前陆冲断带构造逆冲推覆作用与岩石响应特征--以库车坳陷东部中-下侏罗统为例  

Tectonic thrust nappe activity and sandstone rock response characteristics in foreland thrust belt:A case study of Middle and Lower Jurassic,Kuqa Depression,Tarim Basin

作　　者：张荣虎[1,2] 魏国齐[1] 王珂[1,2] 魏红兴[3] 杨钊 余朝丰 智凤琴 ZHANG RongHu;WEI GuoQi;WANG Ke;WEI HongXing;YANG Zhao;YU ChaoFeng;ZHI FengQin(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100086,China;PetroChina Hangzhou Research Institute of Geology,Hangzhou 310023,China;PetroChina Tarim Oilfield Company,Kurla 841000,China)

机构地区：[1]中国石油天然气股份有限公司勘探开发研究院,北京100086 [2]中国石油天然气股份有限公司杭州地质研究院,杭州310023 [3]中国石油天然气股份有限公司塔里木油田分公司,库尔勒841000

出　　处：《岩石学报》2021年第7期2256-2270,共15页Acta Petrologica Sinica

基　　金：国家科技重大专项(2016ZX05003001-002);国家重点研发计划(2019YFC0605501)联合资助。

摘　　要：构造成岩作用一直是控制盆地深层-超深层、前陆冲断带岩石性质的关键因素,尤其是构造逆冲推覆变形及其对岩石的挤压减孔、破裂造缝和流体改造等作用。为了明确库车坳陷东部中-下侏罗统的岩石构造成岩效应和有利储集性岩石分布,本文基于大量露头实测分析、钻井、地震和测井资料对库车河地区中-下侏罗统开展了构造-岩石响应和有利储层分布预测研究。结果表明:喜山晚期南天山隆起强烈的逆冲推覆活动产生巨大的侧向构造挤压,库车河地区最大有效古应力为60-120MPa,迪北地区为90-120Mpa,吐格尔明地区为60-90MPa。构造挤压岩石成岩效应有4种典型特征:(1)急剧降低基质孔隙度,构造减孔量为8.8%/100MPa;(2)破裂造缝大大增加渗透率,网状裂缝大大提高了岩石的渗透率10-100倍;(3)快速提高地层流体压力值,形成异常高压;(4)加速水-岩相互作用强度,沿缝网系统溶蚀作用增强,局部有利于胶结物发育和富集。构造挤压致使岩石微观结构、宏观非均质性增强,吐格尔明地区中-下侏罗统发育2类规模有利储集性岩石,其中阿合组累计厚度超过200m,吐格尔明背斜北翼致密性岩石孔隙度为6%-10%,南翼岩石孔隙度为15%-20%;克孜勒努尔组-阳霞组发育中-厚层相对优质孔隙性岩石,累计厚度大于150m,孔隙度一般9%-15%。为库车坳陷东部中-下侏罗统多种类型油气藏高效勘探提供重要依据。Tectonic diagenesis of sandstones has always been the key factor to control the reservoir properties in the deep,ultra-deep and thrust zones of foreland basins,especially the tectonic thrust nappe deformation and its effects on the rock such as compression reduction,fracture and fluid transformation,which has also become the core of oil and gas exploration,production and research.In order to clarify the tectonic evolution of the Middle and Lower Jurassic in the eastern Kuqa Depression,the rock effect caused by rock structures and the distribution of favorable rocks,this paper carried out a study on the structure-rock response and the evaluation of favorable zones based on the measured analysis of a large number of outcrops,drilling,seismic and logging data.The results show that the southern Tianshan uplift in the Late Himalayan Period produced a huge lateral tectonic compression,and its maximum effective paleostress was 60-120MPa in Kuqa river area,90-120MPa in Dibei area,and 60-90MPa in Tugerming area,respectively.There are four typical characteristics of the compressive diagenesis effects to the rock structures:(1)the porosity of matrix is sharply reduced,and the structural porosity is 8.8%/100MPa;(2)the fractures greatly increase permeability,and reticular fractures greatly increase rock permeability by 10-100 times;(3)the formation fluid pressure is increased rapidly to form abnormal high pressure;(4)the intensity of water-rock interaction is accelerated,and the dissolution of the system along the seam network is enhanced.As a result of tectonic compression,the microstructure and macroscopic heterogeneity of the rock have been enhanced.Two types of favorable reservoir rocks have developed in the Middle and Lower Jurassic in the Tuguerming area.The accumulative thickness of the rocks in the Ahe Formation is over 200m,and the general porosity is 6%-10%.The medium-thick rocks of the Gezilenur Formation and Yangxia Formation are of relatively high quality,with a cumulative thickness of more than 150m and a genera

关 键 词：库车坳陷 中下侏罗统 逆冲推覆 构造成岩 岩石响应 储层性质 

分 类 号：P534.52[天文地球—古生物学与地层学] P542[天文地球—地质学]