湘黔交界娄山关组层序地层学研究

传统上认为湘黔交界处的中寒武统一下向陶统娄山关组为均一性极强的厚层白云岩，可分性极差。但笔者新近研究发现，其顶、底均为古岩溶不整合面，并有大量颗粒（鲕、豆、核形石）白支岩和藻纹层白云岩夹层，还有许多鸟眼构造、叠层石横行、交错层帐蓬构造存在。据其重向组合规律，将娄山关组分为三段。认为娄山关组由７个三级层序组成，层序界面为古岩溶不整合面或暴露带，每个序都由海进体系域和高水位体系域构成。

A Study of Sequence Stratigraphy of the Loushanguan Formation in the Boundary Area Between Hunan and Guizhou Provinces

It used to be considered that the Loushanguan Formation was composed of thick-bedded dolomite, which is very difficult for division. However, the authors discovered recently that the top and bottom surfaces of the Loushanguan Formation are palaeokarst unconformity interfaces, and there are a lot of interbeds of granular (oolite, pisolite and oncolite) dolomite and algae-mat dolomite, especially sedimentary structures such as the bird's eye, stromatolite, cross bedding and tepee structures. According to the characteristics of its vertical assemblage, the authors suggest that the Loushanguan Formation could be divided into three sections, and it is made of seven third-order sequences, the boundaries of which are palaeokarst unconformity interfaces or exposed zones. Each sequence is made of transgressive system tracts and highstand system tracts.