油气化探方法在方正断陷油气勘探中的应用

方正断陷近地表油气地球化学勘探工作采用土壤酸解烃、蚀变碳酸盐(△C)和荧光光谱分析技术,筛选出多个反映油气异常的指标,圈定出红旗Ⅰ级综合异常、西六方Ⅱ级综合异常和宝兴Ⅲ级综合异常。红旗Ⅰ级综合异常和西六方Ⅱ级综合异常具有异常强度大、平均衬度和评价指数高等特征,为最有利含油气远景区,是进一步勘探的主要方向;而宝兴Ⅲ级综合异常强度弱,仅具一定的参考意义。方3井、方401井、方6井和方4井均部署在西六方Ⅱ级综合异常上,获得工业油气流,证实了异常下油气的存在。

Application of oil and gas geochemical exploration method on oil and gas exploration in Fangzheng fault depression

Multiple techniques such as soil acidolysis hydrocarbon,alteration carbonate and fluorescence spectrum analysis,have been used to select the indicators of anomalous hydrocarbon concentration in near-surface oil and gas geochemical exploration of Fangzheng fault depression. Three anomalous areas were identified including Hongqi--I,Xiliufang--II and Baoxing--III comprehensive anomalies. The Hongqi--I anomaly and Xiliufang--II anomaly,characterized by rather strong anomalous signal,high average contrast and evaluation index,are regarded as the main prospects. The anomalous signal in Baoxing--III is weak,which is significant for reference. From the Well Fang--3,Fang--401,Fang--6 and Fang--4 all located on Xiliufang--II anomaly,the commercial oil obtained,which confirmed the petroleum occurrence underlying the anomaly.