曹台变质岩潜山油气的运移与成藏特征

Petroleum Migration and Accumulation Characters of Caotai Metamorphic Buried Hill

基岩潜山油藏具有油气成藏的两种特征 ,即外来的油源和裂缝性储集空间 .辽河油田曹台潜山油藏的形成与烃源岩的演化和潜山圈闭的形成演化以及油气的运移密切相关 .在岩心观察与描述的基础上 ,利用薄片观察裂缝充填的方解石碳氧同位素分析 ,结合基岩潜山圈闭的形成与演化过程 ,探讨了辽河大民屯凹陷曹台变质岩潜山的成藏特征 .研究表明 ,潜山西侧凹陷烃源岩于沙二期 (Es2 )成熟供烃 ;潜山圈闭在沙三期末 (Es3 )定型 ,在东营早期 (Ed)成藏 ;边界断层为油气运移提供了良好的通道 ;油气以垂向运移 ,侧向注入的形式运移至潜山圈闭中 ;基岩中发育的裂缝系统为油气的储集空间 ;形成了烃源岩生烃、储集、运移和圈闭演化相互匹配良好的成藏模式 .

There are two oil and natural gas accumulation characters in basement rock reservoir which are all extraneous source of oil and porous fractured reservoir.As a kind of basement container rocks,the metamorphic pool forming has relationship with source rock evolution, trap formation and oil migration.Based on the core observation and description,the carbon and oxygen isotopes of calcite filled in fissures were analysed.The oil migration and accumulation characters of Caotai buried hill are studied by analyzing its trap forming and evolution.The researches indicate that the basement reservoir forming has suitable accouplement with source rock maturation,oil migration and trap evolution.The source rock in west sag maturated in the period of Shahejie No.2 group (Es 2).The buried hill trap has formed in the period of Shahejie No.3 group (Es 3) and forming reservoir in the period of early Dongying formation (Ed).The boundary fault favored access for oil migration.Oil entered into the buried hill trap through vertical migration along the fault and side injected.The fissures system in basement rock was porous spaces.