鄂尔多斯东南部长_2~1油层段开发层系厘定及在油田开发中的应用

Collation of development layer series about Chang_2~1 oil member and application to oilfield development in the southeast of Ordos Basin,China

探讨鄂尔多斯盆地延长组岩石地层学及含油气层系的划分,为准确、高效地开发长12油层段提供理论依据和简便易行的工作方法。从延长组的命名及其沿革入手,分析其岩石地层和含油气层系划分的现状,严格按照行业规范,将鄂尔多斯盆地内中—晚三叠世形成的一套河—湖相沉积物划分为:延长群含油气层系,其2级单位是10个油层组(长1—长10),其中的长2油层组可分作3个油层段(长12—长32)。长12油层段又可进一步地细分、厘定为3个复层和若干个单层。开发实践证明,长12油层段开发层系的科学划分和精确厘定是该区油田开发最基础、最关键的研究。

This paper approaches the lithostratigraphy and the division of oil- and gas-bearing layer series about Middle-Upper Triassic Yanchang Formation in Ordos Basin. The aim is to supply theory ground and easy working method for developing Chang1/2 oil member accurately and high effectively. Starting with the name of Yanchang Formation and its evolution, the paper analyses the present state of [ithostratigraphy and the oil- and gas-bearing layer series. According to the trade standard strictly, a suit deposits of river-lake facies sediments formed in Middle Late Triassic in Ordos Basin are divided as Yanchang Group oil- and gas-bearing layer series. There are ten oil- and gas-bearing layer sets （Changl-Changl0） as its second unit, and the Chang2 oil- and gas-bearing layer set can be divided into three oil- and gas-bearing layer members （Chang12-Changa2）. Change2 oil-bearing layer member can be divided in detail and finely defined into three compound oil- and gas-bearing horizons and some single oil layers further. The development practice has proved that the scientific division and accurate collation of Chang1/2 oil layer member is the most basic and the most key study when we develop the oilfield in this area.