Carbon and Hydrogen Existing Forms and Their Isotopic Compositions in Mantle Fluids

Abstract

Abstract: Much progress has been made on studies of isotopic compositions and existing forms of carbon and hydrogen in mantle fluid during the last two decades by researchers at home and abroad using various analytical techniques. It is commonly recognized that carbon exists in the forms of diamond in kimberlite, liquid inclusions in carbonates and xenoliths, graphite and the CO₂ erupted from mid-ridge of oceans. δ¹³C values are mainly around -5‰ with ranges of -2‰~-10‰ and -14‰~24‰. Hydrogen often exists in the forms of 0H^-, H°, liquid inclusions, super-micro inclusions, magma cells and fractures in minerals from the mantle. Its isotopic composition accounts for -30‰~-90‰. This study is helpful for well interpreting carbon and hydrogen isotopic compositions of organic, inorganic and mixed origins of hydrocarbons.

Key words: mantle, fluid, carbon isotope, hydrogen isotope, isotopic composition, existing form

CLC Number:

P591.1
P595

WU Mao-bing, LIU Chun-yan. Carbon and Hydrogen Existing Forms and Their Isotopic Compositions in Mantle Fluids[J]. Xinjiang Petroleum Geology, 2003, 24(4): 273-276.

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