华北地区晚三叠世岩相古地理特征  

Lithofacies paleogeographic characteristics in the Late Triassic in the North China area

作　　者：林玉祥[1] 朱传真 赵承锦[1] 吴玉琛[1] Lin Yuxiang Zhu Chuanzhen Zhao Chengjin Wu Yuchen(College of Geological Science and Engineering, Shandong University of Science and Technology Qingdao 266590, Shandong, Chin)

机构地区：[1]山东科技大学地球科学与工程学院,山东青岛266590

出　　处：《岩性油气藏》2016年第5期82-90,共9页Lithologic Reservoirs

基　　金：国家自然科学基金面上项目"沁水盆地煤层气与致密砂岩气共生成藏机理研究"(编号:41172108);国家油气重大专项"十三五"课题"中深层煤系地层立体勘探有利目标优选"(编号:2016ZX05041005)和"岩性地层油气藏区带;圈闭评价方法与关键技术"(编号:2016ZX05001003)联合资助

摘　　要：由于前人对华北地区晚三叠世岩相古地理的系统研究较少,其沉积格局及演化规律尚不明朗。基于层序地层学理论,根据华北地区上三叠统整体发育特征,将其划分为卡尼阶和诺利—瑞替阶共2个等时地层单元,并以优势相法分别编制了岩相古地理图。晚三叠世华北地区整体上东高西低,地层东薄西厚,以陆相沉积为主。主要沉积区位于鄂尔多斯盆地和南华北地区,前者为开阔的内陆坳陷湖盆,岩相北粗南细,厚度北薄南厚,沉积中心偏南,上三叠统油气资源主要分布于盆地中西部地区;后者由一系列小型湖盆组成,沉积中心位于西北部,以济源地区上三叠统最为发育,其他地区仅为零星分布,储层物性总体较差,上三叠统油气资源匮乏。通过对华北地区晚三叠世岩相古地理的研究,明确了盆地演化、沉积体系、烃源岩、储集层的时空分布规律及其相互关系,认为主要存在自生自储、上生下储和下生上储等3种生储盖组合类型,指出了鄂尔多斯盆地盐定三角洲、环县三角洲、甜水堡三角洲和环县—甘泉地区以及济源盆地为其油气勘探的有利方向。There are few studies on the Late Triassic lithofacies paleogeography in North China, which leads to little understanding of sedimentary pattern and evolution law. Under the guidance of sequence stratigraphy theory,combined with the formation development characteristics, the Upper Triassic in North China area was divided into two isochronous stratigraphic units, Carnian and Norian-Rhaetian, and the lithofacies paleogeographic maps were compiled respectively. During the Late Triassic, the topography of the North China area is lower in the west than that in the east, the stratum is thicker in the west than that in the east, and its sedimentary type is dominated by nonmarine deposits. The main sedimentary area in the North China area is mainly located in the Ordos Basin and the southern North China. The Ordos Basin is an open inland depression based on fluvial-lacustrine clastic sediments, whose lithofacies is coarse in the north and fine in the south, and stratigraphic thickness is thin in the north and thick in the south, so the sedimentary center is near the south, and oil and gas resources of the Upper Triassic are mainly distributed in the central and western areas of the basin. The main sedimentary types in the southern North China are fan delta facies, fluvial facies and shore-shallow lacustrine facies, and the sedimentary center and subsidence center continuously migrated to the northwest. Sedimentary formation is mainly developed in Jiyuan depression and scattered in other areas. Due to the poor reservoir properties, the oil and gas resources of upper Triassic are scarce.The study on lithofacies paleogeographic characteristics of Late Triassic in the North China area reveals the laws of basin evolution, sedimentary system, source rock, reservoir distribution and their mutual relationships in that period. It is considered that the Late Triassic in the North China area mainly exists three types of source-reservoir-cap rock assemblages, including self-source and self-reservoir,up-source and down-reservoir, and

关 键 词：岩相古地理 沉积相 油气勘探方向 上三叠统 华北地区 

分 类 号：TE121.3[石油与天然气工程—油气勘探]