Title

Pyrite-shale interaction in shale gas enrichment and development

单位

(1.西南石油大学石油与天然气工程学院,四川成都610500;2.油气藏地质及开发工程国家重点实验室,四川成都610500;3.中国石油化工股份有限公司石油物探技术研究院,江苏南京211103;4.大港油田公司第三采油厂,天津300380)

Organization

(1.School of Oil & Natural Gas Engineering,Southwest Petroleum University,Chengdu 610500,China;2.State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu 610500,China;3.Sinopec Geophysical Research Institute,Nanjing 211103,China;4.Dagang Oilfield Company,Tianjin 300380,China)

摘要

黄铁矿广泛分布于页岩层中,是一种影响页岩气勘探开发的重要细粒矿物。首先分析了黄铁矿的形成环境及其在页岩层中的特征模式,揭示了黄铁矿的形成机理,并借此实现了对优质页岩沉积带的判别;然后讨论了黄铁矿对页岩气生成过程的催化作用,据此提出了页岩气富集区预测的基本思路及技术方法;最后阐述了黄铁矿增脆作用对于页岩气开发有利区评价的指导意义,同时总结了利用黄铁矿易氧化的特性改造页岩层、达到增渗增产效果的技术方法。研究获得以下认识:黄铁矿与页岩的相互作用有利于优质页岩沉积带、页岩气富集区、页岩开发有利区的预测。

Abstract

Pyrite,which is a fine-grained mineral widely distributed in shale gas reservoirs,has significant effects on shale gas exploration and development.First,depositional environments of pyrite and its characteristic pattern in shale are analyzed,and the formation mechanism of pyrite is revealed,which can lead to the discrimination of high-quality shale sedimentary zones.Furthermore,the hydrocarbon generation mechanism of pyrite is discussed,and then methods to predict the shale gas enrichment zone are proposed.Finally,the beneficial contribution of the brittleness-enhanced characteristic of pyrite to search for favorable mining blocks is expounded.Simultaneously,techniques for reforming shale gas reservoirs by using the easily oxidized characteristic of pyrite to achieve enhanced permeability and increased production are summarized.The results show that pyrit-shale interaction is conducive to the prediction of high-quality shale sediment zones,shale gas enrichment zones,and favorable mining blocks.

关键词：

页岩气; 黄铁矿; 沉积环境; 催化生烃作用; 开发有利区;

Keywords:

shale gas,; pyrite,depositional environment,; catalysis and hydrocarbon generation mechanism,; favorable mining block;

基金项目

国家重点基础研究发展计划(973计划)项目(2014CB239201)与国家科技重大专项(2017ZX05035003)联合资助。

DOI

10.3969/j.issn.1000-1441.2018.03.002

黄铁矿与页岩的相互作用及其对页岩气富集与开发的意义