Title

ISOTOPIC CHARACTERISTICS OF OIL FILED WATERS FROM ORDOVICIAN OIL ACCUMULATIONS IN TAHE OILFIELD AND ITS GEOLOGICAL SIGNIFICANCES

作者

贾存善马旭杰饶丹高仁祥

Authors

Jia Cunshan Ma Xujie Rao Dan Gao Renxiang

单位

中国矿业大学, 资源与安全工程学院, 北京, 100083 2. 中国石油化工股份有限公司, 石油勘探开发研究院无锡石油地质研究所, 江苏, 无锡, 214151 3. 中国石化, 西北分公司, 勘探开发研究院, 乌鲁木齐, 830011

Organization

College of Resource & Safety Engineering, China University of Mining & Technology, Beijing 100083, China 2. Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214151, China 3. Exploration & Production Research Institute of Northwest Branch Company, SINOPEC, Urumqi, Xingjiang 830011, China

摘要

塔河油田奥陶系地层水的δD(SMOW)分布于-44.7‰~-61.0‰,表明为古大气降水和原生沉积水的混合水,并以古大气水为主。根据油田水的高压物性参数、HCO3-离子碳同位素、锶同位素87Sr/86Sr比值等的横向变化规律,大致判断出塔里木盆地阿克库勒凸起古大气水的优势流动方向为从阿克库勒凸起的东北构造高地向鼻凸倾伏的西南方向流动,并且在此流动过程中由构造轴部向两翼分流,通过对断裂、裂隙等薄弱带的不断溶蚀扩大,最终形成塔河油田奥陶系复杂的碳酸盐岩岩溶缝洞系统,为油气聚集成藏提供了有效的储集空间。因此,古大气水流动的方向对岩溶缝洞系统的分布以及缝洞单元的连通性具有重要的控制作用。

Abstract

Hydrogen isotope values(δD) of oil field waters from the Ordovician oil accumulations in Tahe oilfield cover -44.7‰～-61.0‰(SMOW),from which one can conclude that the oilfield waters are mostly paleo-atmospheric waters mixed with original sediment seawater.Based on the transverse change trends of the parameters in these oilfield waters,such as high pressure physical parameter,carbon isotope of CO3- electronegative ion and 87Sr/86Sr ratio of strontium isotope,one can roughly deduce that the predominant flow direction of paleo-atmospheric water is from the northeastern tectonic high position to the southwestern plunge end of the Arkekule nose salient.In this process,the current flowed from axis to two wings of the tectonic,which would cut through weakness belt of faults or cracks and enlarge the space by carbonates corrosion,finally formed complicated karst fracture-cavity system of the Ordovician carbonates in Tahe Oilfield.Therefore,the flow direction of paleo-atmospheric water controled the distribution of fracture-cavity system and connectivity of fracture-cavity cells.

关键词：

岩溶缝洞系统; 同位素; 油田水; 奥陶系; 塔河油田; 塔里木盆地;

Keywords:

Karst fracture-cavity system; isotope; oil field water; the Ordovician; Tahe Oilfield; the Tarim Basin;

基金项目

DOI

https://doi.org/10.11781/sysydz200703292

塔河油田奥陶系油田水同位素特征及地质意义