准噶尔盆地南缘古近系-新近系异常高压系统与油气成藏机理

运用钻井压力监测、电缆测试实测压力和声波时差等资料 ,对准噶尔盆地南缘古近系新近系中普遍存在的异常高压地层进行了识别。研究结果表明 ,研究区存在滞排型和顶封滞排型两种异常高压系统 ,其中欠压实作用、封隔层封闭作用和构造抬升作用是异常高压系统的主要成因 ;同时认为异常高压对该地区油气成藏具有控制作用。准噶尔盆地南缘呼图壁地区的滞排型异常高压系统有益于气藏的形成和保存 ;独山子异常高压系统只对超压系统形成之前和同期运移来的油气起封隔和保存作用 ,而对后期的油气向系统内运移起阻止作用 ,从而影响油气聚集

Overpressure and mechanisms of hydrocarbon accumulation in Tertiary of southern Junggar Basin

By the use of drilling pressure monitoring data, pressure and interval transit time measured with wireline test, the abnormal overpressure widely developed in the Tertiary of the southern Junggar Basin was identified. The overpressure systems in the worked area can be divided into two types, which were mainly caused by disquilibrium compaction, sealing and tectonic uplift. The abnormal overpressure had a significant control on hydrocarbon accumulation. The overpressure system in Hutubi area of Junggar was benefit for the formation and conservation of gas pools. However, the overpressure system in Dushanzi area was only benefit for the seal and preservation of oil and gas migrated in the same period or before the formation of overpressure system and had a resistance to the later migration of oil and gas towards the overpressure system.