搜索结果: 1-15 共查到“地球科学总论 isotopic”相关记录20条 . 查询时间(0.014 秒)
An Isotopic Perspective On Climatic Change In Tropical South America From The Modern Through The Last Glacial Period
Earth sciences Isotopes Tropical South America Speleothem Precipitation variability Proxy reconstructions
2014/10/22
The overarching goal of this study is to investigate the nature of precipitation variability in tropical South America over interannual to orbital timescales during the last 50,000 years. In order to ...
Th Effcts of Sea Level Change on the Molecular and Isotopic Composition of Sediments in the Cretaceous Western Interior Seaway: Oceanic Anoxic Event 3, Mesa Verde, CO, USA
Sea Level Change on the Molecular Isotopic Composition Sediments Cretaceous Western Interior Seaway Oceanic Anoxic Event 3 Mesa Verde CO USA
2014/10/22
Cretaceous Oceanic Anoxic Events (OAEs) represent periods of enhanced burial of organic matter in black shale in marine, continental margin, and epicontinental settings around the globe. Compared to o...
Exploring Isotopic Signatures of Lake El'gygytgyn Sediments for Evidence of Anoxia and Methane Cycling over the Past 50,000 Years
Exploring Isotopic Signatures Lake El'gygytgyn Sediments Evidence of Anoxia and Methane Cycling over the Past 50,000 Years
2014/10/21
Compound specific isotope analysis of lake sediments is a powerful tool in deciphering evidence of changing climatic and paleoenvironmental conditions through time. Isotopic analysis of Lake El’gygytg...
Helium and Argon Isotopic Studies of Fossil Material and the Theoretical Evolution of He and Ar in Earth’s Atmosphere through Time
Fossils Argon Helium Isotopes Atmospheric Evolution
2012/10/31
We analyzed the elemental concentrations and the isotopic compositions of helium and argon in Cambrian to Jurrassic aged Gastropod, Ammonite and Trilobite fossils in order to examine variation in thes...
Preserved Sm-Nd Isotopic Composition as Useful Provenance Indicators in Neoproterozoic Sandstones in the Voltaian Basin, Ghana
Isotope Model Age Provenance Sandstone Voltaian Basin
2012/7/20
The provenance of sandstones derived from theLower Voltaian Kwahu-Morago Group and the Middle Voltaian Oti-Pendjari Group of the Neoproterozoic Voltaian basin are discriminated by their Sm-Nd Isotopic...
Geochemical and Sr-Nd Isotopic Characteristics of Post-Collisional Calc-Alkaline Volcanics in the Eastern Pontides (NE Turkey)
earth siences rocks gneisses
2011/3/21
Major, trace element, K-Ar age and Sr-Nd isotopic data are presented for the Eocene Torul volcanics in the eastern Pontide orogenic belt (NE Turkey). The studied rocks are composed of basaltic andesit...
Unusually negative nitrogen isotopic compositions (δ15N) of mangroves and lichens in an oligotrophic,microbially-influenced ecosystem
negative nitrogen isotopic compositions mangroves lichens microbially-influenced ecosystem
2009/12/11
Extremes in δ15N values in mangrove tissues and lichens (range =+4 to −22‰) were measured from a mangrove forest ecosystem located on Twin Cays, offshore islands in Belize, Central America. The ...
Organic matter sedimentation in the western Barents Sea region:Terrestrial and marine contribution based on isotopic composition and organic nitrogen content
Organic matter sedimentation western Barents Sea region Terrestrial and marine contribution
2009/12/2
Here, we present bulk organic geochemical data from a spatial grid of surface samples from the western Barents Sea region. The results show that the distribution of organic carbon in surface sediments...
Growth phase dependent hydrogen isotopic fractionation in alkenone-producing haptophytes
Growth phase dependent hydrogen isotopic fractionation alkenone-producing haptophytes
2009/8/19
Recent works have investigated use of the hydrogen isotopic composition of C37 alkenones (δDK37s, lipid biomarkers of certain haptophyte microalgae, as an independent paleosalinity proxy. We discuss h...
Stratospheric isotopic water profiles from a single submillimeter limb scan by TELIS
Stratospheric isotopic water profiles single submillimeter limb scan TELIS
2009/8/5
Around 490 GHz relatively strong HDO and H218O emission lines can be found in the submillimeter thermal-emission spectrum of the Earth's atmosphere, along with lines of the principal isotopologue of w...
U-Pb zircon SHRIMP ages,geochemical and Sr-Nd isotopic compositions of the Early Cretaceous I-type Sarıosman pluton,Eastern Pontides,NE Turkey
SHRIMP dating Sarı osman pluton mineral chemistry I-type Sr-Nd isotope geochemistry eastern Pontides
2009/4/21
The petrogenesis and U-Pb SHRIMP zircon ages of the Late Cretaceous Sarıosman pluton in the Eastern Pontides is investigated by means of whole-rock Sr-Nd isotope data with field, petrographic and...
Calcium isotopic composition of high-latitude proxy carrier Neogloboquadrina pachyderma (sin.)
isotopic composition high-latitude proxy carrier Neogloboquadrina pachyderma
2009/1/5
The accurate reconstruction of sea surface temperature (SST) history in climate-sensitive regions (e.g. tropical and polar oceans) became a challenging task in palaeoceanographic research. Biogenic sh...
Fluxes and 13C isotopic composition of dissolved carbon and pathways of methanogenesis in a fen soil exposed to experimental drought
Fluxes 13C isotopic composition dissolved carbon pathways methanogenesis
2008/10/28
Peatlands contain a carbon stock of global concern and significantly contribute to the global methane burden. The impact of drought and rewetting on carbon cycling in peatland ecosystems is thus curre...
Reconstruction of the biogeochemistry and ecology of photoautotrophs based on the nitrogen and carbon isotopic compositions of vanadyl porphyrins from Miocene siliceous sediments
Reconstruction biogeochemistry ecology photoautotrophs isotopic compositions
2008/5/15
We determined both the nitrogen and carbon isotopic compositions of various vanadyl alkylporphyrins isolated from siliceous marine sediments of the Onnagawa Formation (middle Miocene, northeastern Jap...
期刊信息
篇名
Sm-Nd and Rb-Sr isotopic chronology and cooling history of ultrahigh pressure metamorphic rocks and their country rocks at Shuanghe in the Dabie Mountains, central China.
语种
英文
撰写或编译
撰写
作者
Li ...