As an ultra-deep fault-karst reservoir located in the Tarim Basin of Xinjiang,the Shunbei oil and gas field prosses the characteristics of the large burial depth and fault development in the target formations.This oil and gas field is difficult to explore due to the low signal-to-noise ratio and low resolution of seismic signal data since seismic signals are absorbed by the desert surface and thereby suffer severe attenuation.The microbial prospecting developing based on the theory of vertical hydrocarbon microseepage can detect the oil and gas-bearing properties of fault zones.This technology,combined with geophysical exploration,can improve the success rate of the prediction of the oil and gas-bearing properties of fault zones.This experimental study of microbial prospecting in fault zone No.5 in the Shunbei oil and gas field shows that the abundance anomalies of hydrocarbon-consuming microorganisms show good near-surface response to fault-karst reservoirs.Compared to areas with vegetation,hydrocarbon-consuming microorganisms (including methane- and butane-oxidizing bacteria) as indicators of microbial prospecting in desert areas are characterized by low measured values and slight fluctuation.However,hydrocarbon-consuming microorganisms can better reflect the near-surface information induced by the vertical microseepage of deep-buried oil and gas since they are less disturbed by other microbial communities due to the special ecological conditions in desert areas.According to the application results,the high-amplitude anomalies of both methane- and butane-oxidizing bacteria are primarily distributed in the vicinity of fault zone No.5,and favorable anomalies also occur in the vicinity of fault zone No.1 in the Shunbei oil and gas field.Furthermore,the strike of these anomalies roughly coincides with that of fault zones,indicating that the microbial anomaly zones correlate strongly with fault-karst reservoirs.Therefore,the microbial prospecting for hydrocarbons has great application prospects in the exploration of the fault-karst reservoirs.
曹飞, 杨敏, 鲍典, 陈银节, 王国建. 油气微生物对顺北断溶体油藏的近地表响应[J]. 物探与化探, 2022, 46(3): 678-684.
CAO Fei, YANG Min, BAO Dian, CHEN Yin-Jie, WANG Guo-Jian. Near-surface response of hydrocarbon-consuming microorganisms to the fault-karst reservoirs in Shunbei oil and gas field. Geophysical and Geochemical Exploration, 2022, 46(3): 678-684.
Deng S, Li H L, Zhang Z P, et al. Characteristics of differential activities in major strike-slip fault zones and their control on hydrocarbon enrichment in Shunbei area and its surroundings,Tarim Basin[J]. Oil & Gas Geology, 2018, 39(5):878-888.
Kong J B, Zhang D C, Gao Y, et al. A study of static correction and deno ising method for low signal to noise ratio seismic data from the desert area of tarim basin and its application[J]. Geophysical and Geochemical Exploration,2012, 2005, 29(3):257-260.
Wang G J, Tang Y P, Zhao K B, et al. Application of hydrocarbon geochemical exploration technique inoil and gas exploration in western Sichuan depression,China[J]. Geological Bulletin of China, 2009, 28(11):1643-1649.
Zhang S C, Gao Z Y, Li J J, et al. Identification and distribution of marine hydrocarbon source rocks in the Ordovician and Cambrian of the Tarim Basin[J]. Petroleum Exploration and Development, 2012, 39(3):285-294.
Zhang B T, Yu B S, Zhu G Y, et al. Research on hydrocarbon distribution regularity and main accumulationcontrolling factors of Tazhong northern slope hydrocarbon-rich region[J]. Earth Science Frontiers, 2015, 22(1):271-280.