocks are traditionally regarded in terms of low uniaxial compressive strength (UCS <25 MPa). However, other geomechanical and geological properties such as mineralogical composition, and microstructure should be considered when characterizing the properties of soft rocks. The term soft rocks includes a broad variety of rocks coming from various geological origins. Fabric and state of weathering control inherent anisotropic properties of strength and abrasivity of the various rock types. In this study, a suite of rocks from different geologic settings in the Austrian Alps and surrounding countries is analyzed to evaluate connections between the UCS, CERCHAR Abrasivity Index (CAI), and mineralogical composition (equivalent quartz content - FEQu) with emphasis on soft rocks. It is shown, that in order to assess the properties of soft rocks more accurately, the classification scheme can be expanded beyond the simple UCS approach by including mineralogical information and abrasivity values. This holistic approach more adequately captures the breadth of soft rock properties and allows a differentiated distinction of soft rocks in terms of strength and hardness.
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Doyle, Alexandra E., Edward D. Young, Beth Klein, Ben Zuckerman, and Hilke E. Schlichting. "Oxygen fugacities of extrasolar rocks: Evidence for an Earth-like geochemistry of exoplanets." Science 366, no. 6463 (October 17, 2019): 356–59. http://dx.doi.org/10.1126/science.aax3901.
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Oxygen fugacity is a measure of rock oxidation that influences planetary structure and evolution. Most rocky bodies in the Solar System formed at oxygen fugacities approximately five orders of magnitude higher than a hydrogen-rich gas of solar composition. It is unclear whether this oxidation of rocks in the Solar System is typical among other planetary systems. We exploit the elemental abundances observed in six white dwarfs polluted by the accretion of rocky bodies to determine the fraction of oxidized iron in those extrasolar rocky bodies and therefore their oxygen fugacities. The results are consistent with the oxygen fugacities of Earth, Mars, and typical asteroids in the Solar System, suggesting that at least some rocky exoplanets are geophysically and geochemically similar to Earth.
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van der Hoeven, Christopher, Matthew Montgomery, Gregory Sablan, Erich Schneider, and Carlos Torres-Verdín. "Gadolinium tracers for enhancement of Sigma-log contrast measurements." GEOPHYSICS 82, no. 1 (January 1, 2017): EN13—EN24. http://dx.doi.org/10.1190/geo2016-0195.1.
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Borehole neutron measurements are routinely used for in situ rock assessment in hydrocarbon reservoirs. We have used gadolinium oxide nanoparticles for enhancing the sensitivity of macroscopic thermal neutron absorption cross-section (Sigma) measurements of rocks. The gadolinium-based doping agent is used due to its exceptionally high neutron absorption cross section, low cost, and availability; it is also shown to preserve or enhance the differentiation between pore fluids. Injected from a pilot well, the doping agent could thus substantially improve the precision of Sigma-derived saturation measurements. Computational modeling verifies that modest gadolinium concentrations in the rock’s pore volume give rise to significant enhancement of reported Sigma: A concentration of 1750 weight ppm is shown to offer superior contrast enhancement across a wide range of rock solid and fluid compositions. Preliminary experimental work confirms the reported effects obtained with computational modeling of gadolinium doping in simulated porous rocks.
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Leckie, Dale. "Petrology and tectonic significance of Gates Formation (early Cretaceous) sediments in northeast British Columbia." Canadian Journal of Earth Sciences 23, no. 2 (February 1, 1986): 129–41. http://dx.doi.org/10.1139/e86-017.
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Moosebar–Gates sandstones are predominantly litharenites, with some feldspathic litharenites. Both the light- and heavy-mineral suites indicate a mixed source characterized by clastic and carbonate sedimentary rocks, acidic to intermediate plutonic and volcanic igneous rocks, and metamorphic rocks. The sediment sources all fall within a recycled orogenic provenance grouping. Histograms showing stratigraphic variation of mineral content do not indicate any significant progressive unroofing of more deeply buried source rocks.The source area was very extensive regionally and extended well into the Omineca Crystalline Belt and eastern margins of the Intermontane Belt. Zebraic chalcedony was derived from evaporitic rocks of the Charlie Lake Formation, situated east of the Rocky Mountain Trench. Kyanite and almandine garnet were probably derived from the Omineca Crystalline Belt west of the Rocky Mountain Trench. Regional paleoslope dipped towards the north-northwest. Restoration of strike-slip on the Rocky Mountain Trench places potential source areas to the south of the depocentre; this supports paleoslope data. During Moosebar–Gates time the Tenakihi Group in the Omineca Crystalline Belt would have been hundreds of kilometres south of its present location and south of the study area, where it could have provided sediment. Volcanic rocks were derived from west of the Rocky Mountain Trench. Source rocks in the Omineca Crystalline Belt were being eroded as early as late early Albian and providing sediment into the foreland basin to the east.
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Cooke, Andy P., Quentin J. Fisher, Emma A. H. Michie, and Graham Yielding. "Permeability of carbonate fault rocks: a case study from Malta." Petroleum Geoscience 26, no. 3 (August 12, 2019): 418–33. http://dx.doi.org/10.1144/petgeo2019-055.
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The inherent heterogeneity of carbonate rocks suggests that carbonate-hosted fault zones are also likely to be heterogeneous. Coupled with a lack of host–fault petrophysical relationships, this makes the hydraulic behaviour of carbonate-hosted fault zones difficult to predict. Here we investigate the link between host rock and fault rock porosity, permeability and texture, by presenting data from series of host rock, damage zone and fault rock samples from normally faulted, shallowly buried limestones from Malta. Core plug X-ray tomography indicates that texturally heterogeneous host rocks lead to greater variability in the porosity and permeability of fault rocks. Fault rocks derived from moderate- to high-porosity (>20%) formations experience permeability reductions of up to six orders of magnitude relative to the host; >30% of these fault rocks could act as baffles or barriers to fluid flow over production timescales. Fault rocks derived from lower-porosity (<20%) algal packstones have permeabilities that are lower than their hosts by up to three orders of magnitude, which is unlikely to impact fluid flow on production timescales. The variability of fault rock permeability is controlled by a number of factors, including the initial host rock texture and porosity, the magnitude of strain localization, and the extent of post-deformation diagenetic alteration. Fault displacement has no obvious control over fault rock permeability. The results enable better predictions of fault rock permeability in similar lithotypes and tectonic regimes. This may enable predictions of across-fault fluid flow potential when combined with data on fault zone architecture.
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Ondrášik, Martin, and Miloslav Kopecký. "Rock Pore Structure as Main Reason of Rock Deterioration." Studia Geotechnica et Mechanica 36, no. 1 (March 1, 2014): 79–88. http://dx.doi.org/10.2478/sgem-2014-0010.
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Abstract Crashed or dimensional rocks have been used as natural construction material, decoration stone or as material for artistic sculptures. Especially old historical towns not only in Slovakia have had experiences with use of stones for construction purposes for centuries. The whole buildings were made from dimensional stone, like sandstone, limestone or rhyolite. Pavements were made especially from basalt, andesite, rhyolite or granite. Also the most common modern construction material - concrete includes large amounts of crashed rock, especially limestone, dolostone and andesite. However, rock as any other material if exposed to exogenous processes starts to deteriorate. Especially mechanical weathering can be very intensive if rock with unsuitable rock properties is used. For long it had been believed that repeated freezing and thawing in relation to high absorption is the main reason of the rock deterioration. In Slovakia for many years the high water absorption was set as exclusion criterion for use of rocks and stones in building industry. Only after 1989 the absorption was accepted as merely informational rock property and not exclusion. The reason of the change was not the understanding of the relationship between the porosity and rock deterioration, but more or less good experiences with some high porous rocks used in constructions exposed to severe weather conditions and proving a lack of relationship between rock freeze-thaw resistivity and water absorption. Results of the recent worldwide research suggest that understanding a resistivity of rocks against deterioration is hidden not in the absorption but in the structure of rock pores in relation to thermodynamic properties of pore water and tensile strength of rocks and rock minerals. Also this article presents some results of research on rock deterioration and pore structure performed on 88 rock samples. The results divide the rocks tested into two groups - group N in which the pore water does not freeze even when the temperature decreases to -20 ºC, and the second group F in which the pore water freezes. It has been found that the rocks from group N contain critical portion of adsorbed water in pores which prevents freezing of the pore water. The presence of adsorbed water enables thermodynamic processes related to osmosis which are dominantly responsible for deterioration of rocks from group N. A high correlation (R = 0.81) between content of adsorbed water and freeze-thaw loss was proved and can be used as durability estimator of rocks from group N. The rock deterioration of group F is caused not only by osmosis, but also by some other processes and influences, such as hydraulic pressure, permeability, grain size, rock and mineral tensile strength, degree of saturation, etc., and the deterioration cannot be predicted yet without the freeze-thaw test. Since the contents of absorbed water and ratio between adsorbed and bulk water (of which the absorbed water consists) is controlled by the porosity and pore structure, it can be concluded that the deterioration of some rocks is strongly related to rock pore structure.
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Liu, Xue Long, Na Zhang, Peng Wang, and Fu Cheng Yang. "Geochemical Characteristics and Genesis Discussion with Rock Metallogenic Belt of Geza Island Arc, Yunnan." Advanced Materials Research 1073-1076 (December 2014): 2015–18. http://dx.doi.org/10.4028/www.scientific.net/amr.1073-1076.2015.
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Geza island arc located in the southwest Sanjiang tectonic igneous rock belts which was a products of Ganzi-Litang oceanic crust diving to Zhongdian Landmasses in late Triassic. Lithogeochemical characteristics shown that the porphyry(porphyrite) and island-arc granite rocks have the same rock series (high-K calc-alkaline) and the same genetic type (I-type granite); these rocks trace elements similar to the granite of island arc,which enriched in Ba, La, Hf, Au,chalcophile elements Cu,Pb, siderophile elements Mo, Ni, and depleted in Rb, Nb, P, Ti. In this region, the similarities of porphyry and local acidic volcanic rocks in the main elements, REE and other trace elements and the composition suggest that they both have the same or similar magmatic source rocks. It is shown that the characteristics of the rock with the island arc granite partial melting of source rock, that may come from the arc type volcano rock or island arc volcano rock cognate magma evolution.
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Thandar Phyu, Hnin, Heru Hendrayana, I. Gde Budi Indrawan, and Toshitaka Kamai. "Simulation of Kalirejo Road Side Slope based on Altered Andesite Characters, Kulon Progo Regency, Indonesia." Journal of Applied Geology 5, no. 2 (January 18, 2021): 101. http://dx.doi.org/10.22146/jag.56916.
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ABSTRACT. This study is performed to investigate the characteristics of intrusive andesite rock consisting of Kalirejo Road Side Slope located in Kulon Progo Mountains. The rocks consisting the slope are identified by visual observation of hand specimens in the field, petrographic and X-ray Diffraction (XRD) analyses of the rock samples in the laboratory, upon which genetic rock classification is determined. The altered rock types are determined by the presence of specific minerals identified in the petrographic and XRD analyses. The alteration intensity is examined by comparing the amount of secondary minerals to the primary minerals observed in the petrographic and XRD analyses. The developments of rock weathering are determined in the field GSI classification based on the visual characteristics and in the laboratory-based on the Chemical Index of Alteration (CIA) and engineering properties of the altered rocks. The results show that the rocks typically consisted of 33.2 to 59.2% plagioclase, 1.4 to 5.1% quartz, therefore, are classified as andesite. The presence of halloysite, montmorillonite, and kaolinite as secondary minerals in the altered andesite indicated that the parent andesite rocks have undergone argillic alteration. Meanwhile, the percentages of primary minerals to secondary minerals indicate that the andesite rocks have undergone moderate to high alteration intensity. Based on the visual characteristics, the research area consisted of fresh, slight weathered andesite rocks and complete weathered residual soil. The CIA values of the samples are increased with the increase in rock weathering. Identification of visual characteristics of rock weathering appeared to be in good agreement with those classified based on the CIA and engineering properties analysis results. The uniaxial compressive strength (UCS) of rocks and soils is determined by point load tests. Engineering properties of the residual soils are performed by using ASTM standard procedures. In the lower part of the roadside, slope consists of fresh and slightly weathered andesite rocks, which have relatively high strength and are classified as medium strong rocks. Meanwhile, the upper part of the slope profile contained completely weathered residual soil, which had very low compressive strength, are classified as very weak soil.Keywords: andesite, argillic alteration, Geological Strength Index (GSI), hydrothermal alteration, roadside slope, weathering