豫西北奥陶系马家沟组碳酸盐岩中裂缝-溶洞的发育特征及成因机制  

Development Characteristics of Fracture-Cave and Their Formation Mechanism in Carbonate Rocks of Ordovician Majiagou Formation in Northwestern Henan Province

作　　者：邵威猛 牛永斌[1] 程梦园 韩科龙[2] 孙凤余[1] 程怡高 荆楚涵 SHAO Weimeng;NIU Yongbin;CHENG Mengyuan;HAN Kelong;SUN Fengyu;CHENG Yigao;JING Chuhan(College of Resource&Environment,Henan Polytechnic University,Jiaozuo,Henan 454003,China;Petroleum Exploration&Production Research Institute,SINOPEC,Beijing 100083,China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454003 [2]中国石化石油勘探开发研究院,北京100083

出　　处：《现代地质》2023年第5期1306-1320,共15页Geoscience

基　　金：国家自然科学基金项目(41102076,41472104,42272178);中国科学院战略性先导科技专项“多尺度、多属性深层碳酸盐岩储层知识库”(XDA14010205)。

摘　　要：豫西北奥陶系马家沟组碳酸盐岩中多发育裂缝和溶洞。在对研究区野外露头实地观测的基础上,利用地质统计学的方法对裂缝和溶洞的发育特征进行研究,并结合区域构造演化特征对其成因机制进行详细分析。研究结果表明:(1)研究区溶洞分为小型溶洞(洞高<1 m)、中型溶洞(洞高1~5 m)、大型溶洞(洞高>5 m)三种类型,以中、小型溶洞为主。(2)依据裂缝-溶洞的发育特征及分布规律,将研究区缝洞型储集空间划分为断控型、层控型和表层岩溶型三种岩溶系统发育模式,其中断控型岩溶系统形成的缝洞发育规模最大。(3)研究区缝洞型储集空间主要形成于古生代与新生代两个时期。构造作用、岩性和水文条件是控制缝洞储集空间发育的最主要因素,其中构造作用对缝洞的空间发育和分布规律影响较大,控制缝洞的发育强度、所处部位和发育方向。岩性及水文条件对缝洞型储集空间的发育程度影响较大,岩石中方解石含量越高,地表径流越丰富,缝洞型储集空间就越发育。本研究提供了一个很好的露头类比对象,对加深理解缝洞型碳酸盐岩储层的成因机制和华北地区煤层底板水的防治具有重要意义。The reservoir space of fracture-caves is well developed in the Ordovician Majiagou Formation carbonate rocks in northwestern Henan Province.Based on observations of local field outcrops,we studied the development characteristics of fracture-caves using geostatistics,and analyzed their formation mechanism in detail in relation to the regional tectonic evolution.The results show that:(1)the local caves can be divided into three types,i.e.small caves(height<1 m),medium caves(height 1-5 m)and large caves(height>5 m),among which medium and small caves predominate;(2)Based on the development characteristics and distribution rules of fracture-caves,fracture-caves can be divided into three development modes,i.e.fault-controlled,strata-controlled and superficial karst-controlled,among which the development scale of the fault-controlled fracture-caves is the largest;(3)The local reservoir space was mainly formed in the Paleozoic and Cenozoic.Tectonics,lithology and hydrological conditions are the most important factors controlling the development of fracture-cave reservoir space,among which tectonics has a greater influence on the spatial development and distribution pattern of fracture-caves,controlling the development intensity,and the location and direction of fracture-caves;lithology and hydrological conditions have also substantial influence on the development degree of fracture-cave reservoir space.The high calcite content in the rocks and the rich surface runoff,the reservoir space of fracture-caves were better developed.This study provides a good outcrop analogy,which is important for the understanding of the genetic mechanism of fracture-cave carbonate reservoirs and prevention and control of coal-bottom water in the North China basin.

关 键 词：裂缝-溶洞 奥陶系 马家沟组 碳酸盐岩 河南省 

分 类 号：P534.42[天文地球—古生物学与地层学]