柴达木盆地油砂山油田上干柴沟组高分辨率层序地层分析

运用Cross提出的高分辨率层序地层学理论，综合测井、岩心等资料，对油砂山油田上千柴沟组进行分析，将上干柴沟组地层划分为15～20个短期旋回、6个中期旋回和1个长期旋回。分析了各级次旋回内部沉积相特征及演化规律，建立了全区以中期基准面升、降半旋回相域为等时地层单元的高分辨率层序地层格架，以此为指导精细刻画了上干柴沟组地层的砂体展布情况，指出长期基准面上升早期和下降晚期及三角洲体系为砂体发育的最有利部位。

High-resolution sequence stratigraphic analysis of the Upper Ganchaigou Formation in the Youshashan Oil Field, Qaidam Basin, Qinghai

In the light of the high-resolution sequence stratigraphic theory presented by Cross, and well logs and core observation in this study, the strata of the Upper Ganchaigou Formation in the Youshashan Oil Field, Qaidam Basin, Qinghai may be divided into 15 to 20 short-term, 6 medium-term and 1 long-term base-level cyclic sequences. The present paper focuses on the analysis of sedimentary facies and evolution within the individual cycles, construction of the high-resolution isochronous stratigraphic framework in the ascending and descending hemicycles of the medium-term cycles and sandstone distribution in the Upper Ganchaigou Formation. It is indicated that the early ascending hemicycles ,late descending hemicycles and the delta system are interpreted to be the most favourahle zones for the development of reservoir sandstones.