排烃机理及厚度探讨  

Discussion on mechanism and thickness of hydrocarbon expulsion

作　　者：陈安定[1] 

机构地区：[1]中国石油化工股份有限公司江苏油田分公司地质科学研究院,江苏扬州225009

出　　处：《复杂油气藏》2010年第3期1-5,共5页Complex Hydrocarbon Reservoirs

基　　金：中国石油化工股份有限公司(P05004)

摘　　要：为研究排烃,苏北盆地建立了4条地球化学剖面。根据剖面源岩在排出路线上未反映出烃浓度的梯度变化,以及各处源岩仍保持原有地球化学特征等说明微孔道排烃的假说不成立。研究表明,层段之间存在异常压力释放及排烃的不均衡,这种不均衡与层段之间的生烃能力差异有密切关系。根据泥岩中观察到的大量微裂隙和层段间的排烃差异,提出烃类排出是一个从压力积聚到压力释放的幕式涌流过程,通过生烃达到地层增压、形成层面破裂和纵向微裂隙,然后排出。微裂隙排烃具有"优势生烃者先排烃、段与段之间差异为主、无厚度限制"三大特点。To study hydrocarbon expulsion of Suibei Basin, four geochemical profiles were set up. According to the absent of hydrocarbon concentration - gradient change of section of source rocks, which have geochemical characteristics of the original, on expulsion way, it is illustrated that the hypothesis of micro - bores hydrocarbon expulsion does not hold. The non -equilibrium of abnormal pressure releasing and hydrocarbon expulsion between layers is being,which is closely associated with hydrocarbon generation ability. According to a lot of micro - cracks discovered in mudstone and the hydrocarbon expulsion differentiation between neighbor layers, it is proposed that the hydrocarbon expulsion is an episodic expulsion process from pressure accumulation to pressure releasing, which include formation pressure increased by hydrocarbons gen- eration, and layer break at first and vertical micro - crack formation, and then hydrocarbon expulsion. The main features of micro -crack hydrocarbon expulsion are following as：l ） predominance source rocks expelled hydrocarbons earlier;2） expulsion is mainly from difference between neighbor layers;3 ） there is no limit of thickness.

关 键 词：排烃机理 排烃厚度 微裂隙排烃 微孔道排烃 初次运移 苏北盆地 

分 类 号：TE122.113[石油与天然气工程—油气勘探]