西斜坡区萨二、三油层油气运移特征及对成藏的作用

Oil and gas migration property and its function on reservoir forming of S_(2+3) oil layers in west slope region.

通过油源对比,得知西斜坡区萨二、三油层油气主要来自齐家一古龙凹陷的青山口组和嫩一段。油气运移存在五个主要方向,第一个为古龙凹陷生成的油气经平洋至江桥的运移方向;第二个为古龙凹陷生成的油气经他拉红、白音诺勒至阿拉新的运移方向;第三个为齐家凹陷生成的油气经泰康隆起带的北部至富拉尔基的运移方向;第四个为齐家凹陷生成的油气经泰康至阿拉新的运移方向;第五个为阿拉新至富拉尔基的再运移方向。砂体是油气侧向运移的主要通道,断层起转向、汇聚和沟通作用。油气主要有两期运移,第一期为嫩江组沉积末期,第二期为明水组沉积末期-老第三纪初期。油气运移方向是控制西斜坡区油气成藏与分布的主要因素,只有位于油气运移方向上的那些圈闭聚集油气才是有效的;也是今后西斜坡区萨二、三油层油气勘探的主要目标。

Through oil and source rock correlation, the oil and gas of S2＋3 oil layers in west slope region came from Qingshankou formation （ K1q1 ） and Nen 1 member （ K1n1 ）source rocks in Qijia - Gulong Sag. There were five main migration directions. First was the migration direction of oil and gas generated in Gulong Sagthrough Pingyang to Jiangqiao. Second was the migration direction of oil and gas generated in Gulong Sag through Talahong,Baiyinnuole to Alaxin. Third was the migration direction of oil and gas generated in Qijia Sag through northern Taikang uplift belt to Fulaerji. Fourth was the migration direction of oil and gas generated in Qijia Sag through Taikang to Alaxin. Fifth was the remigration direction of oil and gas from Alaxin to Fulaerji. Sandbody was the main pathway of oil and gas lateral migration.Fault played diverting, gathering and connecting role.There were two main migration periods, the first was the end of K1n sedimentary period, the second was from the end of K2 m sedimentary period to the early of Paleogene sedimentary period. The of oil and gas migration direction is the main factor controlling the accumulation and distribution of oil and gas in the west slope region.The accumulated oil and gas in those traps of the oil and gas migration direction are effective. They are the main exploration targets for oil and gas of S2＋3 oil layers in the west slope region.