塔里木盆地塔河地区志留系上倾尖灭圈闭油气成藏

Hydrocarbon accumulation in Silurian updip pinch out traps, Tahe region, Tarim Basin

郭倩 蒲仁海 杨林 孙国峰 朱李 楚宪波

Guo Qian Pu Renhai Yang Lin Sun Guofeng Zhu Li Chu Xianbo

国家大陆动力学重点实验室, 西北大学, 地质学系, 西安, 710069 2. 中国石化, 西北油田分公司研究院, 乌鲁木齐, 830011

State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an, Shaanxi 710069, China 2. Research Institute of Petroleum Exploration & Production, SINOPEC Northwest Company, Urumqi, Xinjiang 830011, China

塔河地区S112-2井于2005年在古生界碎屑岩中获得了高产油流,但由于其位于石炭系与志留系之间的不整合面附近,上下岩性接近,所以油层属于石炭系、东河砂岩还是志留系一直存有争议。该文通过对岩心、测井及地震资料综合研究,确认了S112-2井油藏的时代、构造与圈闭特征,认为该区志留系存在2种砂岩上倾尖灭圈闭:一种是舌状上倾尖灭圈闭,即砂体顶面为单斜,但尖灭线朝北上倾方向呈舌状突出;另一种是鼻凸上倾尖灭圈闭,即尖灭线平直,没有出现向北突出的舌头,但砂体顶面为一个鼻凸构造。后者是在该区发现的可能具有类似含油特征的一种新的圈闭类型。

High-yielding oil flow was found in Paleozoic clastic rocks in Well S112-2 of Tahe region in 2005.The oil flow is on the unconformity interface between Carboniferous and Silurian;hence the origin still remains discussion.Based on core,logging and seismic data,the date,tectonic and trap features of the Well S112-2 reservoir were concluded.2 types of sandstone updip pinch out trap exist in Silurian in the region: a) tongue-shape ones,with monocline at the top of sandbody and pinchout line leading to the north;b) nose-shape ones,with nose-shape structure at the top of sandbody and straight pinchout line.The nose-shape ones are new trap types which may have similar oil-bearing features in the region.

https://doi.org/10.11781/sysydz201102120