Relevant bibliographies by topics / Sr and Nd isotopic compositions

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Academic literature on the topic 'Sr and Nd isotopic compositions'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Sr and Nd isotopic compositions"

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Palacz, Z. A., and S. R. Tait. "Isotopic and geochemical investigation of unit 10 from the Eastern Layered Series of the Rhum Intrusion, Northwest Scotland." Geological Magazine 122, no. 5 (1985): 485–90. http://dx.doi.org/10.1017/s0016756800035408.

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AbstractSr and Nd isotopic compositions together with whole rock Sr and Nd abundances and olivine compositions are presented for cumulates from unit 10 of the Eastern Layered Series of the Rhum intrusion, Northwest Scotland.The results show an Nd–Sr isotopic correlation consistent with contamination by high 87Sr/86Sr, low 143Nd/144Nd crust. There is a strong correlation between the degree of contamination, Sr and Nd whole rock abundance and Fe enrichment in cumulus olivine. The allivalites are the most contaminated, while the basal peridotites are uncontaminated. This suggests that the cumulates crystallized from a primitive uncontaminated magma and the allivalites from an evolved contaminated magma. Subsequently, movement of contaminated feldspathic intercumulus liquid has perturbed the isotopic, trace element and olivine composition of the upper peridotites.
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YOSHIKAWA, Masako. "Sr-Nd isotopic compositions of oceanic mantle." Japanese Magazine of Mineralogical and Petrological Sciences 42, no. 6 (2013): 247–57. http://dx.doi.org/10.2465/gkk.120608a.

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Dempsey, C. S., A. N. Halliday, and I. G. Meighan. "Combined Sm-Nd and Rb-Sr isotope systematics in the Donegal granitoids and their petrogenetic implications." Geological Magazine 127, no. 1 (1990): 75–80. http://dx.doi.org/10.1017/s0016756800014175.

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AbstractThe metaluminous to peraluminous granitoids of the Donegal batholith, northwest Ireland, were emplaced at c. 400 Ma into greenschist-amphibolite facies metasediments of the Dalradian Supergroup. Sm-Nd and Rb-Sr isotopic data are provided for eleven granitoid samples from six of the plutons and one specimen from the northeast granodiorite pluton of the Newry complex, Co. Down; the Donegal results reveal essentially similar initial Sr isotope ratios (0.7051–0.7068) but highly variable initial eNd values, −1.2 to −8.3 (and −0.5 for Newry). Certain granitoids have distinctive Nd isotopic compositions characteristic of the involvement of old, LREE-enriched continental crust in some cases or young crust and/or mantle-derived magmas in others. The Nd and Sr isotopic variations can be explained by a variety of mixing hypotheses.
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Roulleau, Emilie, and Ross Stevenson. "Geochemical and isotopic (Nd–Sr–Hf–Pb) evidence for a lithospheric mantle source in the formation of the alkaline Monteregian Province (Quebec)." Canadian Journal of Earth Sciences 50, no. 6 (2013): 650–66. http://dx.doi.org/10.1139/cjes-2012-0145.

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We present new major element and isotopic (Nd–Sr–Hf–Pb) data and modelling from alkaline rocks of the Monteregian Igneous Province of southern Quebec (Canada) that constrain the mantle source and the magmatic origin of these rocks. The whole-rock chemical composition of the intrusions is consistent with fractional crystallization of an assemblage of olivine ± clinopyroxene (± plagioclase) derived from ocean island basalts (OIB)-like magmas, and variations in the Sr and Nd isotope compositions suggest as much as 20% crustal contamination. The bulk of the Nd–Sr–Hf and Pb isotopic data form a tight cluster between a depleted mantle end-member (HIMU, high-U/Pb mantle) and an enriched mantle (EMI) end-member and are thought to reflect a sub-continental lithospheric mantle that was metasomatized by a convecting asthenospheric plume. Variations in these isotopic compositions along the west–east axis of the Monteregian Province (from the Oka carbonatite to the Mount Shefford intrusion) may reflect various degrees of mixing between HIMU and EMI enriched mantle reservoirs. Anomalously low 207Pb/204Pb and 208Pb/204Pb isotopic ratios from some of the intrusions likely indicate incorporation of an Archean component within the lithospheric mantle. We propose a model in which Monteregian magmatism formed from melting of a predominantly Proterozoic metasomatized lithospheric mantle in response to lithospheric extension during the opening of the North Atlantic Ocean at ca. 124 Ma.
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Hindshaw, Ruth S., Nicholas J. Tosca, Alexander M. Piotrowski, and Edward T. Tipper. "Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard)." Earth Surface Dynamics 6, no. 1 (2018): 141–61. http://dx.doi.org/10.5194/esurf-6-141-2018.

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Abstract. The identification of sediment sources to the ocean is a prerequisite to using marine sediment cores to extract information on past climate and ocean circulation. Sr and Nd isotopes are classical tools with which to trace source provenance. Despite considerable interest in the Arctic Ocean, the circum-Arctic source regions are poorly characterised in terms of their Sr and Nd isotopic compositions. In this study we present Sr and Nd isotope data from the Paleogene Central Basin sediments of Svalbard, including the first published data of stream suspended sediments from Svalbard. The stream suspended sediments exhibit considerable isotopic variation (εNd = −20.6 to −13.4; 87Sr ∕ 86Sr = 0.73421 to 0.74704) which can be related to the depositional history of the sedimentary formations from which they are derived. In combination with analysis of the clay mineralogy of catchment rocks and sediments, we suggest that the Central Basin sedimentary rocks were derived from two sources. One source is Proterozoic sediments derived from Greenlandic basement rocks which are rich in illite and have high 87Sr ∕ 86Sr and low εNd values. The second source is Carboniferous to Jurassic sediments derived from Siberian basalts which are rich in smectite and have low 87Sr ∕ 86Sr and high εNd values. Due to a change in depositional conditions throughout the Paleogene (from deep sea to continental) the relative proportions of these two sources vary in the Central Basin formations. The modern stream suspended sediment isotopic composition is then controlled by modern processes, in particular glaciation, which determines the present-day exposure of the formations and therefore the relative contribution of each formation to the stream suspended sediment load. This study demonstrates that the Nd isotopic composition of stream suspended sediments exhibits seasonal variation, which likely mirrors longer-term hydrological changes, with implications for source provenance studies based on fixed end-members through time.
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Nedosekova, I. L., V. A. Koroteev, T. B. Bayanova, P. A. Serov, V. I. Popova, and M. V. Chervyakovskaya. "On the age of pyrochlore carbonatites from the Ilmeno-Vishnevogorsky Alkaline Complex, the Southern Urals (insights from Rb-Sr and Sm-Nd isotopic data)." LITHOSPHERE (Russia) 20, no. 4 (2020): 486–98. http://dx.doi.org/10.24930/1681-9004-2020-20-4-486-498.

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Research subject. In this research, we carried out Sm-Nd- и Rb-Sr-dating of pyrochlore carbonatite from the Vishnevogorsky niobium deposit, Ilmeno-Vishnevogorsky Alkaline Complex, Southern Urals. IVC is located in the Ural fold region and is a carbonatite complex of the linear type. Rare metal (Nb-Zr-TR) deposits and occurrences are related to IVC. The age and the duration of IVC deposits formation remains a matter of debate. To determine the age of IVC carbonatites and related niobium ore, we measured Sm-Nd and Rb-Sr isotopic compositions and concentrations of the elements in the minerals (pyrochlore, calcite, apatite, biotite) and bulk sample of pyrochlore carbonatite. Materials and methods. The Sm and Nd isotopic compositions and concentrations were determined on a Finnigan MAT-262L (RPQ) seven-collector mass spectrometer in the static regime at the Geological Institute of the Kola Scientific Center, Apatity, Russia. The Sr and Rb isotopic compositions and concentrations were determined on thermos-ionization mass spectrometer Triton Plus (“Geoanalitik”, IGG UD RAN, Ekaterinburg, Russia). Results. Age of pyrochlore carbonatites from ore zone 140 (Vishnevogorsky deposit, IVC) defined by Sm-Nd and Rb-Sr isotopic methods. Mineral Sm-Nd-isochron (5 points) indicated age 229 ± 16 Ma, mineral Rb-Sr-isochron (5 points) showed similar age 250.5 ± 1.2 Ma. Conclusions. Results Sm-Nd и Rb-Sr dating indicate that the pyrochlore сarbonatites of ore zone 140 crystallized ≈ 250 Ma ago, at the stage of the postcollisional extension, possibly, in connection with exhumation complex, which was accompanied by decompression, partial melting of rocks, involving fluids, dissolution and precipitation of Ordovician-Silurian alkaline-carbonatitе complex. Thus, the formation of the IVC carbonatites and related Nb-ore, which began in Silurian (S), continued in Permian (P) and Triassic (T1-2) and was associated with the post-collision stage of tectonic activity in the Ural Fold Belt.
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Chen, Shuang-Shuang, Tong Hou, Jia-Qi Liu, and Zhao-Chong Zhang. "Geochemical Variation of Miocene Basalts within Shikoku Basin: Magma Source Compositions and Geodynamic Implications." Minerals 11, no. 1 (2020): 25. http://dx.doi.org/10.3390/min11010025.

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Shikoku Basin is unique as being located within a trench-ridge-trench triple junction. Here, we report mineral compositions, major, trace-element, and Sr-Nd-Pb isotopic compositions of bulk-rocks from Sites C0012 (>18.9 Ma) and 1173 (13–15 Ma) of the Shikoku Basin. Samples from Sites C0012 and 1173 are tholeiitic in composition and display relative depletion in light rare earth elements (REEs) and enrichment in heavy REEs, generally similar to normal mid-ocean ridge basalts (N-MORB). Specifically, Site C0012 samples display more pronounced positive anomalies in Rb, Ba, K, Pb and Sr, and negative anomalies in Th, U, Nb, and Ta, as well as negative Nb relative to La and Th. Site 1173 basalts have relatively uniform Sr-Nd-Pb isotopic compositions, close to the end member of depleted mantle, while Site C0012 samples show slightly enriched Sr-Nd-Pb isotopic signature, indicating a possible involvement of enriched mantle 1 (EM1) and EM2 sources, which could be attributed to the metasomatism of the fluids released from the dehydrated subduction slab, but with the little involvement of subducted slab-derived sedimentary component. Additionally, the Shikoku Basin record the formation of the back-arc basin was a mantle conversion process from an island arc to a typical MORB. The formation of the Shikoku Basin is different from that of the adjacent Japan Sea and Parece Vela Basin, mainly in terms of the metasomatized subduction-related components, the nature of mantle source, and partial melting processes.
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DU, ZHIHENG, CUNDE XIAO, MINGHU DING, and CHUANJIN LI. "Identification of multiple natural and anthropogenic sources of dust in snow from Zhongshan Station to Dome A, East Antarctica." Journal of Glaciology 64, no. 248 (2018): 855–65. http://dx.doi.org/10.1017/jog.2018.72.

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ABSTRACTThe stable oxygen isotope composition, major ions and isotopic compositions of strontium (Sr), neodymium (Nd) and lead (Pb) in insoluble dust from recent surface snow samples along the transect from the Zhongshan and Progress stations (located on the Amery Ice Shelf, East Antarctica) to Dome A (Summit, Antarctica) were analysed. No previous isotopic fingerprinting studies have been conducted for this transect. These data were used to document the dust provenances in Antarctica along the transect up to the highest site, Dome A, for the first time. The insoluble dust in snow samples along the coast displays an overall crust-line isotopic signature that is characterised by highly radiogenic 87Sr/86Sr values and less radiogenic 143Nd/144Nd values. These signatures are comparable with those of samples collected near the ice-free areas of the Zhongshan and Progress stations. Spatial differences are statistically significant along the transect, and the Sr, Nd and Pb isotope components in insoluble dust from two continuous snow samples at Dome A exhibit marked differences, indicating that additional dust reaches the East Antarctic Plateau. The isotopic characteristics of insoluble dust from this transect indicate that the long-distance natural dust and anthropogenic pollutants in these samples primarily originate from Australia.
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XIONG, LE, JUNHAO WEI, WENJIE SHI, et al. "Geochronology, petrology and geochemistry of the Mesozoic Dashizhuzi granites and lamprophyre dykes in eastern Hebei – western Liaoning: implications for lithospheric evolution beneath the North China Craton." Geological Magazine 155, no. 7 (2017): 1542–65. http://dx.doi.org/10.1017/s0016756817000437.

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AbstractGeochronological, elemental and isotopic data of the Dashizhuzi granites and lamprophyre dykes from the eastern Hebei – western Liaoning on the northern North China Craton (NCC) provide an insight into the nature of their magma sources and subcontinental lithospheric mantle. The Dashizhuzi granites have an emplacement age of 226 Ma. They have enriched lithospheric mantle type 1 (EM1-like) Sr–Nd isotopic compositions, and have distinctive features of high Na2O and Sr and low Y with high Sr/Y and (La/Yb)N ratios. These characteristics show that the Dashizhuzi granites originated directly from melting of mafic lower crust composed of pre-existing ancient crustal and enriched mantle-derived juvenile crustal materials at normal continental crustal depth of 33–40 km. The lamprophyre dykes are dated at 167 Ma, and can be divided into two groups. The Group 1 dykes have variable Sr–Nd isotopic compositions and mid-ocean-ridge basalt (MORB-) like Th/U, Ba/Th and Ce/Pb ratios, whereas the Group 2 dykes have enriched Sr–Nd isotopic compositions and notable high Co, Cr, MgO and low Al2O3 characteristics. These distinctive features suggest that the Group 1 dykes were derived from a relatively fertile lithospheric mantle source (garnet-facies amphibole-bearing lherzolite) which has experienced variable degrees of asthenospheric mantle-derived melt–peridotite interaction prior to melting. However, the Group 2 dykes were derived from an ancient garnet-facies phlogopite and/or amphibole-bearing lherzolite lithospheric mantle. Thinning of the Early Mesozoic lithospheric mantle beneath the northern NCC is dominantly through melt–peridotite interaction and thermo-mechanical erosion prior to Middle Jurassic time. The chemical compositions have been modified at the bottom of the lithospheric mantle through melt–peridotite interaction processes.
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Giuliani, Andrea, Matthew G. Jackson, Angus Fitzpayne, and Hayden Dalton. "Remnants of early Earth differentiation in the deepest mantle-derived lavas." Proceedings of the National Academy of Sciences 118, no. 1 (2020): e2015211118. http://dx.doi.org/10.1073/pnas.2015211118.

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The noble gas isotope systematics of ocean island basalts suggest the existence of primordial mantle signatures in the deep mantle. Yet, the isotopic compositions of lithophile elements (Sr, Nd, Hf) in these lavas require derivation from a mantle source that is geochemically depleted by melt extraction rather than primitive. Here, this apparent contradiction is resolved by employing a compilation of the Sr, Nd, and Hf isotope composition of kimberlites—volcanic rocks that originate at great depth beneath continents. This compilation includes kimberlites as old as 2.06 billion years and shows that kimberlites do not derive from a primitive mantle source but sample the same geochemically depleted component (where geochemical depletion refers to ancient melt extraction) common to most oceanic island basalts, previously called PREMA (prevalent mantle) or FOZO (focal zone). Extrapolation of the Nd and Hf isotopic compositions of the kimberlite source to the age of Earth formation yields a143Nd/144Nd-176Hf/177Hf composition within error of chondrite meteorites, which include the likely parent bodies of Earth. This supports a hypothesis where the source of kimberlites and ocean island basalts contains a long-lived component that formed by melt extraction from a domain with chondritic143Nd/144Nd and176Hf/177Hf shortly after Earth accretion. The geographic distribution of kimberlites containing the PREMA component suggests that these remnants of early Earth differentiation are located in large seismically anomalous regions corresponding to thermochemical piles above the core–mantle boundary. PREMA could have been stored in these structures for most of Earth’s history, partially shielded from convective homogenization.
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Dissertations / Theses on the topic "Sr and Nd isotopic compositions"

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WAKAKI, Shigeyuki. "Estimation of optimal isotopic compositions of Sr, Ba, Nd and Sm spikes for double spike thermal ionization mass spectrometry by error propagation simulation." Dept. of Earth and Planetary Sciences, Nagoya University, 2012. http://hdl.handle.net/2237/20538.

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Schmidberger, Stefanie. "Hf, Sr, Nd and Pb isotope systematics and major and trace element compositions of the Archean subcratonic lithosphere beneath Somerset Island, Arctic Canada." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37656.

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Hf, Sr, Nd and Pb isotopes, and major, trace and rare earth elements (REE) were determined for a suite of peridotite and pyroxenite xenoliths, constituent garnet and clinopyroxene and the host Nikos kimberlite (100 Ma) from Somerset Island, in order to constrain the chemical and isotopic composition of the lithosphere beneath the northern Canadian craton. The refractory Nikos peridotites are characterized by high olivine forsterite contents (avg. Fo = 92.3) and depletions in incompatible major elements (Fe, Al, Ca), but are enriched in incompatible trace elements, such as large ion lithophile elements (LILE) and light rare earth elements (LREE), while having approximately chondritic heavy rare earth element (HREE) contents. Mass balance calculations using REE contents of clinopyroxene and garnet indicate that calculated LREE abundances for the Nikos xenoliths are significantly lower (e.g. Nd ~50%) than those of the analyzed whole-rocks. These results suggest the presence of small amounts of a kimberlite-related LREE-rich interstitial component (i.e. ~1% kimberlite liquid and/or ~0.01% apatite) to account for the excess LREE abundances, with little effect on the HREE budgets of the xenoliths.<br>The 143Nd/144Nd(0.1Ga) (0.51249--0.51276) isotopic compositions of the Nikos peridotites are little variable and overlap those of the Nikos kimberlite at the time of sample transport. The low-temperature peridotites (<1100°C) that sample the shallow lithosphere are characterized by more radiogenic 176Hf/177Hf(0.1Ga) (0.28296--0.28419) and Pb (206Pb/204Pb (0.1Ga) = 17.82--19.03), but lower 87Sr/ 86Sr(0.1Ga) (0.7047--0.7066) isotopic ratios than those of the high-temperature peridotites (>1100°C; 0.28265--0.28333; 17.18--18.30; 0.7064--0.7085, respectively). Incompatible trace element compositions of the xenoliths confirm this depth stratification indicating that shallow and deep (>160 km) Somerset lithosphere are characterized by distinct chemical and isotopic characteristics.<br>The Lu-Hf isotope compositions of the low-temperature peridotites plot along a 2.8 Ga reference isochron, which is consistent with an interpretation that the shallow Somerset lithosphere stabilized in the Archean to depth of ~150 km. The deep lithospheric mantle, which is probably younger, does not share the same petrogenetic history and may contain recycled material (altered oceanic crust and sedimentary component?). The Hf isotope compositions for the shallow low-temperature peridotites indicate that part of the lithosphere beneath the Canadian craton is characterized by more radiogenic Hf isotope signatures than estimates for "depleted" mantle.
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Sumino, Hirochika, Takamasa Hayashi, Toshio Nakamura, et al. "Radiometric ages and Nd-Sr isotopic compositions of felsic plutonic rocks from the Ulleungdo volcanic island, South Korea(Proceedings of the 19^ Symposium on Chronological Studies at the Nagoya University Center for Chronological Research in 2006,Part1)." 名古屋大学年代測定資料研究センター, 2007. http://hdl.handle.net/2237/13673.

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第19回名古屋大学年代測定総合研究センターシンポジウム平成18(2006)年度報告<第1部> Proceedings of the 19th symposiumon on Chronological Studies at the Nagoya University Center for Chronological Research in 2006 日時:平成19 (2007)年1月15日(月)～17日(水) 会場:名古屋大学シンポジオン Date:January15th-17th, 2007 Venue:Nagoya Uhiversity Symposion Hall
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Joussain, Ronan. "Histoire de l’érosion de l’Himalaya durant le dernier cycle climatique : approches sédimentologiques, minéralogiques et géochimiques des sédiments de la partie proximale de l’éventail sous-marin profond du Bengale." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS433.

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L’objectif de cette étude est de reconstruire le régime de l’érosion des chaînes himalayennes, et de relier ces paramètres aux variations climatiques globales et à l’intensité de la mousson. Dans ce travail, Les sédiments de 3 carottes prélevées dans la baie du Bengale pendant la mission MONOPOL ont fait l’objet d’analyses minéralogiques (XRD et granulométrie) et géochimiques (majeurs, traces, la composition isotopique du Nd et du Sr). La mise en âge des carottes, est basée sur les enregistrements de δ¹⁸O de foraminifères planctoniques (G. ruber), et des datations au ¹⁴C (AMS). Ces 3 enregistrements sédimentaires couvrent les derniers 180 ka. L'approche multi-traceur menée sur ces carottes, nous donne des informations essentielles sur les sources, afin de reconstruire les changements au cours du temps des sédiments transportés vers la partie proximale du cône sous-marin du Bengale, et de mieux comprendre ses liens potentiels avec les changements climatiques (mousson indienne et/ou des changements au niveau de la mer). Les résultats de cette étude, donnent également des clefs sur les processus d'altération chimique et de la dynamique du transport des sédiments au cours du temps. En outre, une étude à haute résolution, sur un site localisé sur la levée du chenal actif du cône sous-marin fournit des informations sur les changements dans le degré d'altération et la dynamique de transport des sédiments du système himalayen au cours de l'Holocène. Ainsi, il est possible de quantifier l'impact de la mousson d’été sur la sédimentation au niveau de la levée durant cette période climatique. Les résultats de cette étude ont été utilisés pour estimer les changements dans les sources sédimentaires (plaine Indo-Gangétique vs haute-chaine) et retracer l'altération chimique du matériel détritique au sein du bassin versant du système fluviatile du Ganges-Brahmapoutre<br>The aim of this study is to reconstruct the erosional history of the Himalayan ranges, in order to connect these parameters to global climatic events and variations in the intensity of the monsoon. In this work, sediments from 3 marine cores collected in the Bay of Bengal, during the MONOPOL cruise were analyzed using mineralogical (XRD and grain-size) and geochemical (major, trace, Nd and Sr isotopic composition) methods. Chronological framework of studied cores were based on δ¹⁸O from planktonic foraminifera (G. ruber), and ¹⁴C ages dating (AMS). These cores cover the last 180 kyr. The multi-proxy approach conducted on these cores, gives us critical information about the source, to reconstruct the temporal variability of sediment export to the proximal northeastern Bengal Fan and its potential links to climatic changes (Indian monsoon and/or sea-level changes). Results also give insights on the chemical weathering processes and the dynamic of transport of the sediments through time as well. Moreover, a high-resolution study, on a site located on the active middle fan channel levee of the fan provides information on changes in the weathering pattern and the dynamic of transport of sediments from the Himalayan system during the Holocene. Thus, it is possible to quantify the impact effect of summer monsoon rainfall during that time interval. These results have been used to assess changes in the sedimentary sources (Indo-Gangetic plain vs highlands) and document the chemical weathering states of the detrital material within the Ganges-Brahmaputra river basin catchment
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Mahanjane, Laura Nilza Mendes. "Estudos petrográficos e geocronológicos do prospecto Mankombiti, Cinturão de Fíngoè, Província de Tete, noroeste de Moçambique." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-03062015-092751/.

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O cinturão Fíngoè é uma unidade tectônica do Supercontinente Gondwana Oeste composta por rochas supracrustais formadas há aproximadamente 1.33 Ga. Essas rochas são portadoras de mineralizações de Au, Cu, Zn, Pb e Fe. Com cerca de 150 km de comprimento, e orientado WSW-ENE, este cinturão estende-se desde o Monte Atchiza a oeste até cerca de 30 km para leste da vila de Fíngoè no norte de Moçambique e consiste de uma extensa variedade de rochas metassedimentares e metavulcânicas. O cinturão Fíngoè apresenta especialização metalogenética para Au e Cu, que já foram explotados no passado em diversos locais. Muitos destes registros estão associados com magnetita e malaquita. Atualmente trabalhos de prospecção e pesquisa mineral têm sido realizados pela empresa de mineração African Queen Mines Ltda, através do projeto denominado de King Solomons, localizado na parte central do mesmo. A geologia da área abrangida pelo prospecto Mankombiti, mostra uma predominância de rochas carbonáticas, granitos e gabros. As rochas carbonáticas são consideradas importantes na gênese de depósitos tipo skarn e depósitos de substituição de metais de base e Au devido à sua natureza fortemente reativa. Os dados geocronológicos realizados neste trabalho indicaram uma idade precisa para a rocha intrusiva granítica associada à mineralização de 1079,1 ± 8,2 Ma, que poderia ser a idade da formação do skarn e consequentemente desta mineralização. Entretanto a idade obtida para o processo de alteração hidrotermal que afetou o gabro, na ordem de 657 ± 36 Ma e a idade modelo Pb-Pb sugerida pelo modelo de Stacey e Kramers (1975) para a calcopirita da mineralização principal de 725 Ma, sugerem que a mineralização, do prospecto Mankombiti é neoproterozóica. Para melhor entendimento dos processos que estiveram envolvidos na formação deste depósito skarn, duas hipóteses são consideradas: (i) poderia ser admitida a presença de corpos graníticos intrusivos em 700 Ma, situados em profundidade, que não foram ainda caracterizados, como responsáveis pela fonte de calor necessária, (ii) pode ser admitida ocorrência de um evento distensional em 700 Ma que produziria um adelgaçamento da litosfera e a consequente ascensão da astenosfera, produzindo uma elevação do fluxo térmico gerando os fluidos mineralizantes necessários.<br>The Fíngoè belt is a tectonic unit of West Gondwana Supercontinent, comprised of supracrustal rocks formed at approximately 1.33 Ga. These rocks are carriers of Au, Cu, Zn, Pb and Fe mineralization. With about 150 km long and oriented WSW- ENE, this belt extends from west of the Atchiza Mount to about 30 km east of the Fíngoè village in the north Mozambique, and consists of an extensive variety of metasedimentary and metavolcanic rocks. The Fíngoè metallogenic belt provides specialization for Au and Cu, which have been exploited in the past in various locations. Many of these records are associated with magnetite and malachite. Currently, the prospecting and mineral exploration have been conducted by the African Queen Mines Ltd mining company, through a project called the King Solomons, located in the central part of it. The geology of the studied area shows a predominance of carbonate rocks, granites and gabbros. The carbonate rocks are considered important in the genesis of the skarn deposits type and deposits of replacement for base metals and Au due to its highly reactive nature. The geochronological data performed in this work indicate a precise age of the 1079.1 ± 8.2 Ma for the intrusive granitic rock associated with mineralization, which could be interpreted as the age of the skarn and consequently of the mineralization. However the age obtained for the hydrothermal alteration that affected the gabbro at about 657 ± 36 Ma and the Pb-Pb model age suggested by the model of Stacey and Kramers (1975) for primary chalcopyrite mineralization at 725 Ma, suggesting that the mineralization of the Mankombiti prospectus was developed during the Neoproterozoic time. For understanding the processes that were involved in the skarn-type mineralization processes, two hypotheses are here considered: (i) could be admitted the presence of i ntrusive granitic rocks at 700 Ma, situated in depth, which have not yet been characterized, as responsible for the heat source required, (ii) may be admitted occurrence of an extensional event at 700 Ma to produce a thinning of the lithosphere and the uplift of the asthenosphere, producing high thermal flows generating the mineralization fluids.
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David, Marta Edith Velásquez. "Composição isotópica de Pb-Sr e Nd da mineralização de ouro do depósito Córrego do Sítio, Quadrilátero Ferrífero (MG): implicações na modelagem conceitual." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-19042007-142433/.

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O Quadrilátero Ferrífero (MG) é uma importante unidade geotectônica do Cráton do São Francisco que alberga jazidas de ferro e ouro hospedadas na seqüência greenstone belt Rio das Velhas e cuja evolução geodinâmica esteve regida por vários eventos tectonometamórficos. Depósitos de ouro gerados por fluidos epitermais e remobilizações orogênicas proterozóicas se associam intimamente com camadas bandas de ferro e raramente disseminados em metapelitos no topo do greenstone. Nas mineralizações é comum uma paragênese que cristalizou mediante diversos processos e em distintos estágios com predomínio de sulfetos de ferro. Em geral os minérios possuem forte controle estrutural por dobras, falhas e cisalhamentos transcorrentes, desenvolvidos durante vários eventos deformacionais de diversa índole e estreita relação com processos de alteração hidrotermal como sericitização, carbonatação, cloritização, entre outros de menor incidência. O depósito de ouro Córrego do Sítio hospeda-se na seqüência silisiclástica de origem turbidítica metamorfisada em fácies xisto verde denominada Associação de Litofácies Ressedimentada que faz parte do Grupo Nova Lima, se apresenta disseminado em metapelitos e em veios de quartzo com carbonato. A mineralização que acompanha o ouro cristalizou em vários estágios principais nos que predominaram (i) pirita + pirrotita, (ii) arsenopirita + pirrotita + pirita com texturas finas e orientadas, (iii) arsenopirita com pirrotita e sulfosais em veios de quartzo, (iv) pirita grossa pervasiva em todas as rochas hospedeiras. O estudo da composição isotópica Pb, Sr e Nd, permitiu identificar que as fontes dos fluidos mineralizantes foram as rochas hospedeiras, que na evolução policíclica da mineralização participaram eventos metamórficos e hidrotermais a 2.2, 2.0 Ga. e sobreimpostos a ~600 Ma. os quais induziram os processos de circulação hidrotermal na área de estudo. Mediante comparativa com outros depósitos da região, sugere-se que os metais formadores do minério depositaram-se em Córrego do Sítio à idade de 2.2 Ga. originados a partir da BIF tipo São Bento e remobilizados por fluidos através de falhas inversas. Análises geocronológicas U-Pb (SHRIMP) e K-Ar embora não decisivos em quanto à determinação da idade da mineralização, revelaram a idade de ~2.7 Ga. como o limite temporal para a deposição das rochas hospedeiras. No contexto geológico aplicado se estabelece a potencialidade para a prospecção aurífera que apresentam as rochas metapelíticas do topo do Greenstone Belt Rio das Velas associadas a camadas bandadas de ferro com ouro, e que os alvos mais relevantes seriam zonas com falhas inversas e cisalhamentos transcorrentes.<br>The Quadrilátero Ferrífero is an important geotectonic unit of the São Francisco Craton that host iron and gold deposits within the vulcanosedimentary rocks of the greenstone belt Rio das Velhas. The geodynamic evolution of this greenstone includes several tectonometamorphic events. Gold deposits were formed by epithermal fluids, remobilized during the Proterozoic orogenic processes, are associated whit the banded iron formations and are sporadically disseminate in metapelitic rocks within the top of the greenstone sequence. In the ores is common the crystallization of iron sulfide minerals during diverse stages. Gold deposits have an important structural control by folds, reverse faults and strike-slip shearing zones, and are commons several hydrothermal alteration processes like sericitization, chloritization and carbonate usually related to the deformation. The Córrego do Sítio gold deposit is hosted in turbiditic siliciclastic rocks that are metamorphosed in the greenschist facies. The gold is associated with the iron sulfide arsenopyrite and pyrite, which are disseminated in metapelitic rocks and quartz-carbonate veins. The mineralization includes vary stages of crystallization, (1) pyrite and pyrrotite (2) arsenopyrite, pyrrotite and fine pyrite, (3) arsenopyrite whit pyrrotite and sulphosalts in quartz vein, and (4) pervasive pyrite. An integrated Pb, Sr e Nd, isotopic study of the Córrego do Sítio deposit allowed to identify that sources of the mineralizing fluids was the host rocks, that in the policiclic evolution the gold mineralizaton had participation events of metamorphism and hidrothermalism to age 2.2, 2.0 and 0.6 Ga. respectively the wich induced the hydrothermal circulation processes in the study area. The isotopic character of this deposit and its comparison with similar ones, suggest that the gold and its metals associated it is deposited in Córrego do Sítio to age 2.2 Ga. and that metals were derived from the banded iron formations, and remobilized by hidrothermal fluids across reverse faults. Although U-Pb (SHRIMP) and K-Ar geochronologic data were not conclusive to constrain the age of the mineralization, they provide to age ~2.7 Ga. that a good limit for the sedimentation of the host rock. It is suggest that there is a potential for gold prospection within the metapellitic rocks associated with banded iron formation of the Greenstone Rio das Velhas, and that the more relevant targets include areas with inverse and strike-slip fault.
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Anglin, Carolyn Diane Carleton University Dissertation Geology. "Sm-Nd and Sr isotopic studies of scheelite from some Superior Province gold deposits." Ottawa, 1992.

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Handley, Heather K. "Geochemical and Sr-Nd-Hf-O isotopic constraints on volcanic petrogenesis at the Sunda Arc, Indonesia." Thesis, Durham University, 2006. http://etheses.dur.ac.uk/2670/.

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The Sunda island arc of Indonesia formed as a result of the northward subduction of the Indo- Australian Plate beneath the Eurasian Plate. Along-arc variations in the composition and thickness of the overriding Eurasian plate and variation in the type and amount of sediment deposited on the subducting plate create differential effects on Sunda arc lava geochemistry. Detailed study of volcanic rocks from Salak, Gede Volcanic Complex (GVC) in West Java and Ijen Volcanic Complex (IVC) in East Java was carried out in order to establish the relative importance and contributions of various potential source components and composition-modifying processes at individual volcanic centres, prior to investigating petrogenetic variation along the arc. Differentiation processes play a major role in modifying the geochemical composition of Sunda arc magmas. However, the relative importance and traceable impact of the different processes varies at each volcanic centre. Fractional crystallisation of a typical Javan island arc mineral assemblage exerts the largest control on major and trace element composition of the volcanic rocks. Distinct intra-volcanic complex differentiation trends at rvc and Salak are spatially controlled and are explained by independent conduits and multiple magma reservoirs at different depths in the crust - linked to sub-volcanic structure. Shallow level contamination by typical upper-crustal continental material is insignificant during magmatic differentiation at Salak, GVC and IVC. However, at Salak there is some evidence for assimilation of material similar in composition to the volcanic rocks. Deep fractionation of a phase in which HFSE and HREE are compatible (e.g. amphibole) is inferred in the evolution of most Javan magmas. Magmatism at Salak, GVC and IVC is the product of shallow, relatively homogeneous, fertile, Indian Ocean MORB-like mantle that has been enriched by slab- derived component(s) sourced from the altered oceanic crust and subducted sediment. Hf and Nd isotope ratios of Javan lavas show that the subducted sedimentary source component is heterogeneous and reflects spatial variations in sediment compositions on the down-going plate along the Java Trench. A progressive eastward increase in Sr isotope ratio of volcanic rocks across West and Central Java broadly correlates with inferred lithospheric thickness. A significant change in crustal architecture (i.e. thickness) occurs between Central and East Java. This transition may represent the south-eastern boundary of Sundaland (pre-Tertiary arc basement).
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Moragues, Quiroga Cristina. "Water mixing processes in the critical zone : evidence from trace elements and Sr-Nd-Pb-U isotopes." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAH002.

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Les fonctions hydrologiques de captage, stockage et rejet d’eau ont des signatures géochimiques dans les cours d'eau reflétant énormément celles trouvées dans les compartiments de la zone critique. Ces signatures sont fortement contrôlées par des processus bio-géophysico-chimiques produits dans l'interface régolite-plante. Jusqu'à présent, les recherches sur régolithes et processus hydrologiques sont restées largement découplées - conduisant à une utilisation généralisée de traceurs non conservateurs d'origines multiples, bloquant ainsi notre capacité à identifier les sources et les voies d'écoulement d’eau. Nous étudions ici le mélange d'eau dans la subsurface à travers un portefeuille unique de traceurs (éléments traces et isotopes O-H-Sr-Nd-Pb-U) permettant d'étudier les processus d'évolution du régolithe et le transport des solutés dans la zone critique. Nous signalons l'intérêt de cette approche pour renforcer la caractérisation des sources et voies d'écoulement d’eau<br>Catchment hydrological functions of water collection, storage and release have geochemical signatures in stream water largely mirroring those found in critical zone compartments. These signatures are strongly controlled by the different bio-geo-physico-chemical processes that occur within the regolith-plant interface. Until now, investigations into the critical zone’s regolith and hydrological processes research have largely remained uncoupled –leading to a widespread use of non-conservative tracers with multiple origins and thereby stymieing our capability for identifying water pools and flow paths. Here we study the mixing of water in the subsurface through a unique portfolio of complementary groups of tracers (trace elements O-Hand Sr-Nd-Pb-U isotopes) which enables investigating regolith evolution processes and solutes transport within the critical zone. We report the interest of this approach to strengthen water flowpaths and end-members characterization
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Le, Quilleuc Meryll. "Caractérisation élémentaire et isotopique (Sr et Nd) des dépôts d'aérosols sahariens sur la marge sénégalaise : implications pour la signature géochimique des sources." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R075.

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Les aérosols désertiques émis dans les régions arides et semi-arides constituent un élément actif du système climatique global. En effet, de par leurs propriétés optiques et leur rôle dans les processus de nucléation dans l’atmosphère, ils ont un impact sur le bilan radiatif et le cycle hydrologique. Ils ont également une influence sur les cycles biogéochimiques marins et continentaux par l’apport de micro-nutriments dans les régions où ils se déposent. Par ailleurs, les aérosols désertiques sont des indicateurs des changements paleo-environnementaux dans les archives sédimentaires. L’impact de l’aérosol minéral dans le système climatique dépend de la quantité de particules émises dans l’atmosphère, de leur distribution granulométrique et de leur composition géochimique. Ces paramètres sont cependant souvent insuffisamment quantifiés, en particulier dans la région du Sahara et du Sahel (plus importante source au monde), du fait des très nombreuses zones d’émission et de leur caractère intermittent. Les caractéristiques des retombées de l’aérosol saharien sont singulièrement mal connues ; celles-ci sont pourtant essentielles pour estimer son impact sur les cycles biogéochimiques, faire le lien avec les dépôts sédimentaires, et contraindre les modèles atmosphériques de transport. Une étude de dépôts éoliens a été réalisée sur la côte sénégalaise dans l’objectif d’améliorer nos connaissances sur la composition chimique des aérosols transportés sur la marge ouest africaine et la signature chimique des régions sources. Dans ce cadre, un capteur passif a été mis en place en 2006 à Mbour, permettant de construire une série temporelle continue de dépôts d’aérosols désertiques avec un pas d’échantillonnage d’une semaine ou moins. La composition élémentaire de la fraction silicatée inférieure à 30µm de 221 échantillons de dépôts a été déterminée (incluant une série continue de deux ans entre 2013 et 2015), ainsi que les rapports isotopiques du strontium (Sr) et du néodyme (Nd) de 63 de ces échantillons. En parallèle, une étude des sources alimentant notre site d’étude a été réalisée à l’aide de l’indice satellite IDDI et de rétrotrajectoires de masse d’air (HYSPLIT). L’étude de la série continue de dépôts 2013-2015 a révélé une grande variabilité dans la composition chimique des particules, suggérant une importante diversité géochimique des sources. Cette série temporelle a permis de mettre en évidence des changements saisonniers du flux et de la composition chimique, en lien avec les changements de provenance et de transport des particules entre la saison sèche (hiver-printemps) pendant laquelle les aérosols sont apportés par les alizés qui balayent le continent ouest-africain, et la saison humide (été) au cours de laquelle les dépôts résultent en partie du lessivage par les précipitations de particules transportées à haute altitude dans la Saharan Air Layer (SAL)<br>Mineral aerosols emitted in arid and semi-arid regions of the Earth represent an active element of the global climate system. In fact, due to their optical properties and their role in nucleation processes in the atmosphere, they have an impact on the radiative budget and the hydrological cycle. They also take part in many biogeochemical cycles in the ocean and on land through the input of micro-nutriments in regions where they are deposited. Mineral dust is also an indicator of paleo-environmental conditions changes in sedimentary archives. Mineral dust impact in the climate system depends on the amount of particles transported in the atmosphere, on their grain size distributions and on their geochemical compositions. Yet, these characteristics are often insufficiently quantified, particularly in the vast Sahara-Sahel domain (the largest source worldwide), due to the numerous emissions areas and to their intermittency. The characteristics of Saharan dust deposits are especially poorly constrained, although they are essentials to estimate the dust impact on biogeochemical cycles, to make the connection with sedimentary deposits, and to validate dust transport model outputs. A study of eolian deposits was carried out on the Senegalese coast in order to improve our knowledge of the chemical composition of mineral aerosols transported over the West African margin and of the geochemical signature of the source regions. For this purpose, a passive collector was set up in 2006 at Mbour, allowing the build up of a long continuous time series dust deposits with a sampling resolution of a week or less (down to 24h). Elemental composition (major and trace elements) of the &lt;30µm carbonate-free, silicate fraction of 221 dust deposit samples was determined (including a two-year continuous time series between March 2013 and February 2015), as well as the Sr and Nd isotopic ratios for 63 of them. Concurrently, investigations on the sources feeding our sampling site were conducted with the help of the IDDI satellite product as well as air masses backtrajectories calculated with the HYSPLIT model. The study of the 2013-2015 continuous time series of dust deposits revealed a large variability in the chemical composition of the dust, suggesting an important diversity in the geochemistry of the contributing sources. This long time series brought to light marked seasonal changes, both in the mass flux and the chemical composition, that can be linked to changes in provenance and transporting wind systems between the dry season (winter-spring) during which aerosols are transported in the trade winds that sweep across West Africa, and the wet season (summer) when dust deposit result to some degree from the scavenging by precipitations of dust transported at high altitude in the Saharan Air Layer (SAL)
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Books on the topic "Sr and Nd isotopic compositions"

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Survey, Ontario Geological. Geochronology Compilation Map For Ontario : Sheet 2: Southern Ontario: Grenville : Province and Environs : rb-sr, nd-sm, U-pb, and Other Isotopic Systems. s.n, 1986.

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Book chapters on the topic "Sr and Nd isotopic compositions"

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D'Antonio, Massimo, George R. Tilton, and Lucia Civetta. "Petrogenesis of Italian Alkaline Lavas Deduced from Pb-Sr-Nd Isotope Relationships." In Earth Processes: Reading the Isotopic Code. American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm095p0253.

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Okano, Osamu, and Mitsunobu Tatsumoto. "Petrogenesis of Ultramafic Xenoliths from Hawaii Inferred From Sr, Nd, and Pb Isotopes." In Earth Processes: Reading the Isotopic Code. American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm095p0135.

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Soroka, Elena I., Oksana B. Azovskova, Mikhail Yu Rovnushkin, et al. "Isotopic (δ13C, δ18O, Rb-Sr and Sm-Nd) Studies of Carbonates from the Vorontsovskoe Gold Deposit (Northern Urals)." In Springer Proceedings in Earth and Environmental Sciences. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-00925-0_36.

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Briqueu, L., C. Mével, and F. Boudier. "Sr, Nd and Pb Isotopic Constraints in the Genesis of a Calc-Alkaline Plutonic Suite in Oman Ophiolite Related to the Obduction Process." In Ophiolite Genesis and Evolution of the Oceanic Lithosphere. Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3358-6_26.

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Douglas, G., M. Palmer, and G. Caitcheon. "The provenance of sediments in Moreton Bay, Australia: a synthesis of major, trace element and Sr-Nd-Pb isotopic geochemistry, modelling and landscape analysis." In The Interactions between Sediments and Water. Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-3366-3_20.

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Konopelko, Dmitry L. "Chapter 3. Postcollisional intrusions of the Alai Segment of South Tien Shan." In PALEOZOIC GRANITOID MAGMATISM OF WESTERN TIEN SHAN. St. Petersburg State University, 2020. http://dx.doi.org/10.21638/11701/9785288060250.04.

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The early Permian intrusions of the Alai Segment of the South Tien Shan comprise four geochemically contrasting intrusive series, including (1) I-type and (2) shoshonitic granitoids, (3) peraluminous granitoids including S-type leucogranites and (4) alkaline rocks and carbonatites, closely associated in space and time. New geochronological data indicate that diverse magmatic series of the Alai segment formed virtually coevally in a post-collisional setting. Five U-Pb zircon rock ages in the range 287 – 281 Ma, in combination with published ages, define the main post-collisional magmatic pulse at 290 - 280, which is similar to ages of post-collisional intrusions elsewhere in the South Tien Shan. The Sr-Nd-Pb-Hf isotopic compositions of the studied intrusions are consistent with the reworking of crustal material with 1.6 – 1.1 Ga average crustal residence times indicating the formation of the Alai segment of the South Tien Shan on a continental basement with Mesoproterozoic or older crust. It is suggested that position of the Alai microcontinent between two major sutures enabled delamination of its lithospheric mantle, which triggered the diverse post-collisional magmatism as a result of interaction of ascending asthenospheric material with lithospheric mantle and various crustal protoliths.
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Reimold, Wolf Uwe, Toni Schulz, Stephan König, et al. "Genesis of the mafic granophyre of the Vredefort impact structure (South Africa): Implications of new geochemical and Se and Re-Os isotope data." In Large Meteorite Impacts and Planetary Evolution VI. Geological Society of America, 2021. http://dx.doi.org/10.1130/2021.2550(09).

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ABSTRACT This contribution is concerned with the debated origin of the impact melt rock in the central uplift of the world’s largest confirmed impact structure—Vredefort (South Africa). New major- and trace-element abundances, including those of selected highly siderophile elements (HSEs), Re-Os isotope data, as well as the first Se isotope and Se-Te elemental systematics are presented for the felsic and mafic varieties of Vredefort impact melt rock known as “Vredefort Granophyre.” In addition to the long-recognized “normal” (i.e., felsic, &amp;gt;66 wt% SiO2) granophyre variety, a more mafic (&amp;lt;66 wt% SiO2) impact melt variety from Vredefort has been discussed for several years. The hypothesis that the mafic granophyre was formed from felsic granophyre through admixture (assimilation) of a mafic country rock component that then was melted and assimilated into the superheated impact melt has been pursued here by analysis of the two granophyre varieties, of the Dominion Group lava (actually metalava), and of epidiorite mafic country rock types. Chemical compositions, including high-precision isotope dilution–derived concentrations of selected highly siderophile elements (Re, Os, Ir, Pt, Se, Te), and Re-Os and Se isotope data support this hypothesis. A first-order estimate, based on these data, suggests that some mafic granophyre may have resulted from a significant admixture (assimilation) of epidiorite to felsic granophyre. This is in accordance with the findings of an earlier investigation using conventional isotope (Sr-Nd-Pb) data. Moreover, these outcomes are in contrast to a two-stage emplacement model for Vredefort Granophyre, whereby a mafic phase of impact melt, derived by differentiation of a crater-filling impact melt sheet, would have been emplaced into earlier-deposited felsic granophyre. Instead, all chemical and isotopic evidence so far favors formation of mafic granophyre by local assimilation of mafic country rock—most likely epidiorite—by a single intrusive impact melt phase, which is represented by the regionally homogeneous felsic granophyre.
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Linn, A. M., and D. J. DePaolo. "Provenance controls on the Nd-Sr-O isotopic composition of sandstones: Example from Late Mesozoic Great Valley forearc basin, California." In Processes Controlling the Composition of Clastic Sediments. Geological Society of America, 1993. http://dx.doi.org/10.1130/spe284-p121.

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Fujibayashi, N., H. Kagami, and Y. Oishi. "Data report: mineralogy and Sr- and Nd-isotopic composition of gabbroic oceanic crust recovered from Holes 923A and 921E in the MARK area." In Proceedings of the Ocean Drilling Program, 153 Scientific Results. Ocean Drilling Program, 1997. http://dx.doi.org/10.2973/odp.proc.sr.153.028.1997.

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Fitton, J. G., B. S. Hardarson, R. M. Ellam, and G. Rogers. "Sr-, Nd-, and Pb-isotopic composition of volcanic rocks from the southeast Greenland Margin at 63°N: temporal variation in crustal contamination during continental breakup." In Proceedings of the Ocean Drilling Program. Ocean Drilling Program, 1998. http://dx.doi.org/10.2973/odp.proc.sr.152.251.1998.

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Conference papers on the topic "Sr and Nd isotopic compositions"

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Maria, Anton H., Joseph A. DiPietro, and Kevin F. Howard. "GEOCHEMISTRY AND SR-ND ISOTOPIC COMPOSITIONS OF PERMIAN ULTRAMAFIC LAMPROPHYRES IN SOUTHERN ILLINOIS." In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-287136.

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Song, Yingxin, Dapeng Li, Ke Geng, Pengfei Wei, Lei Shu, and Haiqin Wang. "Geochemistry and Sr-Nd Isotopic Compositions of Beijie Pluton from Northwestern Jiaodong Peninsula, Eastern China." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2437.

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Banerjee, Anupam, and Madhusoodhan Satish-Kumar. "Whole-Rock Nd, Sr and Multiple S Isotopic Compositions of Carbonatites and Alkaline Silicate Rocks from the Phalaborwa Complex, South Africa." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.120.

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Mahotkin, I. L., S. M. Sublukov, D. Z. Zhuravlev, and P. U. Zherdev. "Geochemistry and Sr-Nd isotopic composition of kimberlites, melilitites and basalts from the Arkhangelsk region, Russia." In International Kimberlite Conference Extended Abstracts 1995. University of Alberta Library, 1995. http://dx.doi.org/10.29173/ikc1886.

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Li, Tong, Liang Liu, and Xiao-Ying Liao. "Geochemistry, Sr-Nd-Pb Isotopic Compositions and Zircon U-Pb Geochronology of Neoproterozoic Mafic Dyke in the Douling Complex, South Qinling Belt, China." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.1517.

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Szymanski, Mark E., and Brandon Browne. "SR AND ND ISOTOPE COMPOSITIONS OF QUATERNARY MAFIC LAVAS OF THE GOLDEN TROUT VOLCANIC FIELD, KERN PLATEAU, SIERRA NEVADA." In 115th Annual GSA Cordilleran Section Meeting - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019cd-329019.

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Yang, Yue-Heng. "High-Precision Sr-Nd-Hf-Pb Isotopic Composition of CGSG-1, CGSG-2, CGSG-4 and CGSG-5 Reference Materials by MC-ICP-MS and TIMS." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.3011.

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Banerjee, Anupam, and Ramananda Chakrabarti. "Geochemical and Nd, Sr, Ca Isotopic Study of Leached and Whole-Rock Carbonatites." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.119.

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Yokoyama, Tetsuya, Ryota Fukai, Yuichiro Nagai, and Takafumi Hirata. "Origin and Evolution of Distinct Isotopic Variabilities for Sr, Mo, and Nd within CC and NC Reservoirs." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.3034.

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Liu, Fang, Zhao-Feng Zhang, Xin Li, and Yajun An. "Stable Ca and Radiogenic Sr Isotopic Compositions during Continental Weathering in a Vegetation-Sparse Region of South China." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.1581.

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Reports on the topic "Sr and Nd isotopic compositions"

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Roddick, J. C., R. W. Sullivan, and F. O. Dudas. Precise Calibration of Tracer Compositions For Sm - Nd Isotopic Studies. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1992. http://dx.doi.org/10.4095/132926.

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Theriault, R. J. Methods for Rb-Sr and Sm-Nd isotopic analyses at the geochronology laboratory, Geological Survey of Canada. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1990. http://dx.doi.org/10.4095/129062.

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Whalen, J. B. Geochemical and isotopic (Nd, O, Pb and Sr) data from igneous rocks of the Notre Dame Subzone and adjacent tectonostratigraphic zones, western and central Newfoundland. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2012. http://dx.doi.org/10.4095/291593.

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You might also be interested in the extended bibliographies on the topic 'Sr and Nd isotopic compositions' for particular source types:
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