鄂尔多斯盆地延长组油气初次运移特征

以泥岩压实、埋藏史及生烃特征为主要依据，分析了鄂尔多斯盆地三迭系延长组长７油层组烃源岩油气初次运移的动力、产生深度、运移时间、运移方向及途径。结果表明，本区油气初次运移的主要动力是长７油层组广大范围发育的泥岩欠压实现象所产生的高过剩压力，烃源岩门限深度及异常压实起始深度决定了本区烃源岩初次运移的深度，油气初次运移的时期主要发生于Ｋ１２时期和Ｋ１３时期，油气直接从烃源岩垂向进入邻近储集层将是本区最为重要的运移途径之一，烃源岩侧向发生相变的地带往往也可以形成比较良好的排烃条件

Characteristics of Hydrocarbon Primary Migration in Eerduosi Basin

Based mainly on the mudstone compaction,burial history and the characteristics of hydrocarbon generation,the paper analysed the motive force,depth,time and direction of the primary migration in No.7 Strata of Yanchang FM in Eerduos Basin.The results show that the primary migration occured because of the excessive pressure produced by the insufficient compaction of mudstone developed in the broad zone of No.7 Strata;The depth of the migration is decided by the maturity depth and the starting depth of abnormal compaction;The primary migration occured mainly in the periods of K 12 and K 13 deposition and the direction of migration is mainly upward.The large scale of connected zones between sourcerock and the reservoir and the zone where facies transition took place are more favourable places for hydrocarbon expelling.