塔里木盆地寒武纪—早奥陶世构造古地理与岩相古地理格局再厘定——基于地震证据的新认识  

Redefinition on Structural Paleogeography and Lithofacies Paleogeography Framework from Cambrian to Early Ordovician in the Tarim Basin:A New Approach Based on Seismic Stratigraphy Evidence

作　　者：陈永权[1] 严威[1] 韩长伟 杨鹏飞[1] 李峥[3] 

机构地区：[1]中国石油塔里木油田分公司,新疆库尔勒841000 [2]中国石油东方地球物理公司勘探开发研究院库尔勒分院,新疆库尔勒841000 [3]中国石油大学地球科学学院,北京102249

出　　处：《天然气地球科学》2015年第10期1831-1843,共13页Natural Gas Geoscience

基　　金：中国石油天然气股份有限公司重大科技攻关专项"塔里木油田勘探开发关键技术研究及应用"(编号:22121G20112001)资助

摘　　要：塔里木盆地下古生界白云岩分布范围广,发育厚度大,生储盖组合配置条件优越,勘探前景广阔。基于二维、三维地震资料的精细解释,结合野外露头与钻井地质资料,准确刻画了下寒武统、中寒武统、上寒武统—中奥陶统的地层厚度与寒武纪—早奥陶世台缘带的迁移与平面分布,并开展了寒武纪—早中奥陶世的构造古地理与岩相古地理研究。研究揭示,塔里木盆地寒武纪—早奥陶世构造古地理表现为南高北低、西高东低的构造古地形地貌,具有一定的继承与演化特征;早中寒武世,塔里木盆地表现为"大隆大凹"的特点,具有南高北低、西高东低的构造古地形地貌特点,构造古地理可划分为南天山洋盆、库满台盆、塔北凸起、满西凹陷、巴楚台坪、塔南隆起、西昆仑洋与罗西凸起8个单元;晚寒武世—早奥陶世,构造古地理格局发生较大变化,阿尔金弧后盆地开始发育,并连接库满台盆与西昆仑洋盆,致使南天山洋—库满台盆—阿尔金弧后盆地与西昆仑洋连为一体,塔西孤立台地才真正形成。塔里木盆地早寒武世为缓坡—古陆—局限台地—开阔台地—台缘—斜坡—深水盆地相模式;中寒武世为缓坡—蒸发台地—台缘—斜坡—盆地相模式;晚寒武世—早奥陶世表现为局限台地—半局限台地—开阔台地—台缘—斜坡—盆地沉积模式;以构造古地理框架为基础,结合地质资料点控制下的沉积模式认识,修编了塔里木盆地寒武系—下奥陶统沉积相图。In the Tarim Basin,dolostone strata widely distribute in the Lower Proterozoic with great explo- ration potential. Based on 2D and 3D seismic materials explanation and geologic materials analysis,the stra- ta residual thickness of the Lower Cambrian, Middle Cambrian, and Upper Cambrian to Lower Ordovician were reconstructed,and the structural paleogeography and the lithofacies paleogeography from Cambrian to Early Ordovician are studied. Structural paleogeography features from Early Cambrian to Middle Cambrian in the Tarim Basin present western-high-eastern-low and southern-high-northern-low characteristics, and can be divided into eight departments, which are southern Tianshan ocean, Kuman Depression, western Kunlun ocean, southern Tarim Uplift, Middle slope, Tabei Uplift, Luoxi Uplift, and Manxi Depression. Be- cause of the formation of back-arc basin at Northern Altyn platform,southern Tianshan oeean,Kuman De- pression,Altyn back-arc basin and western Kunlun ocean were connected together from Late Cambrian to Early Ordovician,leading to the indeed formation of western Tarim isolated platform. Lithofacies paleo-ge- ography features from Cambrian to Early Ordovician demonstrate a framework of platform in the west and basin in the east, and sedimentary patterns evolved from paleoterrene-semirestricted platform open plat- form-edge-slope-basin in Early Cambrian, to evaporated platform-edge-slope-basin in Middle Cambrian, to semi-restricted platform-open platform-edge-slope-basin in Irate Cambrian and Early Ordovician. Sedimen- tary facies maps of Early Cambrian, Middle Cambrian, Late Cambrian and Early Ordovician were modified at last.

关 键 词：塔里木盆地 寒武纪 早奥陶世 构造古地理 岩相古地理 

分 类 号：TE121.3[石油与天然气工程—油气勘探]