松辽盆地北部青一段泥岩超压及意义  

K_1QN_1 MUDSTONE OVERPRESSURE IN NORTH SONGLIAO BASIN AND ITS SIGNIFICANCE

作　　者：姜龙[1] 张秀云[2] 马晓红[3] 

机构地区：[1]大庆油田有限责任公司采气分公司,黑龙江大庆163453 [2]大庆油田有限责任公司第八采油厂,黑龙江大庆163514 [3]吉林油田公司新木采油厂,吉林松原131106

出　　处：《大庆石油地质与开发》2013年第3期25-28,共4页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家重点基础研究项目"天然气高效运移输导网络物理模拟及地质模式"(2001CB209104)

摘　　要：利用声波时差资料,对松辽盆地北部青一段泥岩超压形成及演化过程进行了定量研究,发现其目前普遍存在超压,高值区分布在齐家一古龙和三肇凹陷中心处,最大值可达到12 MPa以上。主要形成于嫩四段沉积时期,之后超压值逐渐增大,在嫩江组沉积末期、明水组沉积末期和古近系沉积末期曾因T_2断裂活动释放,超压值降低。通过青一段泥岩超压形成及演化过程研究可以得到4点石油地质意义:①确定出青一段源岩主要排烃期为明水组沉积末期;②青一段源岩排出的油气向下"倒灌"运移距离最大可达350 m以上,在大庆长垣、三肇凹陷和齐家一古龙凹陷等大部分地区可"倒灌"运移进入扶余油层,进入杨大城子油层的范围略小于进入扶余油层的范围;③超压形成时期早于大量排烃期,对于封闭其油气是有利的;④青一段泥岩超压自形成后,虽在嫩江组沉积末、明水组沉积末和古近系沉积末曾发生释放超压降低,但封闭能力逐渐增强至今。Formation and evolution characteristics of KlqnI mudstone overpressure in North Songliao Basin are quantitatively studied by acoustic logging data. It is considered that the overpressure is universally developed in North Songliao Basin at present; The high-value area of the overpressure distributes in the center of Qijia-Gulong and Sanzhao sags; the maximum value can reach more than 12 MPa. The overpressure was mainly formed in Kin4 sedimentary period and then increased gradually ; because of the activity of T2 faults, the overpressure released and decreased in the end of Kin, KEm and E sedimentary period. By means of the researches on the formation and evolution process of the overpressure, four following petroleum significances are obtained ： ①the main hydrocarbon expulsion phase of K1 qnI source rock was the end of K2m sedimentary period; ②the longest distance of the migration downward of oil and gas from Klqn1 source rock is up to about 350 m. In most parts of Daqing Plaeanticline,Sanzhao and Qijia-Gulong Sags ere, the oil and gas could migrate downward into Fuyu oil layer. The area that oil and gas migrated downward into Yangdachengzi oil layer was smaller than that into Fuyu oil layer; ③Formation period of the overpressure was earlier than the main hydrocarbon expulsion period, that was favorable ior sealing the oil and gas; ④After the overpressure formation for K1qn mudstone, although tile overpressure ever released and decreased in the period stated above, its seal ability has still gradually increased up to now.

关 键 词：松辽盆地北部 青一段泥岩 超压形成 超压释放 断裂活动 

分 类 号：TE122[石油与天然气工程—油气勘探]