焉耆盆地油气藏特征与成藏模式

焉耆盆地是我国西部众多中新生代小型含煤盆地之一。 1993年开始进行规模性勘探 ,先后探明了宝浪油气田和本布图油田。该盆地油气藏圈闭成因类型主要为与逆断层有关的背斜、断背斜油气藏 ;油气具有典型煤成烃特征 ,油气藏流体相态类型丰富 ,气油比高 ,流体性质好 ;油气藏几何类型以层状边水为主 ;油气聚集层位主要为侏罗系三工河组 ,油气层分布集中 ,单井油气层厚度大 ,埋深适中 ;侏罗系储集层主要为低孔低渗的孔隙型碎屑岩 ;压力系数较高 ,产能中等 ;单储系数低 ,储量丰度中等。通过烃源岩生排烃史、圈闭发育史和成藏史分析 ,研究了油气藏的形成机理 ,探讨了成藏模式

Characteristics and pool-forming pattern of oil and gas reservoirs in Yanqi basin

Yanqi basin is one of the small coal bear ing Mesozoic and Cenozoic basins in western China where two oil gas fields with four oil bearing blocks have been found successively. Study revealed that the genetic types mainly are anticline related to reverse fault and faulted anticline oil and gas reservoirs; they have typical characteristics of coal derived hydrocarbon and fluid phase types are rich; gas oil ratio is high and fluid properties are good; pool geometric types mainly are layered edge water; oil and gas accumulation horizons largely are the Sangon ghe Formation of Jurassic with centralized distribution, large single layer thic kness and moderate buried depth; the Jurassic reservoirs mainly are pore type clastic rocks with low porosity and low permeability; formation pressure coeffic ient is high and productivity is moderate; unit reserve factor is low and reserv e abundance is moderate. The pool forming mechanism and pattern are studied thr ough analyzing hydrocarbon generation and expulsion history, trap development hi story and pool forming history.