上扬子地块黔北坳陷及周缘水文地质-地球化学特征与油气保存  

Hydrogeological-hydrogeochemical characteristics and hydrocarbon preservation conditions of the Qianbei Depression and its periphery,Upper Yangtze Block

作　　者：朱振宏[1] 楼章华[1] 金爱民[1] 张润合 斯春松 姚根顺 

机构地区：[1]浙江大学海洋学院,浙江舟山316021 [2]中国石油杭州地质研究院,浙江杭州310023

出　　处：《石油与天然气地质》2016年第6期862-873,共12页Oil & Gas Geology

基　　金：国家科技重大专项(2011ZX05005-003-008HZ;2011ZX05002-006-003HZ)

摘　　要：从地下水化学-动力学角度对上扬子地块黔北坳陷及周缘油气保存条件进行了研究。结果表明:黔北坳陷及周缘自震旦纪以来共经历了3次重要的水文地质旋回,即加里东期、海西期—印支期和燕山期—喜马拉雅期。黔北坳陷及周缘在加里东期和海西期—印支期是两次主要的油气成藏期,但加里东末期和燕山期—喜马拉雅期运动使得区内原已形成的油气藏几乎被破坏殆尽。多次构造运动和多期大气水下渗作用使得现今黔中隆起埋深小于2 500 m、黔北坳陷埋深小于3 000 m的地层水矿化度低,处于自由交替带且底界尚不清楚,油气保存条件较差;川南坳陷在埋深800 m的浅部地层已进入交替阻滞带,油气保存条件相对较好。The petroleum preservation conditions in the Qianbei depression and its periphery were studied based upon the analysis of groundwater hydrochemical and hydrodynamic characteristics. The results show that the Qianbei depression and its periphery experienced three hydrogeological cycles as follows：Caledonian epoch, Hercynian-Indosinian epoch, and Yanshan-Himalayan epoch. Caledonian epoch and Hercynian-Indosinian epoch are the two main periods of oil-gas reser- voirs deposition, although these reservoirs were eroded almost completely during the period of Caledonian and Yanshan- Himalayan movements. The hydrocarbon preservation conditions of strata less than 2 500 meter depth below surface in the Qianzhong uplift and 3 000 meter depth below surface in the Qianbei depression are generally poor due to the multiple tectonic movements and meteoric water infiltrations. This zone with low mineralization formation water is named as free exchanging zone and its lower boundaries are still unclear. The strata deeper than 800 meter are regarded as an exchan- ging-inactive zone in the Chuannan depression and hydrocarbon preservation conditions thereby are relatively good.

关 键 词：水化学 水动力 油气保存 黔北坳陷及周缘 上扬子地块 

分 类 号：TE133[石油与天然气工程—油气勘探]