碎屑岩储集层成岩流体类型、年代学研究方法及地质应用综述

Review of fluid flow types,chronological methods and geological applications in siliciclastic reservoirs

成岩流体是控制盆地中物质演变与能量交换的重要媒介,与盆地内岩石组成、金属成矿、油气成藏等方面密切相关,具有重要的学术探索意义与实践应用价值。在归纳前人研究成果基础上,结合国内外典型实例研究,对碎屑岩储集层成岩流体类型、年代学研究方法及其地质应用展开综述,最终总结了成岩流体年代学的存在问题与未来展望。总体来看,碎屑岩成岩流体可划分为原生沉积水、大气水、矿物脱水、烃源岩热演化相关流体、深部热液几种主要类型;不同类型成岩流体成分特征与主要影响的成岩阶段有所不同,但普遍会受到包括构造活动、热流事件、沉积作用、输导体系、埋藏过程等多种因素的控制。针对成岩流体年代学研究,作者总结了矿物观察法、流体包裹体、碳酸盐矿物定年法(同位素稀释法、ESR测年法、激光剥蚀原位U-Pb法)、自生伊利石^(40)K/^(40)Ar与^(39)Ar/^(40)Ar定年法、钾长石自生加大^(40)K/^(40)Ar与^(39)Ar/^(40)Ar定年、富有机质沉积物Re-Os定年等分析测试的原理、主要特点、样品要求、适用成岩流体类型等,并归纳了成岩流体年代学在确定地层沉积年龄、恢复成岩流体演化史、确定脆性构造活动时限以及判断油气充注时间等方面的地质应用潜力。

Fluid flow is an important medium controlling material evolution and energy exchange,and is closely related to rock composition,metal mineralization,and hydrocarbon reservoir accumulation in sedimentary basins,and therefore has high significance for exploration and practical application.By summarizing the previous research achievements and combining with the typical case studies,the fluid flow types,chronological methods and geological applications in siliciclastic reservoirs were reviewed.Finally,the existing problems and prospects of diagenetic fluid chronology were summarized.In general,fluid flow of clastic rocks can be classified into several main types:connate water,meteoric water,water from dehydration of minerals,fluid related to thermal evolution of source rocks,and deep hydrothermal fluid.The composition characteristics of different types of fluid flow and the main influencing diagenetic stages vary,but they are generally controlled by a variety of factors including tectonic activity,tectonothermal events,sedimentation,transport systems,and burial history.For diagenetic fluid chronology,the authors summarized the principles,main characteristics,sample requirements,applicable diagenetic fluid types about mineral observation method,fluid inclusion,calcite mineral dating(isotopic dilution method,ESR method,LA-ICP-MS method),authigenic illite^(40)K/^(40)Ar and^(39)Ar/^(40)Ar dating,potassium feldspar overgrowth^(40)K/^(40)Ar and^(39)Ar/^(40)Ar dating,organic-rich sediment Re-Os dating and other analytical techniques.Moreover,the geological application of diagenetic fluid chronology for determining the sedimentary age of strata,recovering the evolutionary history of diagenesis,determining the precise time of brittle tectonic activity,and determining the timing of hydrocarbon charging was summarized.