川中磨溪与龙女寺雷口坡组构造特征及油气成藏差异性  

Differences of structure and hydrocarbon accumulation characteristics of Middle Triassic Leikoupo Formation between Moxi structure and Longnvsi structure in Central Sichuan,China

作　　者：孙玮[1] 刘树根[2] 秦川[2] 汪华[3] 李德星[2] 代寒松[2] 

机构地区：[1]成都理工大学地球科学学院 [2]成都理工大学"油气藏地质及开发工程"国家重点实验室,成都610059 [3]中国石油西南油气田公司勘探开发研究院,成都610051

出　　处：《成都理工大学学报（自然科学版）》2009年第6期654-661,共8页Journal of Chengdu University of Technology: Science & Technology Edition

摘　　要：通过对四川盆地中部磨溪和龙女寺地区雷口坡组构造差异性研究,表明现今龙女寺雷口坡组构造较磨溪地区复杂,变形强,切穿雷口坡组的断层发育。印支早期,龙女寺地区构造抬升剥蚀作用强于磨溪地区,大部分地区剥蚀至雷三段,显示为构造高点。之后的构造具有继承性,龙女寺高点持继存在。喜马拉雅期隆升作用对两个地区的影响形成了构造上的差异性。这种差异性与该区古构造和构造位置有一定的联系,更与现今构造复杂化有关。这种构造活动对研究区油气藏的控制作用主要表现为:燕山期,上二叠统生成的天然气垂向运移至雷一1亚段聚集成藏,形成磨溪-龙女寺联合古气藏;喜马拉雅期构造隆升造成两地区构造分异,磨溪地区由于受力较弱,整体抬升过程中气藏未被破坏,形成现今完整的磨溪气田;隆升作用在龙女寺造成较大的构造变动,大的断层切割整个雷口坡组,并成为天然气逸散的通道,雷一段气藏被破坏。Depending on the structural difference between the Moxi structure and Longnvsi structure in the centre of Sichuan Basin,the Longnvsi structure is more complex than Moxi and has stronger deformation and more faults cutting through the Middle Triassic Leikoupo Formation.During early Indo-Chinese epoch,the tectonic movement of uplifting in the Longnvsi area was stronger than that in the Moxi area.At the time,the Longnvsi area was a comparable high point,where the third and fourth sections of Leikoupo Formation were denuded.After that tectonic movement,the Longnvsi structure has inherited the previous structural highness.The effect of uplifting during Himalayan movement has further caused the structural difference between the Moxi structure and Longnvsi structure.The difference relates with paleo-structure and tectonic position,and with tectonic Himalayan movement.The effect of the tectonic movement on oil-gas accumulation in the study area is mainly shown in the following two aspects.（1） During Yanshan period,the gas migrated from Upper Permian through faults vertically into the first section of Leikoupo Formation and formed the Moxi-Longnvsi united paleo-gas pool.（2） The uplifting of Himalayan movement caused the structural difference between the Moxi structure and Longnvsi structure.Because of weak tectonics,the gas in the Moxi area has been preserved,the previous Moxi Leikoupo Formation gas pool was adjusted but not destroyed.However,the Himalayan uplifting in the Longnvsi area is stronger;the faults cut through the whole Leikoupo Formation and were the passages for gas escaping,and made the previous Longnvsi gas pool destroyed.

关 键 词：构造特征 油气成藏 中三叠统 雷口坡组 四川盆地 

分 类 号：TE122.3[石油与天然气工程—油气勘探]