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Weltje, Gert Jan, et Hilmar von Eynatten. « Quantitative provenance analysis of sediments : review and outlook ». Sedimentary Geology 171, no 1-4 (octobre 2004) : 1–11. http://dx.doi.org/10.1016/j.sedgeo.2004.05.007.
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Kinyua, A. M., T. Plummer, N. Shimizu, W. Melson et R. Potts. « Provenance of Kanjera Fossils by X-Ray Fluorescence and Ion Microprobe Analyses ». Advances in X-ray Analysis 35, B (1991) : 1165–73. http://dx.doi.org/10.1154/s0376030800013458.
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AbstractXRF and Ion mfcroprobe analyses of fossils of known and uncertain provenance from the Lower-Middle Pleistocene locality of Kanjera. Kenya, are reported. The goal of this study was to develop a nondestructive technique of provenancixig fossils, which could be applied to the Kanjera sample. The fossils of known provenance were collected in the excavations of the 1987 Smithsonian Expedition. Three fossils of uncertain provenance, two specimens of Theropithecus oswaldi and a hominid fossil, were analyzed as test cases.Both qualitative and quantitative XRF analyses of Kanjera fossils were carried out. In the qualitative analysis, the elemental peak areas from each fossil's XRF spectrum were calculated and normalized to the peak area of the incoherently scattered radiation. Results of the analysis showed that fossils from the Lower-Middle Pleistocene Kanjera Beds, for the most part, had higher levels of yttrium (Y) and zirconium (Zr) than those of the younger Apoko (Ap) Bed. black cotton soil (BCS) and modem bones (MD). The relative concentrations of uranium (U) v strontium (Sri and thorium (Th) were diagnostic of the Kanjera Bed of origin. These findings were confirmed by quantitative XRF and ion microprobe analyses of a subsample of Kanjera fossils. The T. oswaldi and hominid fossils had trace element concentrations suggestive of K2 and BCS provenances, respectively. These findings provide a framework for the qualitative XRF provenancing of other surface collected fossils from the locality.
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Muhammad Javed, Asif, Dorairaj Deivaseeno et Wickneswari Ratnam. « Characterization of natural provenances of Acacia mangium Willd. and Acacia auriculiformis A. Cunn. ex Benth. in Malaysia based on phenotypic traits ». Journal of Forest Science 63, No. 12 (12 décembre 2017) : 562–76. http://dx.doi.org/10.17221/82/2016-jfs.
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Acacia mangium Willdenow and Acacia auriculiformis A. Cunningham ex Bentham and their hybrid have become important planting species in Malaysia. Due to their high demand and consumption, development of high quality planting materials is desired. Conventional breeding of Acacia Miller is slow but the utilization of marker-assisted selection breeding can expedite the breeding process. Markers associated with quantitative trait loci (QTLs) required pedigreed populations whereas association mapping can be used directly on diverse germplasm. This study was conducted to screen provenances of A. mangium and A. auriculiformis of different geographical origins for their performance under the Malaysian environment. A. mangium exhibited superior traits compared to A. auriculiformis. More trait variation was observed within and between provenances of A. auriculiformis. Provenances from Queensland (QLD) were superior to those from Papua New Guinea (PNG) and Northern Territory. The best performing provenance with all three superior traits was from Claude River QTL of A. mangium and the worst was Bensbach Western Province, PNG belonging to A. auriculiformis. For individual traits like DBH, Morehead, PNG was superior. For plant height, Morehead, PNG was the superior provenance for A. mangium and Morehead River, QLD was from A. auriculiformis. For stem straightness the A. auriculiformis provenance Jardines Garden, QTL was superior to West of Morehead (PNG) for A. mangium. Multivariate analysis grouped provenances together based on similar traits and genetic similarity. These provenances can be used for seed families which can be treated as a homogeneous population for association mapping or for the development of segregating hybrid populations for Acacia breeding. For the purpose of utilization, provenances of A. mangium can be used for sawn timber. For fuelwood and charcoal industries, A. auriculiformis provenances should be preferred by selecting multi-stemmed trees. The most variable provenances with superior phenotypic traits can be integrated with the genotypic data e.g. single nucleotide polymorphism markers for association mapping to identify quantitative trait loci for marker-assisted breeding.
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VERHAEGEN, J., G. J. WELTJE et D. MUNSTERMAN. « Workflow for analysis of compositional data in sedimentary petrology : provenance changes in sedimentary basins from spatio-temporal variation in heavy-mineral assemblages ». Geological Magazine 156, no 07 (22 août 2018) : 1111–30. http://dx.doi.org/10.1017/s0016756818000584.
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AbstractThe field of provenance analysis has seen a revival in the last decade as quantitative data-acquisition techniques continue to develop. In the 20th century, many heavy-mineral data were collected. These data were mostly used as qualitative indications for stratigraphy and provenance, and not incorporated in a quantitative provenance methodology. Even today, such data are mostly only used in classic data tables or cumulative heavy-mineral plots as a qualitative indication of variation. The main obstacle to rigorous statistical analysis is the compositional nature of these data which makes them unfit for standard multivariate statistics. To gain more information from legacy data, a straightforward workflow for quantitative analysis of compositional datasets is provided. First (1) a centred log-ratio transformation of the data is carried out to fix the constant-sum constraint and non-negativity of the compositional data. Next, (2) cluster analysis is followed by (3) principal component analysis and (4) bivariate log-ratio plots. Several (5) proxies for the effects of sorting and weathering are included to check the provenance significance of observed variations and finally a (6) spatial interpolation of a provenance proxy extracted from the dataset can be carried out. To test this methodology, available heavy-mineral data from the southern edge of the Miocene North Sea Basin are analysed. The results are compared with available information from literature and are used to gain improved insight into Miocene sediment input variations in the study area.
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Zachariáš, Jiří, Aneta Kuchařová et Marek Kotrlý. « Provenance Analysis of Marbles by Combination of Cathodoluminescence Spectroscopy and Electron Microprobe Analyses—Methodological Comments ». Minerals 13, no 2 (9 février 2023) : 244. http://dx.doi.org/10.3390/min13020244.
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Various marbles from historic quarries of the Czech Republic were examined by means of cathodoluminescence (CL) spectroscopy (quantitative data) to determine the possible inclusion of the method in marble provenance studies. The methodology used was based on a combination of electron microprobe analysis (Ca, Mg, Fe and Mn composition) and CL spectroscopy (intensity) of calcite and dolomite grains of the marbles studied. Several statistical techniques were applied to the CL-spectra to find the most effective way of characterization of the CL-spectra for provenance discrimination. The combination of Mg-admixture of calcite and position of the maximum (i.e., centre) of a single Gaussian curve was revealed to be the most discriminative dependence of the marbles studied.
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Fu, Xiuli, Qi’an Meng, Yue Bai, Yangxin Su, Mingyu Jin, Zhengwang Huo, Hongxia Li et al. « Quantitative analysis of paleoenvironment of Qingshankou Formation in northern Songliao Basin, Northeastern China ». Interpretation 10, no 3 (6 juin 2022) : SD75—SD87. http://dx.doi.org/10.1190/int-2021-0153.1.
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The Qingshankou Formation in the Songliao Basin of northeastern China is an important layer for unconventional oil exploration. To solve the problem of the main controlling factors of shale oil enrichment, to quantitatively analyze the paleosalinity, paleoclimate, paleoredox environment, provenance, and lake productivity, and to clarify the relationship between sedimentary environment and total organic carbon, we have analyzed quantitative reconstruction of the sedimentary environment by using comprehensive analysis of multiple indicators with major and trace elements, fossils, and biomarkers. The results are as follows: the paleosalinity index w(Sr)/ w(Ba) ratio is 0.4–4, the w(B)/ w(Ga) value is 0.7–8.5, and the w(Pr)/ w(Ph) value is 0.8–2.8, which mainly stand for fresh brackish to saline water. The paleoclimate CIW′ (Chemical index of weathering, CIW = [A12O3/(AI203 + CaO+Na20)] × 100 [molecular proportions]) value is 90–100, indicating a warm and humid climate. The redox index w(V)/ w((V + Ni)) value is 0.54–0.89, which mainly belongs to the dysoxic environment. The provenance input of terrigenous debris index w(Ti)/ w(Al) value is 0.026–0.034, mainly standing for low terrigenous debris input. The production index CAL (enrichment degree of Cu) value is 1–3, belonging to high production. We conclude that the humid climate, the fresh brackish to saline and dysoxic water, and the high lake production provide favorable geologic conditions for biological reproduction and then provide a foundation for the formation, enrichment, and preservation of organic matter. The quantitative reconstruction of the paleoenvironment of the Qingshankou Formation has theoretical significance for Gulong shale oil exploration and development.
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Nguyen, Hiep Huu, Sang Nhu Pham, Hung The Khuong, Din Bui Dao, Bac Hoang Bui et Huy Quoc Chu. « A review of sediment provenance methods applied to the fluvial sediments in the East Sea based on clay mineralogy and Sr-Nd isotope ». Journal of Mining and Earth Sciences 63, no 4 (31 août 2022) : 45–60. http://dx.doi.org/10.46326/jmes.2022.63(4).05.
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Studying sediment provenance in the marine environment particularly plays an important role in interpretation of paleoclimate, lithology of the source regions as well as tectonism controlling weathering, erosion, transportation, and deposition processes (source-to-sink analysis). However, defining sediment sources and controlling elements require quantitative data and micro-analysis as they are influenced significantly by many factors such as lithology, tectonics, and climate condition in the source regions as well as sea-level changes, oceanic circulation, and their differential setting in the sea. A number of methods are employed to elucidate sediment provenance, but not all of them are useful in the East Sea. In this study, clay mineralogy and Sr-Nd isotope of sediment cores and surrounding river sediments in this region from previous studies are reused to evaluate their effectiveness in determining sediment provenance. In comparison between sediment cores and river sediments indicates that clay mineral assemblages and Sr-Nd isotopic composition of river sediments frequently contain feature information of the source regions that are preserved in marine sediments well, implying they contain valuable information of sediment provenance. Thus, these methods have been widely utilized to identify sediment provenance in the East Sea. This study displays that sediment provenance methods based on clay mineralogy and Sr-Nd isotope are effective tools in elucidating sediment provenance in the East Sea.
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Raymond, Carolyn A., J. F. G. Tibbits et M. Henson. « Genetic Variation Amongst and Within the Native Provenances of Pinus radiata D. Don in South-eastern Australia. 3. Molecular and Quantitative Structure ». Silvae Genetica 59, no 1-6 (1 décembre 2010) : 289–98. http://dx.doi.org/10.1515/sg-2010-0041.
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AbstractPatterns of differentiation between populations within a species can be examined using both molecular and quantitative data, with observed differences indicative of adaptation to local conditions. Pinus radiata D. Don (radiata pine) is a species of commercial importance in many countries but also listed as conservation dependent in its native range on the Californian coast and two off shore islands. This paper presents a comparative analysis of existing molecular data with new quantitative data from a large provenance/progeny trial in southeastern Australia. Microsatellite data was reanalysed using a Bayesian model to test whether the a priori assumption of five natural occurrences was valid. With the validity of the geographic structure confirmed, two further approaches were used to examine genetic structure 1. a comparative study of Fstand Qstestimates to investigate the role of drift and selection in shaping the differentiation between the populations for breeding traits and 2. population clustering based on both quantitative and molecular data. Results strongly support the hypothesis that the island provenances of Pinus radiata are distinctly different to the mainland provenances. The molecular evidence also indicates the island provenances are different to each other. However, these differences were not apparent for the quantitative traits related to tree growth and form. The two island populations were however, strongly differentiated from each other for wood density and acoustic velocity. The patterns of phenotypic differentiation of the island provenances for these wood traits are both consistent with, and greater than, that observed for the molecular data, providing some evidence for directional selection on these traits. This study provides a background for the interpretation of molecular studies aimed at detecting molecular signatures of selection and associating genetic variation within genes with these traits.
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Vicenzi, Edward, Meredith Sharps et Thomas Lam. « Quantitative Analysis of Obsidian and Determination of Source Provenance Using an Analytical Dual Beam SEM ». Microscopy and Microanalysis 27, S1 (30 juillet 2021) : 2560–63. http://dx.doi.org/10.1017/s1431927621009107.
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Caracciolo, L., S. Andò, P. Vermeesch, E. Garzanti, R. McCabe, M. Barbarano, C. Paleari, M. Rittner et T. Pearce. « A multidisciplinary approach for the quantitative provenance analysis of siltstone : Mesozoic Mandawa Basin, southeastern Tanzania ». Geological Society, London, Special Publications 484, no 1 (27 février 2019) : 275–93. http://dx.doi.org/10.1144/sp484-2018-136.
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AbstractThis paper shows how heavy minerals and single-grain varietal studies can be conducted on silt (representing c. 50% of world's sediments) sediments to obtain quantitative data as efficiently as for sand-sized sediments. The analytical workflows include heavy mineral separation using a wide grain-size window (15–355 μ) analysed through integrated optical analysis, Raman spectroscopy, QEMSCAN microscopy and U–Pb dating of detrital zircon. Upper Jurassic–Cretaceous silt-sized sediments from the Mandawa Basin of central-southern Tanzania have been selected for the scope of this research. Raman-aided heavy mineral analysis reveals garnet and apatite to be the most common minerals together with durable zircon, tourmaline and subordinate rutile. Accessory but diagnostic phases are titanite, staurolite, epidote and monazite. Etch pits on garnet and cockscomb features on staurolite document the significant effect of diagenesis on the pristine heavy mineral assemblage. Multivariate statistical analysis highlights a close association among durable minerals (zircon, tourmaline and rutile, ZTR) while garnet and apatite plot alone reflecting independence between the three groups of variables with garnet increasing in Jurassic samples. Raman data for garnet end-member analysis document different associations between Jurassic (richer in A, Bi and Bii types) and Cretaceous (dominant A, Ci and Cii types) samples. U–Pb dating of detrital zircon and their statistical integration with the above-mentioned datasets provide further insights into changes in provenance and/or drainage systems. Metamorphic rocks of the early and late Pan-African orogeny terranes of the Mozambique Belt and those of the Irumide Belt acted as main source of sediment during the Jurassic. Cretaceous sediments record a broadening of the drainage system reaching as far as the Usagran–Ubendian Belt and the Tanzanian Archean Craton.
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Shackley, M. Steven. « Sources of Archaeological Obsidian in the Greater American Southwest : An Update and Quantitative Analysis ». American Antiquity 60, no 3 (juillet 1995) : 531–51. http://dx.doi.org/10.2307/282264.
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Obsidian studies in the greater American Southwest have come of age. No longer does the region lag behind other adjoining regions both in the understanding of source provenance and the integración of obsidian source studies into regional designs. Most of the archaeological obsidian sources discussed here were originally presented in semi-quantitative form in this journal in 1988 (Shackley 1988a). The purpose here is to present that same data in broadly useable quantitative form calibrated to international standards, update the source descriptions when appropriate, and, finally, present data on a few new sources recently located. This is a necessary step to continue the momentum of obsidian studies in the region and make the information available to all. Finally, some discussion is directed toward the archaeological utility of obsidian studies in the region.
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Yue, Wei, Xiyuan Yue, Lingmin Zhang, Xianbin Liu et Jian Song. « Morphology of Detrital Zircon as a Fingerprint to Trace Sediment Provenance : Case Study of the Yangtze Delta ». Minerals 9, no 7 (17 juillet 2019) : 438. http://dx.doi.org/10.3390/min9070438.
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Deltaic areas and marginal seas are important archives that document information on regional tectonic movement, sea level rise, river evolution, and climate change. Here, sediment samples from boreholes of the Yangtze Delta and the modern Yangtze drainage were collected. A quantitative analysis of detrital zircon morphology was used to discuss the provenance evolution of the Yangtze Delta. This research demonstrated that a dramatic change in sediment provenance occurred in the transition from the Pliocene to Quaternary. Zircon grains in the Pliocene sediments featured euhedral crystals with large elongation (>3 accounted for 13.2%) and were closely matched to tributary samples in the Lower Yangtze (>3 accounted for 11.3%), suggesting sediment provenance from the proximal river basin. However, most detrital zircon grains of the Quaternary samples exhibited lower values of elongation and increased roundness (rounded grains were 9.4%), which was similar to those found in the modern Yangtze mainstream (rounded grains were 12.5%) and the middle tributaries (rounded grains were 7.0%). The decrease in zircon elongation and improvement of its roundness in the Quaternary strata implied that the Yangtze Delta received sediments of different provenance that originated from the Middle-Upper Yangtze basin due to the uplift of the Tibetan Plateau. Statistical analysis of detrital zircon morphology has proven useful for studying the source-to-sink of sediments.
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Rasser, Michael W., et James H. Nebelsick. « Provenance analysis of Oligocene autochthonous and allochthonous coralline algae : a quantitative approach towards reconstructing transported assemblages ». Palaeogeography, Palaeoclimatology, Palaeoecology 201, no 1-2 (décembre 2003) : 89–111. http://dx.doi.org/10.1016/s0031-0182(03)00512-1.
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CORRÊA, IRAN CARLOS STALLIVIERE, RICARDO NORBERTO AYUP ZOUAIN, JAIR WESCHENFELDER et LUIZ JOSÉ TOMAZELLI. « Áreas Fontes dos Minerais Pesados e sua Distribuição sobre a Plataforma Continental Sul-brasileira, Uruguaia e Norte-argentina ». Pesquisas em Geociências 35, no 1 (1 juillet 2008) : 137. http://dx.doi.org/10.22456/1807-9806.17899.
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The heavy mineral fraction of sedimentary rocks and sediments can provide important information about provenance in sedimentary basins studies because some minerals or group of minerals can be traced to a source rock or terrain of specific composition. This work is a provenance study based on heavy mineral analyses of samples collected on the Rio Grande do Sul (southern Brazil), Uruguay and north of Argentine continental shelf (between 29º30´ and 37º 30´ south latitude and 48º 30´ and 56º 30´ west longitude). The fine and very fine sand fractions (2-4 Φ) were selected for heavy mineral analysis employing bromoform (S.G.= 2.65). The quantitative analysis was made using a microscope for the mineral identification and the counting of 300 grains from each sample, in a total of 106 samples. Multivariate data analysis was applied for mineralogical analysis, principally the RQmode vector. Four principal assemblages were defined applying this technique revealing the main source as well as the dispersal patterns for the sediments. The first component was dominated by augite indicating a panpean-patagonic source. The second component was dominated by hornblende and hypersthene minerals, indicating a provenance from Precambrian terrains with basaltic influence. The third component was marked by the dominance of tourmaline, staurolite, epidote and kyanite reflecting a source from the Precambrian metamorphic terrains. Finally, the four components with apatite, zircon and sillimanite minerals were dispersed by the Rio de La Plata system.
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Costa, Joana, René E. Vaillancourt, Dorothy A. Steane, Rebecca C. Jones et Cristina Marques. « Microsatellite analysis of population structure in Eucalyptus globulus ». Genome 60, no 9 (septembre 2017) : 770–77. http://dx.doi.org/10.1139/gen-2016-0218.
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Eucalyptus globulus subsp. globulus Labill. (Tasmanian Blue Gum), native to southeast Australia, is a benchmark species for the pulp and paper industry. We genotyped 397 trees from 16 populations of E. globulus representing the native diversity in Australia using 24 microsatellite loci. Eight genetically distinct groups were detected, consistent with genetic groupings detected in previous quantitative and molecular studies. A sample of 29 Portuguese individuals was added to help clarify the origin of the Portuguese landrace. The results suggest a southern and eastern Tasmania origin for the Portuguese landrace. This genetic framework will enable researchers to investigate the provenance of individuals of unknown pedigree and assess the levels of representation of E. globulus natural variation in the Portuguese landrace.
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Mastley, Carrie P. « Representation of Black History in Archives : A Collection-Centered Quantitative Analysis of the Billups-Garth Archive ». Open Information Science 4, no 1 (20 août 2020) : 187–203. http://dx.doi.org/10.1515/opis-2020-0014.
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AbstractThis pilot study presents a collection-centered quantitative analysis of Black history resources available at the Billups-Garth Archive in Columbus, Mississippi. The Archive’s inventory lists for its record series and control files for its manuscript collections were assessed in order to determine the percentage of extant Black history resources in relation to the collection’s total holdings. Relevant collections were then evaluated to determine their mediums, subjects, and provenance. The results showed a dearth of collections related to Black history and indicated that very few were created by the Black community. Results also showed that most relevant resources were made up of textual documents as well as documents relating to everyday life and education. Overall, this study demonstrates how collection analyses may be undertaken to identify collection biases and collection deficiencies, especially deficiencies in representing the histories of marginalized communities.
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Zhu, Hongtao, Zhiwei Zeng, Hongliu Zeng, Changgui Xu et Fan Xiao. « Use of seismic-based new rose diagram to determine the major sediment-supply direction of progradational systems ». GEOPHYSICS 84, no 3 (1 mai 2019) : IM11—IM18. http://dx.doi.org/10.1190/geo2018-0133.1.
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A conventional method for identifying sediment-supply directions is to characterize the seismic progradational reflection configuration, which is based mainly on qualitative observation of numerous seismic profiles. We have developed a more quantitative and practical way to determine the major sediment-supply direction (MSSD) using a new type of rose diagram based on seismic progradational sequence angles. In accordance with similar principles of the rose diagram used in structural geology, we have developed an analytical method and a workflow for a new rose diagram of seismic-based progradational sequence angles to determine MSSD. The Bozhong sag, a subbasin of the Bohai Bay Basin with two typical progradational sequences (I and II), provides a suitable example to analyze MSSD and test the new method. Our result indicates that the MSSD of the two progradational sequences (I and II) corresponds to azimuths of 10°–20° and 340°–350°, respectively, intuitively indicating two sequences derived from different provenance-transport systems. The new rose diagram of seismic progradational angles offers a powerful and quantitative method for seismic-based sedimentary provenance and paleocurrent analysis.
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Jordan, Rebecca, Suzanne M. Prober, Ary A. Hoffmann et Shannon K. Dillon. « Combined Analyses of Phenotype, Genotype and Climate Implicate Local Adaptation as a Driver of Diversity in Eucalyptus microcarpa (Grey Box) ». Forests 11, no 5 (28 avril 2020) : 495. http://dx.doi.org/10.3390/f11050495.
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Trees are a keystone species in many ecosystems and a critical component of ecological restoration. Understanding their capacity to respond to climate change is essential for conserving biodiversity and determining appropriate restoration seed sources. Patterns of local adaptation to climate between populations within a species can inform such conservation decisions and are often investigated from either a quantitative trait or molecular genetic basis. Here, we present findings from a combined analysis of phenotype (quantitative genetic analysis), genotype (single nucleotide polymorphism (SNP) trait associations), and climate associations. We draw on the strength of this combined approach to investigate pre-existing climate adaptation and its genetic basis in Eucalyptus microcarpa (Grey box), an important tree for ecological restoration in south-eastern Australia. Phenotypic data from a 26-year-old provenance trial demonstrated significant genetic variation in growth and leaf traits at both the family and provenance levels. Growth traits were only associated with temperature, whilst leaf traits were associated with temperature, precipitation and aridity. Genotyping of 40 putatively adaptive SNPs from previous genome-wide analyses identified 9 SNPs associated with these traits. Drawing on previous SNP–climate association results, several associations were identified between all three comparisons of phenotype, genotype and climate. By combining phenotypic with genomic analyses, these results corroborate genomic findings and enhance understanding of climate adaptation in E. microcarpa. We discuss the implication of these results for conservation management and restoration under climate change.
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Sircombe, Keith N. « Quantitative comparison of large sets of geochronological data using multivariate analysis : a provenance study example from Australia ». Geochimica et Cosmochimica Acta 64, no 9 (mai 2000) : 1593–616. http://dx.doi.org/10.1016/s0016-7037(99)00388-9.
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Caracciolo, L. « Sediment generation and sediment routing systems from a quantitative provenance analysis perspective : Review, application and future development ». Earth-Science Reviews 209 (octobre 2020) : 103226. http://dx.doi.org/10.1016/j.earscirev.2020.103226.
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Torres-Valverde, José Marcos, José Ciro Hernández-Díaz, Artemio Carrillo-Parra, Eduardo Mendoza-Maya et Christian Wehenkel. « Provenance Trials of the Mexican Spruces in Nursery Conditions : Three Species Endangered by Climatic Variation ». Environmental Sciences Proceedings 3, no 1 (13 novembre 2020) : 12. http://dx.doi.org/10.3390/iecf2020-08080.
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The three Mexican spruces’ distribution is fragmented, which could lead to phenological, morphological and genetic differentiations, partially caused by local adaptation. In this study we examined the effect that climatic variables have on the growth and survival of 5641 Picea seedlings coming from eight seed provenances of three species and produced in identical nursery conditions, as a proxy of the genetic differentiation and adaptation among populations. A cluster analysis revealed: i) significant differences in the genetic quantitative traits among the three Picea species and ii) significant correlations among genetic quantitative traits and climatic factors.
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MEINHOLD, GUIDO, ANDREW C. MORTON, C. MARK FANNING et ANDREW G. WHITHAM. « U–Pb SHRIMP ages of detrital granulite-facies rutiles : further constraints on provenance of Jurassic sandstones on the Norwegian margin ». Geological Magazine 148, no 3 (24 novembre 2010) : 473–80. http://dx.doi.org/10.1017/s0016756810000877.
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AbstractElectron microprobe analyses of 128 detrital rutile grains from two Jurassic sandstone samples (Hettangian and Bajocian–Bathonian in age) from hydrocarbon exploration wells on the Norwegian margin confirm that more than 85 % of the rutiles were derived from metapelitic rocks. Zr-in-rutile geothermometry confirms that about 83 % of the rutile was formed under high-grade metamorphism (>750 °C). Sixty-two rutile grains, including 60 of the identified high-temperature rutile population, were also analysed for U–Pb geochronology using SHRIMP. The 206Pb–238U rutile ages range from approximately 485–292 Ma, with a major cluster between 450 and 380 Ma. These data suggest that the detrital rutile was predominantly derived from a felsic source that experienced granulite-facies metamorphism about 450–380 Ma ago. This conclusion is consistent with derivation from high-grade Caledonian metasedimentary rocks, probably the Krummedal sequence in central East Greenland, as previously suggested by an earlier provenance study using conventional heavy mineral analysis, garnet geochemistry and detrital zircon age dating. The present study underscores the importance of rutile geochemistry and geochronology in quantitative single-mineral provenance analysis of clastic sedimentary rocks.
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Leontopoulou, Georgia, Georgios E. Christidis, Grigorios Rousakis, Noémi S. Müller, George Papatheodorou et Maria Geraga. « Provenance analysis of sediments in the south-east Aegean during the Upper Quaternary : a composite approach based on bulk and clay mineralogy and geochemistry ». Clay Minerals 56, no 3 (septembre 2021) : 229–49. http://dx.doi.org/10.1180/clm.2022.2.
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AbstractSediments from the ST5 deep-sea bottom core collected from the south-east Aegean Sea between Symi and Tilos islands, Greece, were examined by quantitative mineralogical analysis and geochemical analysis to infer provenance and palaeoenvironmental control over sediment deposition. The mineralogical composition comprises carbonates (mainly calcite and Mg-calcite), quartz, feldspars, serpentine, amphibole and clay minerals. Chlorite is the most abundant clay mineral, whereas smectite and illite are less abundant than in the sediments in the south-west Aegean and the Cretan Sea. Semi-quantitative analysis of clay minerals from oriented clay fractions overestimates significantly the smectite content and underestimates the abundances of illite, chlorite and kaolinite. The studied sediments are enriched in MgO, Ni and Cr, which decrease in abundance with decreasing depth, following the distribution of serpentine. By contrast, the abundances of SiO2, Al2O3, Fe2O3, Na2O and K2O increase upcore. The regional S1 sapropel horizon is enriched in V and Co and has considerably greater Ba/Al ratios than the remaining sequence. The mineralogical and geochemical relationships indicate a strong ultrabasic influence, probably from the Marmaris ophiolite in the Lycian nappes. The clay mineral distribution suggests that the smectite was mainly of volcanogenic origin, the illite was supplied by the nearby landmasses of west Anatolia and the islands of Rhodes, Tilos and Symi and the contribution from the south-east Mediterranean was limited or totally lacking. The combined use of the mineralogical and geochemical analysis of bulk sediments rather than the clay fractions is not only extremely useful in tracing sediment provenance in relatively closed basins, but it also enables a more realistic assessment of the importance of water circulation patterns on sedimentation processes in such environments.
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Caracciolo, L., D. C. G. Ravidà, D. Chew, M. Janßen, N. K. Lünsdorf, W. A. Heins, S. Tobias et H. Stollhofen. « Reconstructing environmental signals across the Permian-Triassic boundary in the SE Germanic Basin : A Quantitative Provenance Analysis (QPA) approach ». Global and Planetary Change 206 (novembre 2021) : 103631. http://dx.doi.org/10.1016/j.gloplacha.2021.103631.
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Bermejo, Jesús, et Alejandro Quevedo. « The FortunaDomus(Cartagena, Spain) : An Archaeological Analysis of Household Activities in a Hispano-Roman Colonia ». European Journal of Archaeology 17, no 3 (2014) : 487–516. http://dx.doi.org/10.1179/1461957113y.0000000049.
Texte intégralRésumé :
This paper analyses the occupation sequence documented in the Roman house of La Fortuna (Cartagena, Spain). We use a contextual approach to study all the material culture documented in the domus. We start with a complete re-documentation of the stratigraphic record, in order to match the finds to their provenance. As a basis for this documentation, we discuss the abandonment typologies and the formation processes documented in the house. Using this framework we make a detailed examination of the artefact assemblages documented and we apply a quantitative study of the production, redistribution and consumption patterns during the different occupation phases. The ultimate objective of this paper is to provide a social and economic reading of the household activities carried out by the successive inhabitants in their own historical context.
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Dong, Zhicheng, Lina Zhang et Bingfu Jin. « Detrital Mica Composition Quantitatively Indicates the Sediment Provenance along the Subei Coast to the Yangtze Estuary ». Applied Sciences 12, no 24 (9 décembre 2022) : 12653. http://dx.doi.org/10.3390/app122412653.
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The influence of large rivers on the Subei littoral plain area requires more research than the results that have been available up to now. Thus, specific diagnostic indices of detrital mica are successfully applied for the first time to identify the detritus of the Yangtze River and the ancient Yellow River and to analyze their influence on the coast in the Subei littoral plain area. Based on field investigation and sample collection, detrital mica minerals within the 0.063–0.125 mm grain size fraction were selected and identified. Their content/ratio differentiations and possible origins were analyzed. Moreover, specific diagnostic indices were evaluated for detritus identification considering these two large rivers in addition to their provenance influences on the Subei littoral plain area. The results indicate that the detrital mica contents in the Yangtze River Estuary differed from those in the ancient Yellow River Estuary. The mass percentage in the former (average value of 32.2%) was much higher than that in the latter (average value of 13.1%). The former contained abundant weathered mica, with a particle percentage of approximately 50.6%, while the latter contained abundant biotite (with a particle percentage of approximately 40.9%). Differences, including but not limited to those above, could be attributed to basic geological, climatic and hydrodynamic conditions. In particular, the mica indices were clearly distinguished between these two river estuaries. These indices constitute specific diagnostic indices for differentiating river detritus and quantitative contribution analysis of detritus provenance in the Subei littoral plain area. Finally, the changes and quantitative contributions of four diagnostic indices demonstrated that in the Subei littoral plain area, northward from the Yangtze River Estuary to sample site SBY11 located in Yangkou town, Rudong County, detrital micas were mainly affected by the Yangtze River, and southward from the ancient Yellow River Estuary to sample site SBY12 located in Bengcha town, Rudong County, detrital micas were largely affected by the ancient Yellow River. The main mixing area should be located between these two towns. This study provides both a good example and an efficient approach to the application of detrital mica in detritus identification, mixed zone determination, sediment provenance analysis and transport tracing.
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Germinario, Luigi, Roberto Cossio, Lara Maritan, Alessandro Borghi et Claudio Mazzoli. « Textural and Mineralogical Analysis of Volcanic Rocks by µ-XRF Mapping ». Microscopy and Microanalysis 22, no 3 (10 mai 2016) : 690–97. http://dx.doi.org/10.1017/s1431927616000714.
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AbstractIn this study, µ-XRF was applied as a novel surface technique for quick acquisition of elemental X-ray maps of rocks, image analysis of which provides quantitative information on texture and rock-forming minerals. Bench-top µ-XRF is cost-effective, fast, and non-destructive, can be applied to both large (up to a few tens of cm) and fragile samples, and yields major and trace element analysis with good sensitivity. Here, X-ray mapping was performed with a resolution of 103.5 µm and spot size of 30 µm over sample areas of about 5×4 cm of Euganean trachyte, a volcanic porphyritic rock from the Euganean Hills (NE Italy) traditionally used in cultural heritage. The relative abundance of phenocrysts and groundmass, as well as the size and shape of the various mineral phases, were obtained from image analysis of the elemental maps. The quantified petrographic features allowed identification of various extraction sites, revealing an objective method for archaeometric provenance studies exploiting µ-XRF imaging.
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Chiemezie, Ohanyiri C., et Omotowo B. Aminat. « Geochemical assessment of claystone deposits from the Patti Formation, Southern Bida Basin, Nigeria ». Materials and Geoenvironment 65, no 4 (1 décembre 2018) : 207–18. http://dx.doi.org/10.2478/rmzmag-2018-0018.
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AbstractGeochemical studies of claystone deposits from the Patti Formation in the southern Bida Basin, north-Central Nigeria, were carried out on representative samples to determine the basin’s depositional conditions, provenance and tectonic setting. The localities within the study area included Gegu, Ahoko, Ahoko-Etigi, Omu and Idu.Semi-quantitative phase analysis using the Rietveld method and X-ray powder diffraction data revealed that the claystone samples had prominent kaolinite with other constituents such as quartz, illite–muscovite, K-feldspar, pyrite, marcasite, anatase, rutile and gorceixite.Enrichment of Al2O3, Ba, Th, Sr, Cr and La suggests that these elements are primarily controlled by the dominant clay minerals.Geochemical parameters such as U, U/Th, Ni/Co, V/Cr and Cu/Zn ratios strongly implied that these claystones were deposited in an oxidising environment. Provenance deducing ratios for felsic, mafic and basic igneous rocks were compared. Al2O3/TiO2 ratio suggested intermediate to felsic rocks as the probable source rocks for the claystone samples; however, Y/Ni, Cr/V, La/Sc and Th/Sc ratios suggested a felsic progenitor. The tectonic discrimination diagram showed that the samples’ plot was within the region specified for passive margin-type tectonic setting.
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Oszczypko-Clowes, Marta, Patrycja Wójcik-Tabol et Mateusz Płoszaj. « Source areas of the Grybów sub-basin : micropaleontological, mineralogical and geochemical provenance analysis (Outer Western Carpathians, Poland) ». Geologica Carpathica 66, no 6 (1 décembre 2015) : 515–34. http://dx.doi.org/10.1515/geoca-2015-0042.
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Abstract The Grybów Unit occurring in the Ropa tectonic window was the subject of micropaleontological and geochemical investigation. Studies, based on calcareous nannofossils, proved that the level of reworked microfossil is not higher than 22 % and it varies between two sections. Quantitative analyses of the reworked assemblages confirmed the domination of Cretaceous and Middle Eocene species. The Sub-Grybów Beds, Grybów Marl Formation and Krosno Beds were assigned to the Late Oligocene and represent the terminal flysch facies. Detrital material accumulated in the Oligocene sediments originated from the Marmarosh Massif, which is the eastern prolongation of the Fore-Magura Ridge. The microscopically obtained petrological features agree with the chemical composition of the samples. Mica flakes, rounded grains of glauconite, heavy mineral assemblage, including abraded grains of zircon, rutile and tourmaline as well as charred pieces of plant tissues are reworked components. Enrichment in zircon and rutile is confirmed geochemically by positive correlation between Zr and SiO2. Zr addition is illustrated on 10×Al2O3–Zr–200×TiO2 and Zr/Sc vs. Th/Sc diagrams. Interpretation of the A–CN–K diagram and variety of CIA and CPA values indicate that the source rocks were intensely weathered granite-type rocks.
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Vetrimurugan, E., M. P. Jonathan, S. K. Sarkar, Francisco Rodríguez-González, Priyadarsi D. Roy, S. Velumani et J. S. Sakthi. « Occurrence, distribution and provenance of micro plastics : A large scale quantitative analysis of beach sediments from southeastern coast of South Africa ». Science of The Total Environment 746 (décembre 2020) : 141103. http://dx.doi.org/10.1016/j.scitotenv.2020.141103.
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Ortiz, Joseph D., Leonid Polyak, Jacqueline M. Grebmeier, Dennis Darby, Dennis D. Eberl, Sathy Naidu et Doron Nof. « Provenance of Holocene sediment on the Chukchi-Alaskan margin based on combined diffuse spectral reflectance and quantitative X-Ray Diffraction analysis ». Global and Planetary Change 68, no 1-2 (juillet 2009) : 73–84. http://dx.doi.org/10.1016/j.gloplacha.2009.03.020.
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Dwiyanti, F. G., I. Z. Siregar et U. J. Siregar. « Phenotypic and Genetic Diversity Evaluation of Sengon (Falcataria moluccana (Miq.) Barneby & ; JW Grimes) from Solomon Provenance on Progeny Trial in Cirangsad Experimental Forest, West Java ». Jurnal Manajemen Hutan Tropika (Journal of Tropical Forest Management) 27, no 3 (14 décembre 2021) : 174–83. http://dx.doi.org/10.7226/jtfm.27.3.174.
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Initial evaluation of phenotypic variability and genetic diversity was conducted on the progeny test of 2 years-old sengon from Solomon provenance, which derived from nine families of mother tree and were then planted in 4 blocks in the Cirangsad Experimental Forest. Phenotypic assessment on eight traits was conducted on 36 trees using a scoring system, while genetic diversity of 15 selected individuals which represented high and low-score phenotypic traits was analyzed using 5 selected RAPD primers. The result on phenotypic assessment showed that family 3 (57.25 points) has the highest average score of phenotypic quality and family 4 has the lowest average score (7.50 points). Furthermore, genetic analysis showed that the low-scoring sengon population had a greater mean genetic diversity (He = 0.2535) than the high-score population (He = 0.2345). The analysis of molecular variance (AMOVA) revealed a significant genetic differences (p-value < 0.001) among high and low-score populations and the dendrogram of genetic distance revealed clustering of individuals having similar superior phenotypic against those having non-superior, indicating the selection based on phenotypes in this study had succeeded in pooling the good quantitative alleles in the selected population. This evaluation results can be used as a reference in determining the best families to produce superior sengon (from Solomon provenance) offspring in the future that have desired adaptability, productivity, and diversity.
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Wang, Shengdong, Xiaohong Deng, Peng Dai, Junjie Wu, Jie Zhang, Quan Zhang et Zhong Wang. « Geochemistry and mineralogy of Quaternary sediments in the northern Bohai Bay Basin, North China : implications for provenance and climate change ». Canadian Journal of Earth Sciences 57, no 3 (mars 2020) : 396–406. http://dx.doi.org/10.1139/cjes-2018-0213.
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The Bohai Bay Basin, located in the eastern North China Block, is an important sedimentary basin for studying the Quaternary climate and environment of northern China. Although sporo-pollen analyses have been used to study the paleoclimate, quantitative research via geochemistry had not been conducted. The sedimentary sequence, geochemistry, and mineralogy of Quaternary sediments from core GJ01 in the Yongding River fluvial plain, northern Bohai Bay Basin, were studied to determine their provenance and investigate climate change during the Quaternary. The stratigraphic sequence of the Quaternary was mainly formed by fluviation by a meandering river, showing a typical dual structure. The sediments have relatively high SiO2 and CaO concentrations, and low Al2O3, Na2O, and Fe2O3T concentrations. In terms of trace elements, most large ion lithophile elements are slightly enriched, and Rb and K concentrations are close to those of post-Archean Australian shale (PAAS); most high field strength elements are slightly to moderately depleted. Rare earth elements (REEs) vary significantly, with light rare earth elements (LREEs) obviously enriched relative to heavy rare earth elements (HREEs). A slightly negative Eu anomaly is present, with nearly no Ce anomaly. Mineralogical analysis shows that the main minerals in the fine-grained sediments are quartz, plagioclase, and K-feldspar. The geochemistry and mineralogy of the sediments indicate that the main provenances were recycled sedimentary rocks and felsic igneous rocks. The sediments have low chemical index of alteration (CIA) values, demonstrating that the source rocks underwent slight weathering. The mean annual precipitation and temperature of the studied area during the Quaternary varied from 531 to 875 mm and from 4.1 to 11.8 °C, respectively.
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Worden, R. H., James E. P. Utley, Alan R. Butcher, J. Griffiths, L. J. Wooldridge et A. Y. Lawan. « Improved imaging and analysis of chlorite in reservoirs and modern day analogues : new insights for reservoir quality and provenance ». Geological Society, London, Special Publications 484, no 1 (19 décembre 2018) : 189–204. http://dx.doi.org/10.1144/sp484.10.
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AbstractChlorite is a key mineral in the control of reservoir quality in many siliciclastic rocks. In deeply buried reservoirs, chlorite coats on sand grains prevent the growth of quartz cements and lead to anomalously good reservoir quality. By contrast, an excess of chlorite – for example, in clay-rich siltstone and sandstone – leads to blocked pore throats and very low permeability. Determining which compositional type is present, how it occurs spatially, and quantifying the many and varied habits of chlorite that are of commercial importance remains a challenge. With the advent of automated techniques based on scanning electron microscopy (SEM), it is possible to provide instant phase identification and mapping of entire thin sections of rock. The resulting quantitative mineralogy and rock fabric data can be compared with well logs and core analysis data. We present here a completely novel Quantitative Evaluation of Minerals by SCANning electron microscopy (QEMSCAN®) SEM–energy-dispersive spectrometry (EDS) methodology to differentiate, quantify and image 11 different compositional types of chlorite based on Fe : Mg ratios using thin sections of rocks and grain mounts of cuttings or loose sediment. No other analytical technique, or combination of techniques, is capable of easily quantifying and imaging different compositional types of chlorite. Here we present examples of chlorite from seven different geological settings analysed using QEMSCAN® SEM–EDS. By illustrating the reliability of identification under automated analysis, and the ability to capture realistic textures in a fully digital format, we can clearly visualize the various forms of chlorite. This new approach has led to the creation of a digital chlorite library, in which we have co-registered optical and SEM-based images, and validated the mineral identification with complimentary techniques such as X-ray diffraction. This new methodology will be of interest and use to all those concerned with the identification and formation of chlorite in sandstones and the effects that diagenetic chlorite growth may have had on reservoir quality. The same approach may be adopted for other minerals (e.g. carbonates) with major element compositional variability that may influence the porosity and permeability of sandstone reservoirs.
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Andrews, John T. « Baffin Bay/Nares Strait surface (seafloor) sediment mineralogy : further investigations and methods to elucidate spatial variations in provenance ». Canadian Journal of Earth Sciences 56, no 8 (août 2019) : 814–28. http://dx.doi.org/10.1139/cjes-2018-0207.
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The goal of the paper is to ascertain whether there are significant regional variations in sediment mineral composition that might be used to elucidate ice sheet histories. The weight percentages of nonclay and clay minerals were determined by quantitative X-ray diffraction. Cluster analysis, an unsupervised learning approach, is used to group sediment mineralogy of 263 seafloor/core top samples between ∼80°N and 62°N. The optimum number of clusters, based on 30 indexes, was three for the weight percentage data but varied with data transformations. Maps of the distribution of the three mineral clusters or facies indicate a significant difference in weight percentages between samples from the West Greenland and Baffin Island shelves. However, several indexes support a larger number of clusters and similar analyses of the spatial distribution and defining minerals of nine mineral facies indicated a strong association with the original three clusters and with broad geographic designations (i.e., West Greenland shelf, Baffin Island fiords, etc). Classification Decision Tree analysis indicates that this difference is primarily controlled by the percentages of plagioclase feldspars versus alkali feldspars.
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Zhang, Kaixuan, Dan Wang, Chuanping Yang, Guanjun Liu, Guifeng Liu, Hanguo Zhang, Lian Lian et Zhigang Wei. « Linkage map construction and QTL analysis for Betula platyphylla Suk using RAPD, AFLP, ISSR and SSR ». Silvae Genetica 61, no 1-6 (1 décembre 2012) : 1–9. http://dx.doi.org/10.1515/sg-2012-0001.
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AbstractA linkage map for Betula platyphylla Suk was constructed based on RAPD, ISSR, AFLP and SSR markers by a pseudo-testcross mapping strategy. A F1segregating population including 80 progenies was obtained from the cross between two superior trees selected from Qinghai and Wangqing provenance, respectively. The paternal map was constructed with 282 markers consisting of 14 major and 15 minor (5 triplets and 10 doublets) linkage groups and spanning 1131 cM at an average distance of 4.0 cM between adjacent markers. The maternal map has 277 markers consisting of 15 major and 8 minor (5 triplets and 3 doublets) groups covering 1288 cM at an average distance of 4.6 cM between adjacent markers. In the same pedigree we investigated association of genetic markers with seedling stem height and circumference. The composite interval mapping was used to detect the number of quantitative trait loci and their position on the genetic linkage maps. Three QTLs (one on the male map and two on the female map) were found explaining 13.4%, 17.5% and 18.8% of the trait variation, respectively.
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Devlin, Liam. « Antiquity market trends in Cycladic figurines, 2000–19 : Studies in price, prevalence, and provenance ». International Journal of Cultural Property 29, no 3 (août 2022) : 311–44. http://dx.doi.org/10.1017/s0940739122000224.
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AbstractWhile the illicit trade in Cycladic figurines is a well-known phenomenon, and the escalatory impact of auction sales upon the looting of Cycladic deposits is widely accepted, there has been to date no systematic study of commercial transactions in Cycladic figurines. This study addresses this gap by performing a quantitative market analysis of auction house sales in Cycladic figurines between 2000 and 2019, examining the frequency with which they appear on the market, fluctuations in their price, and the nature of their provenance. In doing so, it sets out a methodology for navigating the ambiguous nature of antiquity market data, which can often give the misleading impression of a reforming market if the latent commercial contexts are not considered. Overall, a comprehensive insight is gained into the present state of the antiquities market in Cycladic figurines. This insight contributes much needed empirical data on the illicit antiquities trade and offers a new interpretative methodology that can be incorporated in future studies that seek to understand the true nature of antiquity market data.
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Harper, Kyle. « The Greek Census Inscriptions of Late Antiquity ». Journal of Roman Studies 98 (novembre 2008) : 83–119. http://dx.doi.org/10.3815/007543508786239661.
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This article reconsiders a set of Late Roman inscriptions which record the tax liabilities of dozens of landowners in terms of post-Diocletianic fiscality. The stones, from eleven cities in the Aegean and western Asia Minor, are evaluated as evidence for the social and economic history of the Late Empire, challenging Jones' fundamental study in which the inscriptions are read as a sign of structural crisis. With their non-Egyptian provenance, the inscriptions offer unique, quantitative insights into land-ownership and labour. The inscriptions reveal surprising levels of slave labour in the eastern provinces, particularly in a new inscription from Thera. This last document allows, for the first time, an empirical analysis of the demographics of an estate-based population of slaves in antiquity.
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Page, Virginia M. « Anatomical Variation in the Wood of Robinia Pseudoacacia L. and the Identity of Miocene Fossil Woods from Southwestern United States ». IAWA Journal 14, no 3 (1993) : 299–314. http://dx.doi.org/10.1163/22941932-90001333.
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A detailed analysis of selected quantitative features was made of secondary xylem from the trunk, branch, and root of a specimen of Robinia pseudoacacia L. The analysis serves as a basis for interpreting two suites of fossil woods closely similar to the wood of Robinia. One assemblage had its provenance in western Nevada and the other in southern California. Results of the survey show considerable overlap in ranges of variation in the fossils and extant woods. These findings parallel results of a similar investigation by Matten et al. (1977). Woods from both fossil localities fall within the specifications of the organ species Robinia zirkellii (Platen) Matten, Gastaldo ' Lee. The survey also revealed the kinds of differences that may be found in species of Robinia growing in dissimilar habitats. Differences noted among trunk, branch and root wood of extant Robinia make it possible to distinguish these organs among the fossils.
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Li, Tingwei, Zhenxue Jiang, Chenlu Xu, Yuan Yuan, Pengfei Wang, Guoheng Liu, Bo Zhang, Chuanxiang Ning et Zhi Wang. « Effect of sedimentary environment on shale lithofacies in the lower third member of the Shahejie Formation, Zhanhua Sag, eastern China ». Interpretation 5, no 4 (30 novembre 2017) : T487—T501. http://dx.doi.org/10.1190/int-2017-0016.1.
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Research on shale lithofacies is important for shale oil and gas production. This study focused on the lower third member of the Shahejie Formation ([Formula: see text]) in the Luo-69 well in the Zhanhua Sag, Jiyang Depression, Bohai Bay Basin, eastern China. Several methods, including thin section observations, total organic carbon (TOC) analysis, X-ray diffraction analysis, quantitative evaluations of minerals by scanning electron microscopy, major and trace-element analyses, and field emission-scanning electron microscopy, are used to investigate the effect of sedimentary environment on the type and distribution of shale lithofacies. Our research indicates that 36 types of shale lithofacies can be classified based on the TOC content, mineral composition, and sedimentary structure, of which five types are identified in the study area. The [Formula: see text] shale has a high calcareous mineral content (average of 49.64%), low clay and siliceous minerals contents (averages of 19.54% and 19.02%, respectively), a high TOC content (average of 3.00 wt%), and well-developed horizontal bedding. The sedimentary environment during the deposition of the [Formula: see text] shale in the Zhanhua Sag had a warm and moist climate, limited provenance, saline water, and strong reducibility. The sedimentary environment in the early stage had a drier climate, more limited provenance, higher salinity, and stronger reducibility than that in the later stage. Shale lithofacies can reflect a certain sedimentary environment and depositional process; similarly, a depositional environment controls the type and distribution of shale lithofacies. Due to the characteristics of the [Formula: see text] sedimentary environment, organic-rich massive mixed shale, organic-rich bedded mixed-calcareous shale, organic-rich laminated calcareous shale, and organic-fair laminated calcareous shale are developed in the [Formula: see text] formation from top to bottom.
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BOKO-HAYA, Yves Yatindo, Christine A. I. N. OUINSAVI, Yanick Y. AKIN et Clément AGBANGLA. « Influence of geographic provenance on phenotypic variation in seed and kernel traits of the African oil tree from southern Benin and implications for species breeding ». Nova Geodesia 2, no 4 (28 décembre 2022) : 76. http://dx.doi.org/10.55779/ng2476.
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Knowledge of oilseeds plants’ traits and features is fundamental to understanding the natural selection process and improving conservation programs through species selection. As a forest oilseed, Ricinodendron heudelotii is the object of growing interest among value chain actors, who are increasingly interested in its intrinsic characteristics. To date, there is a lack of information on plant morphological traits for the selection of the best genotype, especially as far as seed and kernel traits are concerned. The aim of this study was to make a typology and establish the relationship between seed and kernel traits of Ricinodendron heudelotii, depending on provenances represented by wild populations of trees in southern Benin. We sampled the provenances constituted equally and per tree, ten random samples each of fruits, seeds, kernels, and shells were collected for measurement. Hierarchical classification, common component analysis, Pearson’s, and Chi-square association tests were performed for statistical analysis. Substantial variation between seed and kernel traits was observed between and within provenances. High coefficients of variation for the quantitative descriptors (length, width, and mass) of seeds and kernels appear to be the essential traits that discriminate the plant into two morphotypes. Furthermore, seed and kernel characteristics show a significant positive correlation with these discrimination criteria. The upper morphotype contains accessions from three provenances with huge seeds and kernels but few seeds per fruit, while the lower morphotype includes the other provenances with tiny seeds and kernels. The results of the study provided essential information that could be an avenue for improvement with further biochemical and molecular characterization studies.
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Itano, Keita, Kenta Ueki, Tsuyoshi Iizuka et Tatsu Kuwatani. « Geochemical Discrimination of Monazite Source Rock Based on Machine Learning Techniques and Multinomial Logistic Regression Analysis ». Geosciences 10, no 2 (6 février 2020) : 63. http://dx.doi.org/10.3390/geosciences10020063.
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Detrital monazite geochronology has been used in provenance studies. However, there are complexities in the interpretation of age spectra due to their wide occurrence in both igneous and metamorphic rocks. We use the multinomial logistic regression (MLR) and cross-validation (CV) techniques to establish a geochemical discrimination of monazite source rocks. The elemental abundance-based geochemical discrimination was tested by selecting 16 elements from granitic and metamorphic rocks. The MLR technique revealed that light rare earth elements (REEs), Eu, and some heavy REEs are important discriminators that reflect elemental fractionation during magmatism and/or metamorphism. The best model yielded a discrimination rate of ~97%, and the CV method validated this approach. We applied the discrimination model to detrital monazites from African rivers. The detrital monazites were mostly classified as granitic and of garnet-bearing metamorphic origins; however, their proportion of metamorphic origin was smaller than the proportion that was obtained by using the elemental-ratio-based discrimination proposed by Itano et al. in Chemical Geology (2018). Considering the occurrence of metamorphic rocks in the hinterlands and the different age spectra between monazite and zircon in the same rivers, a ratio-based discrimination would be more reliable. Nevertheless, our study demonstrates the advantages of machine-learning-based approaches for the quantitative discrimination of monazite.
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Stöhr, Mark R., Andreas Günther et Raphael W. Majeed. « The Collaborative Metadata Repository (CoMetaR) Web App : Quantitative and Qualitative Usability Evaluation ». JMIR Medical Informatics 9, no 11 (29 novembre 2021) : e30308. http://dx.doi.org/10.2196/30308.
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Background In the field of medicine and medical informatics, the importance of comprehensive metadata has long been recognized, and the composition of metadata has become its own field of profession and research. To ensure sustainable and meaningful metadata are maintained, standards and guidelines such as the FAIR (Findability, Accessibility, Interoperability, Reusability) principles have been published. The compilation and maintenance of metadata is performed by field experts supported by metadata management apps. The usability of these apps, for example, in terms of ease of use, efficiency, and error tolerance, crucially determines their benefit to those interested in the data. Objective This study aims to provide a metadata management app with high usability that assists scientists in compiling and using rich metadata. We aim to evaluate our recently developed interactive web app for our collaborative metadata repository (CoMetaR). This study reflects how real users perceive the app by assessing usability scores and explicit usability issues. Methods We evaluated the CoMetaR web app by measuring the usability of 3 modules: core module, provenance module, and data integration module. We defined 10 tasks in which users must acquire information specific to their user role. The participants were asked to complete the tasks in a live web meeting. We used the System Usability Scale questionnaire to measure the usability of the app. For qualitative analysis, we applied a modified think aloud method with the following thematic analysis and categorization into the ISO 9241-110 usability categories. Results A total of 12 individuals participated in the study. We found that over 97% (85/88) of all the tasks were completed successfully. We measured usability scores of 81, 81, and 72 for the 3 evaluated modules. The qualitative analysis resulted in 24 issues with the app. Conclusions A usability score of 81 implies very good usability for the 2 modules, whereas a usability score of 72 still indicates acceptable usability for the third module. We identified 24 issues that serve as starting points for further development. Our method proved to be effective and efficient in terms of effort and outcome. It can be adapted to evaluate apps within the medical informatics field and potentially beyond.
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Chmielewski, Jerry G. « Antennaria howellii subsp. gaspensis comb, et stat. nov. (Asteraceae : Inuleae) : justification for change ». Canadian Journal of Botany 73, no 9 (1 septembre 1995) : 1366–70. http://dx.doi.org/10.1139/b95-148.
Texte intégralRésumé :
Canonical discriminant analysis was used to assess the taxonomic status of Antennaria neodioica Greene var. gaspensis Fernald. Results based on these analyses indicate that Antennaria howellii Greene, Antennaria microphylla Rydberg, A. neodioica var. gaspensis, Antennaria pulvinata Greene, and Antennaria rosea Greene are morphologically distinct. High cross-validation assignment rates as well as high Geisser assignment probabilities for each of the taxa support this statement. Elevating var. gaspensis to the rank of species is in part supported by the data analysis, but doing so would be contrary to the species standard method and inconsistent with recent practice in revisions of the genus. The presence of scarious appendages at the tips of the upper cauline leaves, the open pedicellate inflorescence, the whitish-green capitula, general growth form, agamospermous reproduction, chromosome number, provenance, and quantitative morphology, in addition to the results of the canonical discriminant analysis, support recognition of var. gaspensis at an infraspecific rank. In keeping with the criteria utilized in recent revisions of the genus, var. gaspensis should more appropriately be treated as a subspecies. Recent nomenclatural rearrangements in A. neodioica and A. howellii founded on the priority of the latter lead to the following new combination: Antennaria howellii subsp. gaspensis (Fernald) Chmielewski. Key words: Antennaria howellii var. gaspensis, Asteraceae, Newfoundland flora, Gaspé Bay Peninsula flora.
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Koh, James, Joyce A. Hogue, Sanziana A. Roman, Randall P. Scheri, Hèléne Fradin, David L. Corcoran et Julie A. Sosa. « Transcriptional profiling reveals distinct classes of parathyroid tumors in PHPT ». Endocrine-Related Cancer 25, no 4 (avril 2018) : 407–20. http://dx.doi.org/10.1530/erc-17-0470.
Texte intégralRésumé :
The clinical presentation of primary hyperparathyroidism (PHPT) varies widely, although the underlying mechanistic reasons for this disparity remain unknown. We recently reported that parathyroid tumors can be functionally segregated into two distinct groups on the basis of their relative responsiveness to ambient calcium, and that patients in these groups differ significantly in their likelihood of manifesting bone disability. To examine the molecular basis for this phenotypic variation in PHPT, we compared the global gene expression profiles of calcium-sensitive and calcium-resistant parathyroid tumors. RNAseq and proteomic analysis identified a candidate set of differentially expressed genes highly correlated with calcium-sensing capacity. Subsequent quantitative assessment of the expression levels of these genes in an independent cohort of parathyroid tumors confirmed that calcium-sensitive tumors cluster in a discrete transcriptional profile group. These data indicate that PHPT is not an etiologically monolithic disorder and suggest that divergent molecular mechanisms could drive the observed phenotypic differences in PHPT disease course, provenance, and outcome.
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AIT AABD, Naima, Fouad MSANDA et Abdelhamid EL MOUSADIK. « Univariate and Multivariate Analysis of Agronomical Traits of Preselected Argan Trees ». Notulae Botanicae Horti Agrobotanici Cluj-Napoca 40, no 2 (5 novembre 2012) : 308. http://dx.doi.org/10.15835/nbha4028209.
Texte intégralRésumé :
A collection of thirty argan trees (Argania spinosa (L.) Skeels), representing the Aoulouz provenance in southwest of Morocco were used to study genetic variability and selection for three years. In this study, the genetic diversity of thirty genotypes (tree mothers) of argan (Argania spinosa) collected from Aoulouz was evaluated using agro-morphological characters. The main objective of the study was to assess and describe with multivariate analysis the genetic diversity in order to select good candidate trees for a future breeding program. The results obtained showed a large variation for all the traits examined. Analysis of variance using general linear model provided a significant variation between genotypes. Furthermore, genotypic and phenotypic variances for quantitative traits, particularly for seed length, seed width, almond length and oil content were higher. Phenotypic coefficient of variation was higher than genotypic coefficient of variation for all the characters. High heritability was recorded for oil content (97.90%), seed width (72.68%) and seed length (57.55%) respectively, indicating the additive gene action. In addition, a three dimensional plot based on principal coordinate analysis method was used to evaluate the performance genotypes as to the production of oil for three years. The genotypes ‘Ao-12R’, ‘Ao-7R’, ‘Ao-4R’, ‘Ao-4V’, ‘Ao-11R’, ‘Ao-8V’ and ‘Ao-7V’ were found to be the best for high oil content. Identification and selection with superior agronomic traits may be an effective method for genetic improvement of argan trees, and a first step for further breeding studies.
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Ibrahim Bio Yerima, Abdou R., Enoch G. Achigan-Dako, Mamadou Aissata, Emmanuel Sekloka, Claire Billot, Charlotte O. A. Adje, Adeline Barnaud et Yacoubou Bakasso. « Agromorphological Characterization Revealed Three Phenotypic Groups in a Region-Wide Germplasm of Fonio (Digitaria exilis (Kippist) Stapf) from West Africa ». Agronomy 10, no 11 (27 octobre 2020) : 1653. http://dx.doi.org/10.3390/agronomy10111653.
Texte intégralRésumé :
Fonio is an ancient orphan cereal, cultivated by resource-poor farmers in arid and semi-arid regions of West Africa, who conserved and used the cereal for nutrition and income generation. However, the extent and patterns of phenotypic variation within the fonio germplasm remain scarcely evaluated to inform breeding decisions. In this study, we used alpha lattice design to assess the phenotypic variability of 180 fonio accessions using 20 agro morphological descriptors, including both qualitative and quantitative traits at Bengou research station in 2018 and 2019. Descriptive statistics, combined analysis and multivariate analyses, including principal components analysis (PCA), hierarchical clustering, and multiple factor analysis (MFA) were performed. As results, we found significant differences among fonio accessions and among agro ecological zones of provenance for most of the quantitative traits. Furthermore, highly significant positive correlations were found between grain yield and other yield-related attributes such as harvest index and thousand seeds weight, whereas significant negative correlations were found between grain yield and flowering and maturity times. Clusters analysis revealed three phenotypic groups. Group 1 was characterized by early maturing fonio accessions with higher grain yield. Groups 2 and 3 were characterized by late maturing accessions with intermediate to moderate grain yield. The accessions from Group 1 are candidate for yield improvement and development of fonio lines with enhanced lodging resistance. Accessions from Group 2 and 3 can be improved for yield through marker-assisted selection of best thousand seed weight. This study highlights how traits are correlated within the major phenotypic groups of fonio in West Africa, and we discussed how these groups could be further exploited for improving traits of economic importance. Furthermore, this study exhibited agro morphological descriptors that discriminate fonio accessions and provide useful information for parental selection with economically important agronomic traits.
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Burr, Tom, Ian Schwerdt, Kari Sentz, Luther McDonald et Marianne Wilkerson. « Overview of Algorithms for Using Particle Morphology in Pre-Detonation Nuclear Forensics ». Algorithms 14, no 12 (24 novembre 2021) : 340. http://dx.doi.org/10.3390/a14120340.
Texte intégralRésumé :
A major goal in pre-detonation nuclear forensics is to infer the processing conditions and/or facility type that produced radiological material. This review paper focuses on analyses of particle size, shape, texture (“morphology”) signatures that could provide information on the provenance of interdicted materials. For example, uranium ore concentrates (UOC or yellowcake) include ammonium diuranate (ADU), ammonium uranyl carbonate (AUC), sodium diuranate (SDU), magnesium diuranate (MDU), and others, each prepared using different salts to precipitate U from solution. Once precipitated, UOCs are often dried and calcined to remove adsorbed water. The products can be allowed to react further, forming uranium oxides UO3, U3O8, or UO2 powders, whose surface morphology can be indicative of precipitation and/or calcination conditions used in their production. This review paper describes statistical issues and approaches in using quantitative analyses of measurements such as particle size and shape to infer production conditions. Statistical topics include multivariate t tests (Hotelling’s T2), design of experiments, and several machine learning (ML) options including decision trees, learning vector quantization neural networks, mixture discriminant analysis, and approximate Bayesian computation (ABC). ABC is emphasized as an attractive option to include the effects of model uncertainty in the selected and fitted forward model used for inferring processing conditions.
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Braun, Henry. « Data in the Educational and Social Sciences : It’s Time for Some Respect ». International Journal of Educational Methodology 7, no 3 (15 août 2021) : 447–63. http://dx.doi.org/10.12973/ijem.7.3.447.
Texte intégralRésumé :
<p style="text-align: justify;">This article introduces the concept of the carrying capacity of data (CCD), defined as an integrated, evaluative judgment of the credibility of specific data-based inferences, informed by quantitative and qualitative analyses, leavened by experience. The sequential process of evaluating the CCD is represented schematically by a framework that can guide data analysis and statistical inference, as well as pedagogy. Aspects of each phase are illustrated with examples. A key initial activity in empirical work is data scrutiny, comprising consideration of data provenance and characteristics, as well as data limitations in light of the context and purpose of the study. Relevant auxiliary information can contribute to evaluating the CCD, as can sensitivity analyses conducted at the modeling stage. It is argued that early courses in statistical methods, and the textbooks they rely on, typically give little emphasis to, or omit entirely, discussion of the importance of data scrutiny in scientific research. This inattention and lack of guided, practical experience leaves students unprepared for the real world of empirical studies. Instructors should both cultivate in their students a true respect for data and engage them in authentic empirical research involving real data, rather than the context-free data to which they are usually exposed.</p>
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Donner, R., et A. Witt. « Characterisation of long-term climate change by dimension estimates of multivariate palaeoclimatic proxy data ». Nonlinear Processes in Geophysics 13, no 5 (21 septembre 2006) : 485–97. http://dx.doi.org/10.5194/npg-13-485-2006.
Texte intégralRésumé :
Abstract. The problem of extracting climatically relevant information from multivariate geological records is tackled by characterising the eigenvalues of the temporarily varying correlation matrix. From these eigenvalues, a quantitative measure, the linear variance decay (LVD) dimension density, is derived. The LVD dimension density is shown to serve as a suitable estimate of the fractal dimension density. Its performance is evaluated by testing it for (i) systems with independent components and for (ii) subsystems of spatially extended linearly correlated systems. The LVD dimension density is applied to characterise two geological records which contain information about climate variability during the Oligocene and Miocene. These records consist of (a) abundances of different chemical trace elements and (b) grain-size distributions obtained from sediment cores offshore the East Antarctic coast. The presented analysis provides evidence that the major climate change associated with the Oligocene-Miocene transition is reflected in significant changes of the LVD dimension density. This is interpreted as a change of the interrelationships between different trace elements in the sediment and to a change of the provenance area of the deposited sediment.