陆相湖盆三角洲—滩坝复合砂体分布模式及编图方法  

Distributing pattern and mapping method of delta and beach-bar composite sand-bodies in continental lacustrine basin

作　　者：纪友亮[1,2] 刘君龙[1,2] 王天云[1,2] 刘大卫[1,2] 程同冉 

机构地区：[1]中国石油大学(北京)地球科学学院,北京102249 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249

出　　处：《古地理学报》2016年第4期615-630,共16页Journal of Palaeogeography：Chinese Edition

基　　金：国家自然科学基金项目(编号:41272157);中国石油科技创新基金项目(编号:2014D-5006-0101);中国石油大学(北京)科研基金项目(编号:2462013YJRC038;2462015YQ0108);国家科技重大专项(编号:2011ZX05003-002)联合资助~~

摘　　要：陆相湖盆与海洋环境不同,具有水体浅、能量弱、湖进湖退频繁等特点。综合应用高精度层序地层学和地震沉积学等关键技术,通过中国东部及中西部典型陆相湖盆的勘探实践、野外露头解剖和现代沉积考察,总结了陆相湖盆三角洲—滩坝复合砂体的分布模式,并提出了复合砂体地质编图法。研究结果表明:(1)陆相湖盆的"湖—陆过渡沉积体系"不仅发育分流河道,还发育河口坝和沿岸砂坝,这些不同时期的分流河道、河口坝和沿岸砂坝交织叠加在一起,在古代地层和现代沉积中得以保存;(2)地形平坦处,水体浅、波浪作用不强、河流作用为主,形成河道砂体;湖岸较陡处,波浪作用强,分流河道砂体被波浪改造,形成沿湖岸分布的滩坝砂体;(3)在高频湖平面变化背景下,岸线的迁移导致沉积坡折的迁移,形成了多期垂直于岸线分布的树枝状三角洲分流河道砂体,和多期平行于岸线呈带状分布的沿岸滩坝砂体相互交织的陆相湖盆三角洲—滩坝复合砂体的特殊结构;(4)复合砂体地质编图法基于传统单因素法,以复合砂体分布模式为指导,主要针对发育在水体较浅、地形平坦开阔背景下的陆相湖盆三角洲—滩坝砂体。The continental lacustrine basin,which is different from marine environment,has the characteristics of shallow-water,low-energy,frequent progression and regression,etc.Based on key tech-nologies of high-resolution sequence stratigraphy and seismic sedimentology,combined with the explora-tion practice,analysis of outcrops and investigation of modern sediments of the typical continental lacus-trine basins in eastern and central-western regions of China,we summarized the distribution pattern of delta and beach-bar composite sand-bodies in the continental lacustrine basin and proposed the geological map-ping method of composite sand-bodies.The results show that：（1 ）The “lacustrine-continental transitional sedimentary system”in continental lacustrine basins,not only has tributary channels,but also has channel mouth bars and longshore bars,sediments of tributary channels,channel-mouth bars and longshore bars in different geological times were superimposed and preserved in ancient strata and modern sediments;（2）In the condition of flat-terrain,shallow-water and low-energy wave regime,the fluvial process is predominated and channel sand-bodies were formed;in the condition of steep-terrain and high-energy wave regime,the sand-bodies of tributary channel were reformed and the beach-bar sand-bodies along the lake shore were formed;（3）In the background of high frequent lake level changes,the migration of sedimentary slop-break was dominated by the migration of shoreline,and the special structure of composite delta and beach-bar sand-bodies,which were superposed by the multi-period dendritic distributary channel sand-bodies perpendicular to the coast,and the multi-period banding beach-bar sand-bodies along the shore in conti-nental lacustrine basin,was formed;（4）Based on the distribution pattern of composite sand-bodies,the geological mapping method of composite sand-bodies is derived from traditional single factor method,and it mainly focused on the delta and beach-bar sand-bodies that developed in cont

关 键 词：陆相湖盆 三角洲 滩坝 砂体叠置模式 控制因素 编图方法 

分 类 号：P512.2[天文地球—地质学]