State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of S...

a Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing 100029, China b Graduate University of Chinese Academy of Sciences, Beijing 100049, China c Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China d State Key Laboratory of Environmental Geochemistry, Institute of Geoc...

The foundations of stable isotope geochemistry were laid in 1947 by Urey’s classic paper on the thermodynamic properties of isotopic substances and by Nier’s development of the ratio mass spectrometer. Before discussing details of the naturally occurring variations in stable isotope ratios, it is useful to describe some generalities that are pertinent to the field of non-radiogenic isotope geoc...

Abstract Large meteorite impacts have a profound effect on the Earth's geosphere, atmosphere, hydrosphere and biosphere. It is widely accepted that early Earth was subject to intense bombardment from 4.5 3.8 Ga, yet evidence for subsequent bolide during Archean Eon (4.0 2.5 Ga) sparse. However, understanding timing magnitude of these events important, as they may triggered significant change po...

Fluoride (F–) pollution in groundwater of the Older Alluvial Plain (OAP) Delhi has been reported as a major problem. About 34% samples collected for this study had F– level beyond permissible limit; with concentration range 0.14–3.15 mg/L (average 1.20 mg/L). In context, article first time attempts on genesis ions chemistry and OAP by going statistical analysis to sediment geochemistry, chemica...

Isotopic analysis can be performed on minerals, rocks, soil, tissue, gases, and liquids – just about anything. In view of the broad possibilities, we will only cover a few generalities here. In most instances, the element to be analyzed must be first isolated and purified before it can undergo isotopic analysis in a mass spectrometer. Purification is necessary to avoid isobaric interferences an...

Introduction Recent work has proposed that the nitrogen isotopes in marine sediments can be impacted by anaerobic oxidation of methane (AOM), since uptake methanotrophic archaea (ANME) modifies isotope compositions bulk sediment. Thus, unraveling AOM-driven cycle sulfate-methane transition zone (SMTZ) becomes significant. Additional study between sediment and interstitial water SMTZ is needed. ...