吐哈盆地吐玉克油田油气成藏条件

RESERVOIR FORMED CONDITIONS OF TUYUKE OILFIELD IN TURPAN HAMI BASIN.

吐玉克油田主要由深部稠油油藏组成，原油密度大、粘度高、沥青质含量多、轻质组分少，这些特征与其成藏条件及成藏过程密切相关。通过对吐玉克油田的生、运、储、盖条件和构造演化史的分析认为，吐玉克油田的原油主要来自二叠系源岩，生排烃期是晚三叠世－早侏罗世；储集层为三叠系克拉玛依组；盖层为克拉玛依组上部厚达５０～１７０ｍ的泥岩；圈闭构造为形成于晚三叠世末期的克拉玛依运动，经中－早期燕山运动的继承和发展起来的断背斜－断鼻构造；油气运移期为晚三叠－早侏罗世和晚白垩世两期，且以晚三叠－早侏罗世为主；油气运移通道是鲁克沁构造带的断层和克拉玛依组的高渗透砂层。

Tuyuke oilfield consists of deep heavy oil reservoirs with characteristics of high crude density, high viscosity, high bitumen content and low light component, closely related to the reservoir formed conditions and processes. Based on the analysis of the source rock, reservoir,cap rock, hydrocarbon migration and structural evolution history, it is considered that crude in Tuyuke oilfield is mainly generated from Permian source rock, hydrocarbon generation and expulsion is in Late Triassic Early Jurassic; Karamay formation in Middle Triassic is as its reservoir; mudstone with the thickness of 50～170 m in top of Karamay formation is as caprock; faulted anticline faulted nose structure formed in Karamay movement of the end of Late Triassic, was reformed and developed by Indo China movement and early middle Yanshan movement; hydrocarbon migration occurred in Late Triassic Early Jurassic and Late Cretaceous dominated by the former; and hydrocarbon migration channel is faults in Lukeqin structural belt and high permeability sand layer in Karamay formation.