【摘要】 通过对塔中含油气系统的研究,发现它难以用传统的含油气系统方法来描述。它主要有二个油源区三套生油岩,发育有三套储层;不同油源在不同时期生成的油气在储层内共生、甚至相互混合,使油气成因复杂。据此提出它是一个复合型含油气系统。在此基础上,进一步指出复合型含油气系统的特点是多油源、多期成烃,油气成因复杂,出现在迭合型盆地。并针对这些特点,初步提出了工作思路及描述方法。更多还原

【Abstract】 The Tazhong petroleum system is geographically located in the central Tarim Basin, including the Tazhong Uplift, the North Slope and the south partof the Manjiaer Depression. The total thickness of early Paleozoic to Cenozoic sediments reaches to 6 500～9 500 m. The Manjiaer Depression and the North Slope are the two major petroleum source areas with three sets of source rocks: Cambrian black shales and Ordovician dark carbonates of the Manjiaer Depression and Ordovician argillaceous limestones of the North Slope. There are three sets of reservoir seal rock combinations in this petroleum system. The main periods foroil generation from these source rocks occurred during Middle Silurian to EarlyDevonian, Cretaceous to Early Triassic, and Tertiary. There were three corresponding phases of petroleum migration. Well developed thrust faults and unconformity surfaces in this area provided the main pathways for petroleum migration. As some of the faults cut through all the lower Paleozoic strata, the oil in any given reservoir rock may be actually a mixture of oils from different sources, complicating the origin and properties of the hydrocarbons in the reservoir, and forming a hybrid petroleum system. On the basin of this, the features of a hybrid petroleum system are suggested, mainly including: multi oil sources, multi peaks for oil generation, complicated petroleum origins and occurrences in superimposed basin. A method to describe a hybrid petroleum system is discussed. It presents three important features of a hybrid petroleum system: amounts of oil sources, oil origins in a reservoir, and petroleum prospective. The hybrid petroleum systems may be widespread in Chinas large to medium size superimposed petroleum basins and great attention should be paid to this possibility in the exploration of these basins.更多还原