华北地台东部早奥陶世岩相古地理特征  

Lithofacies Paleogeography Characteristics of Early Ordovician in the Eastern Part of North China Platform

作　　者：林玉祥[1] 赵承锦[1] 朱传真 栾伟娜[1] 吴玉琛[1] 李佳[1] 李秀芹[1] 

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：《地球科学与环境学报》2015年第6期1-9,共9页Journal of Earth Sciences and Environment

基　　金：国家自然科学基金项目(41172108);国家科技重大专项项目(2011ZX05033-04;2011ZX05004-01);中国石油"十二五"科技攻关项目(2011A-0203)

摘　　要：基于层序地层学,将华北地台东部下奥陶统划分为新厂阶和道保湾阶。早奥陶世海水较浅,发育浅海和海岸两种沉积环境,自南往北由古陆边缘沉积区过渡为碳酸盐台地沉积区,局限台地和潮上云坪发育。台地呈"中凹边凸"凹面式隆升,南北升降差异逐渐加大,沉积-沉降中心的延伸方向由东西延展向南北方向发展,显示了多种构造应力综合作用而又存在优势方向的特点。相对海平面继承了寒武纪末期的降低趋势,海退大致自NW向SE,台地衰退,云坪和局限台地向东扩展,开阔台地向北、向东退缩。沉积相南北分区的特点使得岩性分区显著,从台地区到潮坪相区,由灰岩过渡为白云岩。需要注意的是,本区云坪亚相准同生白云岩特别发育,中新生代盆地下奥陶统特别是亮甲山组白云岩发育优质储层。Based on sequence stratigraphy, the Lower Ordovician in the eastern part of North China Platform can be divided into two Ⅲ-type sequences, which belong to Xinchangian stage and Daobaowanian stage, respectively. During Early Ordovician, there are two types of sedimentary environments including shallow sea and coastal deposit environments with shallow sea water. The archicontinent marginal sedimentary transits to carbonate platform sedimentary from south to north, and the restricted platform and supratidal dolomitic flat develop. Due to the tectogenetic inconsistency of platform~ the differential uplift and depression are magnified between the south and the north as well as a continuous regression, moreover, the subsidence-sedimentary center extends from the latitudinal direction to the longitudinal direction. There is comprehensive action of various tectonie stresses and predominant direction. Relative sea level inherits the decrease in the end of Cambrian, and the regression happens from NW to SE. Dolomitie flat and restricted platform expand eastward, thus open platform retreats northward and eastward. The sedimentary facies is divided into south part and north part, so that the partition of lithology is significant, and the limestone transits to dolomite from platform to tidal flat. Specially, the penecontemporaneous dolomite of dolomitic flat subfacies develops, and the dolomite from Liangjiashan Formation of Lower Ordovician can act as high-quality reservoir in Meso-Cenozoic basin.

关 键 词：岩相古地理 层序地层学 早奥陶世 华北地台 油气勘探 有利区 

分 类 号：P531[天文地球—古生物学与地层学]