渤海海域太古界变质岩潜山裂缝型储层发育主控因素分析  

Analysis of the Main Controlling Factors of the Fractured Reservoirs Development in the Buried Hills of the Archean Metamorphic Rocks in the Bohai Sea Area

作　　者：王清斌 刘晓健 叶涛 金小燕 冯冲 卢欢 李德郁 郝轶伟 Wang Qingbin;Liu Xiaojian;Ye Tao;Jin Xiaoyan;Feng Chong;Lu Huan;Li Deyu;Hao Yiwei(CNOOC(China)Co.,Ltd.Tianjin Branch,Tianjin 300452,China)

机构地区：[1]中海石油(中国)有限公司天津分公司,天津300452

出　　处：《地球科学》2025年第2期453-465,共13页Earth Science

基　　金：国家“十三五”科技重大专项(No.2016ZX05024003).

摘　　要：近几年,渤中凹陷,辽东湾地区太古界变质岩系陆续发现了多个亿吨级油气田,油气柱高度可超过1000 m,展示了太古界潜山巨大的勘探潜力.研究表明,储层发育程度决定了太古界潜山的油藏规模,而裂缝对储层具有核心控制作用.分析表明,岩性对裂缝储层发育程度有明显影响,黑云母、角闪石等塑性矿物含量高的岩性段储层不发育,长石、石英矿物高含量段裂缝发育.表生期风化淋滤降低了岩石的抗压强度,风化壳内裂缝发育程度和记录的期次都要远高于内幕带;薄片观察和模拟实验表明,发育裂缝的样品虽然裂缝被充填但其抗压强度显著降低,为后期裂缝再活化创造了条件;后期裂缝会选择原来的裂缝带重新活化,黏土矿物,碳酸盐矿物,铁质充填的裂缝更容易受到后期应力、流体的影响再活化.宏观上,印支期逆冲推覆作用是形成裂缝储层的关键期,燕山期和喜山期断裂叠加改造对早期裂缝起到了重要的活化作用,印支期与燕山期、喜山期断裂叠合部位控制了厚层储层的分布.In recent years,multiple billion ton oil and gas fields have been discovered in the Precambrian metamorphic rocks of the Bozhong Depression and Liaodong Bay area,with height of oil and gas column exceeding 1000 m,demonstrating the exploration potential of the Archean buried hills.Research has shown that the degree of reservoir development determines the oil reservoir scale of the Archean buried hill,and fractures plays a key controlling role in the reservoir.The lithology has a significant impact on the development degree of fractured reservoirs,The reservoirs with high content of plastic minerals such as biotite and hornblende are not well-developed,while fractures are developed with high content of feldspar and quartz minerals.The weathering and leaching during the epigenetic stage reduce the compressive strength of rocks,and the degree of crack development and recorded stages in the weathering crust are much higher than those in the inner zone.Experiments and thin section analysis have shown that samples with early developed fractures,although filled with minerals,have significantly reduced compressive strength,laying the foundation for later crack development.The later fractures will choose to reactivate the original crack zone,and fractures filled with clay minerals,carbonate minerals,and iron minerals are more susceptible to reactivation under the influence of later stress and fluid.Macroscopically,the Indosinian period was a critical period for the formation of fractured reservoirs due to thrust and overturning.The superimposed transformation of faults during the Yanshan and Himalayan periods played an important role in activating early fractures.The distribution of thick reservoirs was controlled by the overlapping of faults during the Indosinian,Yanshan,and Himalayan periods.

关 键 词：太古界 变质岩 裂缝 构造应力叠加 储层 渤中凹陷 渤海湾盆地 石油地质 

分 类 号：P618.13[天文地球—矿床学]