沉积盆地侵入岩区的异常“温度场、压力场和地球化学场”与油气的关系——以东营凹陷纯西辉长岩为例

通过岩石学、有机地球化学等分析 ,发现纯西辉长岩周围烃源岩具有有机质含量极低、高熟和裂缝发育以及油气比较丰富等特征 .研究表明 ,其根源是辉长岩形成的特殊温度场、压力场和地球化学场 ;辉长岩形成的异常高温大大促进了烃源岩热演化 ,并提高了生烃量 ;高压产生的大量裂缝为烃源岩排烃和油气聚集提供了通道和储集空间 ;而辉长岩带来的深源氢对烃源岩起到加氢作用 ,扩大了生烃量

Relationship between the temperature, pressure and geochemistry fields in the intrusive rock in sedimentary basin and oil-gas reservoirs - taking Chunxi gabbros in Dongying Sag as an example

According to the lithologic and organic geochemical analyses of Chunxi gabbros in Dongying Sag, it is found that the hydrocarbon source rocks around Chunxi gabbros have very low organic matter content and high maturity, cracks are very developed in them, and they have rich oil and gas. The related studies show the characteristics of the hydrocarbon source rocks have something to do with the temperature, pressure and geochemistry fields when the gabbros form. The high temperature greatly accelerates the thermal evolution of the hydrocarbon source rocks, and the hydrocarbon generating quantity is increased; the high pressure produces a quantity of cracks, and the cracks provide the channels for the expulsion of the hydrocarbon and the space for the accumulation of oil and gas; the hydrogen brought by the gabbros has hydrogenation to the hydrocarbon source rocks, and the hydrocarbon generating quantity is also increased