Natural gas origins of the large-medium sized gas fields in China

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:427039

Dai, Jinxing ^[1]; Li, Xianqi; Qin, Shengfei

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1. Research Inst. of Petroleum Exploration and Development, Beijing (China)

Large-medium sized gas field refers to the gas field with proved reserves over 100 X 10{sup 8}m{sup 3}. By the end of 1994, 30 large or medium sized gas fields have been found in China (except for Taiwan province), of which the proved gas reserves account for 71% of the total chinese gas reserves. And four origins of the natural gases of large-medium sized gas fields have been determined in China: (1) Oil-type gas holds a dominant position of the gases, is primarily dry gas with {delta}{sup 13}C{sub 1} values ranging from -39.82{per_thousand} to -31. 93{per_thousand}, R/Ra ratio values being 0.003 {approx} 0.150; (2) Coal-formed gas takes the second place of the gases, is predominately wet gas, with {delta}{sup 13}C{sub 1} values from -39.55{per_thousand} to -27.80{per_thousand}, and R/Ra ratio values of 0.016{approx}0.686; (3) Mixed-gas is mainly dry gas, with {delta}{sup 13}C{sub 1} values varying within -35.87{per_thousand}{approx}-33.40{per_thousand}, R/Ra ratio values being 0.014{approx}0.040; (4) Biogenic gas is only dry gas, with {delta}{sup 13}C{sub 1} values from -68.54{per_thousand} to -64.90{per_thousand}, R/Ra ratio values of 0.030-0.305. In a word, this paper elaborates the natural gas origins of chinese large-medium sized gas fields, based on the full and accurate data of gas components, carbon isotopic compositions of alkane gases ({delta}{sup 13}C{sub 1-4}) and Carbon dioxide ({delta}{sup 13}C{sub CO{sub 2}}), and the associated helium isotopes (R/ Ra).

• OSTI ID: 427039
• Report Number(s): CONF-960527--
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
CHEMICAL COMPOSITION
CHINA
COAL DEPOSITS
METHANE
NATURAL GAS
NATURAL GAS DEPOSITS
NATURAL GAS FIELDS
ORIGIN
RESERVES