Genetic origins of marine gases in the Tazhong area of the Tarim basin, NW China: Implications from the pyrolysis of marine kerogens and crude oil
Genetic origins of marine gases in the Tazhong area of the Tarim basin, NW China: Implications from the pyrolysis of marine kerogens and crude oil
复制标题
塔里木盆地塔中地区海洋气体成因：海洋干酪根和原油热解的启示
DOI：
10.1016/j.coal.2010.01.012
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发表时间：
2010-05
影响因子：
5.6
通讯作者：
Xiao, Xianming
中科院分区：
文献类型：
--
作者：
Tian, Hui;Gan, Huajun;Guo, Liguo;Yang, Liguo;Wilkins, Ronald W. T.;Xiao, Xianming
Although abundant natural gases have been discovered in Carboniferous and Ordovician reservoirs in the Tazhong area, central Tarim basin, their genetic origins is still an open question because of significant variations in chemical and carbon isotopic compositions. In the present study, three samples representing the possible gas sources were pyrolyzed using sealed gold tubes to investigate their gas potentials, and chemical and carbon isotopic signatures. The samples were a crude oil, a low maturity kerogen and a high maturity kerogen. The results show that the chemical and isotopic compositions of gaseous pyrolysates from the three samples are quite different. Generally, the gases from oil cracking are compositionally wetter and isotopically lighter than those from kerogen cracking at similar thermal levels. The large quantities of methane experimentally observed in oil cracking gases are mainly associated with the re-cracking of wet gases at very high maturity levels. Methane in gases derived from kerogen, especially high maturity kerogen, in contrary, is mainly generated by the demethylation reaction. The diagrams of δ13C1vs. δ13C2–δ13C3and C2/C3vs. δ13C2–δ13C3, along with natural gas plots, have proven to be a very effective tool in the genetic interpretation of natural gases from kerogen and oil cracking in the Tarim basin. Their combined application shows that two types of gas source can be identified in the Tazhong area. The first type is oil cracking gas, mainly discovered in Carboniferous reservoirs of the central fault horst area, but also partly in Ordovician reservoirs, such as in the wells TZ45, TZ44b and TZ 16. The other is kerogen cracking gas occurring largely in Ordovician reservoirs, especially in the North Slope area. The two types of gases, however, are mixed in many reservoirs as their generation is overlapped in time and/or space. This mixing process is especially obvious for methane.
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影响因子：
3
作者：
Hill, RJ;Tang, YC;Kaplan, IR
通讯作者：
Kaplan, IR
影响因子：
3
作者：
H. Tian;X. Xiao;R. Wilkins;Huajun Gan;Zhong-yao Xiao;Dehan Liu;Liguo Guo
通讯作者：
H. Tian;X. Xiao;R. Wilkins;Huajun Gan;Zhong-yao Xiao;Dehan Liu;Liguo Guo
影响因子：
3.9
作者：
JENDEN, PD;NEWELL, KD;WATNEY, WL
通讯作者：
WATNEY, WL
影响因子：
5.3
作者：
Behar, F;Budzinski, H;Tang, Y
通讯作者：
Tang, Y
影响因子：
4.2
作者：
H. Tian;X. Xiao;R. Wilkins;Xianqing Li;Huajun Gan
通讯作者：
H. Tian;X. Xiao;R. Wilkins;Xianqing Li;Huajun Gan