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Zircon U-Pb age, Trace Element, and Hf Isotopic Compositions of Nordmarkite in the Lizhuang Rare Earth Element Deposit in the Western Margin of the Yangtze Block
nordmarkite REE deposit Hf isotopic characteristics of zircon Lizhuang
2018/4/10
The Mianning–Dechang (MD) rare earth element (REE) belt, located in the northern Kangdian axis (KDA) in the western margin of the Yangtze platform, is one of the most economically significant REE mine...
Two Types of Granites in the Western Yangtze Block and Their Implications for Regional Tectonic Evolution: Constraints from Geochemistry and Isotopic Data
I-type granite S-type granite geochemistry petrogenesis tectonic setting Western Yangtze Block
2018/4/10
In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic-magmatic evolution of the region. However, their petrogenesis and...
New constraints on shergottite petrogenesis from analysis of Pb isotopic compositional space: Implications for mantle heterogeneity and crustal assimilation on Mars
shergottite Pb isotopes Martian geochemistry crustal assimilation mantle heterogeneity
2017/4/10
Geochemical studies of shergottites (Martian basalts) based on Rb-Sr, Sm-Nd, and Lu-Hf isotopic systematics have
provided clues to understanding the geochemical evolution of the Martian mantle and id...
Surface layer Nd isotopic composition of ferromanganese crusts collected from the Takuyo-Daigo Seamount reflects ambient seawater
ferromanganese (Fe-Mn) crust Nd isotopic composition seawater Takuyo-Daigo Seamount
2017/4/10
The neodymium (Nd) isotopic composition of the surface layers of eleven ferromanganese crust samples collected
from the Takuyo-Daigo Seamount (northwest Pacific Ocean) was determined. This is the fir...
Controlling factors in stalagmite oxygen isotopic composition and the paleoprecipitation record for the last 1,100 years in Northeast Japan
ortheast Japan stalagmite d18O growth rate precipitation famine records
2017/4/10
Stable oxygen isotopic analysis was performed on the UT-A stalagmite with annual microbanding from the Uchimagido
Cave in Iwate Prefecture on the Pacific side of Northeast Japan. High-resolution anal...
Presolar silicate grains: Abundances, isotopic and elemental compositions, and the effects of secondary processing
presolar grains silicates nucleosynthesis isotopes AGB stars
2017/4/10
Close to a thousand presolar silicate grains have been identified since their initial discovery in interplanetary dust
particles (IDPs) just over ten years ago. Studies have shown that silicates are ...
Crude oil He and Ar isotopic characteristics and their geochemical significance: an example from the Gangxi oil field in the Huanghua depression
crude oil noble gas tracing Gangxi oil field Huanghua depression
2015/9/10
Sampled from the Gangxi oil field in the Huanghua depression, Bohaiwan Basin, the crude oil He and Ar isotopic
compositions and their geochemical significance were investigated. The result shows that...
Chemical and isotopic composition of fumarolic gases at Iwate volcano, Japan, during and after seismic activity in 1998: implications for the modification of ascending volcanic gases
Volcanoes volcanic earthquakes expectations and volcanic gases seismic activity the concentration of hydrochloric acid
2015/8/27
In 1998, there were many volcanic earthquakes recorded at Iwate volcano, Japan. Although an eruption was anticipated, it never occurred. Fumarolic gases were sampled at the volcano on six occasions du...
Long time-series of chemical and isotopic compositions of Vesuvius fumaroles: evidence for deep and shallow processes
Chemical and isotopic composition mount Vesuvius jet orifice
2015/8/27
Long time-series of chemical and isotopic compositions of Vesuvius fumaroles were acquired in the framework of the volcanic surveillance in the 1998-2010 period. These allow the identification of proc...
A 180-Million-Year Record of Sea Level and Ice Volume Variations from Continental Margin and Deep-Sea Isotopic Records
180-Million-Year Record Sea Level and Ice Volume Variations Continental Margin Deep-Sea Isotopic Records
2015/7/9
The geologic record provides constraints on the rates, amplitudes, and mechanisms controlling globally averaged (eustatic) and relative (eustatic plus subsidence/uplift) changes of sea level on variou...
Photosynthesis leaves behind a unique calling card, a chemical signature that is spelled out with stable oxygen isotopes, according to a new study in Science. The findings suggest that similar isotopi...
The Effects 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 of Sediments Cretaceous Western Interior Seaway Oceanic Anoxic Event 3 Mesa Verde CO, USA
2014/11/4
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...
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...