Geochemistry characteristics and dolomitization mechanism of the Upper Cambrian dolomite, eastern Ordos Basin, China

2020 ◽  
Vol 55 (4) ◽  
pp. 3070-3082
Author(s):  
Siyi Fu ◽  
Chenggong Zhang ◽  
Hongde Chen ◽  
Hairuo Qing ◽  
Anqing Chen ◽  
...  
Keyword(s):  
Ordos Basin ◽  
Upper Cambrian ◽  
Geochemistry Characteristics

Quantitative identification and research of mixed-source natural gas-example of natural gas in Jingbian gas field

2014 ◽  
Vol 11 (2) ◽  
pp. 147-156
Author(s):  
Yifeng Wang ◽  
Jian Li ◽  
Jianfa Chen ◽  
Chengshan Li
Keyword(s):  
Natural Gas ◽  
Source Rock ◽  
Ordos Basin ◽  
Weighted Average ◽  
Gas Field ◽  
Lower Paleozoic ◽  
Upper Paleozoic ◽  
Geological Conditions ◽  
Weathered Crust ◽  
Geochemistry Characteristics

It is shown in natural gas proportion mixing experiments that a mixed-source natural gas is the physical combination of end member gas. Both the carbon and hydrogen isotopes in the mixed-source natural gas can be expressed by the weighted average of corresponding components content and isotopes of end member gas. Under certain geological setting, the selection of end member gas is the key to mixed-source ratio calculation. Then, it's better to estimate the mixed-source ratio with δ13C1 and component data according to the weighted average calculation formula. The analysis on natural gas geochemistry characteristics show that the natural gas extracted from Jingbian Gas Field in the Ordos Basin is mainly an upper Paleozoic coal-derived gas. In the analysis of geological conditions for reservoir forming and characteristics of natural gas, natural gas from Longtan 1 Well and Tao 6 Well were selected as the end member gases of lower Paleozoic oil-type gas and upper Paleozoic coal-type gas respectively to calculate the mixed-source ratio of natural gas in Jingbian Gas Field. The ratio of upper Paleozoic coal-derived gas mostly accounts for over 70% and its average ratio reaches 81%. Therefore, the exploration of natural gas of Ordos Basin should be focused on the upper palaeozoic coal source rock, and attention should be paid to the matching of coal source rock in the exploration of weathered crust gas deposit.

Sign in / Sign up

Export Citation Format

Share Document