微生物方法在油气勘探中的试验研究——以松辽盆地十屋断陷为例

微生物油气勘查技术作为一种近地表勘探方法，通过检测近地表土壤中的这些噬烃菌数量变化，从而预测深部油气藏。在松辽盆地十屋断陷开展的微生物油气勘探的试验研究中，为了反映地下油气微渗漏在地表的真实体现，抑制干扰因素，获得与油气微渗漏有关的微生物异常，选择了3种微生物指标：甲烷氧化菌、纤维素分解菌、硫酸盐还原菌。检测油气藏上方近地表土壤中3种菌落的数目，然后根据它们之间的关系，找出微生物异常点，结合其它地球化学指标对微生物异常进行了分析，并推测地下油气的分布规律，同时探讨了微生物、地球化学异常与石油地质的关系，油气预测效果较显著。

EXPERIMENTAL STUDY OF MICROBIOLOGICAL PETROLEUM EXPLORATION: TAKING SHIWU FAULT DEPRESSION OF THE SONGLIAO BASIN AS AN EXAMPLE

Microbial oil survey technique (MOST) is a near-surface petroleum exploration method, which predicts the occurrence of deep oil and gas reservoirs by detecting change of the amount of hydrocarbon-eating bacteria in soil. For experimental study of microbiological petroleum exploration in Shiwu fault depression of the Songliao Basin, three kinds of microbiological indicators, including methane-oxidizing, cellulose decomposing and sulfate-reducing bacteria, are selected to reflect the surface expression of subsurface microseepage of hydrocarbons, to suppress interference factors and to obtain relevant microbial anomaly. The numbers of these three kinds of bacteria in near-surface soil above oil and gas pools are detected and the microbial anomaly points are determined according to their relationships. The microbial anomalies are analyzed in combination with other geochemical indicators, and the subsurface distribution patterns of oil and gas are predicted. The relationship between microbial and geochemical anomalies and petroleum geology in the study area is also discussed. The effects of oil/gas prediction are remarkable.