摘要
陕西宁强胡家坝地区新元古界震旦系灯影组出露较好,为一套碳酸盐岩和碎屑岩组合,岩性组合可划分为3段:藻白云岩段、高家山段和碑湾段,其中高家山段风暴沉积发育,为本文研究重点。风暴沉积构造特征在高家山剖面和狮子崖剖面各不相同,高家山剖面丘状交错层理发育,为风暴沉积典型特征;狮子崖剖面碎屑岩沉积可见底面构造、粒序层、水平层理现象等,灰岩层发育水平层理。通过野外实测、室内薄片鉴定等,认为高家山剖面高家山段中部化石层位为海水较浅的近源风暴沉积,而狮子崖相应层位为相对海水较深的远源风暴沉积。
The Neoproterozoic（Sinian） Dengying Formation in Hujiaba region, Ningqiang County, Shaanxi, is exposed well on the outcrops, which belongs to a set of carbonate rocks and detrital rocks. According to the lithological association, it can be divided into three members： algal dolomite Member, Gaojiashan Member and Beiwan Member. The storm deposit of Gaojiashan Member is developed well, which is taken as the key study object in this paper. Sedimentary structures of the storm deposit have differences between Gaojiashan profile and Shiziya profile. The hummocky cross-bedding is developed well in Gaojiashan profile, which belongs to the typical storm deposits. In the detrital rocks of Shiziya profile, there are the obvious sole structures, horizontal beddings, graded beddings etc.; in the limstones of Shiziya profile, there are developed for the parallel beddings. Through field survey and indoor thin-section microscopic identification, it is considered that the fossil-bearing layer of Gaojiashan mid-Member in Gaojiashan profile belongs to the proximal storm deposits of shallow sea, and the corresponding layer in Shiziya profile belongs to distal storm deposit of deep sea.
作者
刘明博
林晋炎
高硒
王晓伟
华洪
徐乔
LIU Mingbo;LIN Jinyan;GAO Xi;WANG Xiaowei;HUA Hong;XU Qiao(State Key Laboratory of Continental Dynamics,and Department of Geology,Northwest University,Xi＇ an,710069)
出处
《城市地质》
2018年第2期57-63,共7页
Urban Geology
基金
国家自然科学基金(NO.41030209)
关键词
灯影组
高家山段
风暴沉积
沉积构造
陕西宁强
Dengying Formation
Gaojiashan Member
Storm deposit
Sedimentary structure
Ningqiang County of Shanxi
