邵东保和堂大冶灰岩沉积构造特征

保和堂大冶灰岩中发育丰富的沉积构造,对之研究有助于保和堂、乃至整个湘中的大冶灰岩形成环境的探讨。其第一段岩石发育了丘状波痕、丘状交错层理及粒序层理,是风暴作用的反映;泥裂、水雹痕属于暴露环境。说明大冶灰岩沉积的早期仍属潮上或潮间碳酸盐台地相。中期海水加深,发育了水平层理、变形层理及包卷层理等,近于台地边缘斜坡相。晚期的粒序层理、虫迹等构造,反映了海水再度变浅的趋势。

CHARACTERISTICS OF SEDIMENTARY STRUCTURES OF DAYE FORMATION LIMESTONE IN BAOHETAN,SHAODONG COUNTY

There developed abundant sedimentary structures in Daye Formation limestone in Baohetan, the study of which is helpful for the inquiring to the diagenetic environment of Daye Formation limestone in Baohetan and even in the whole area of central Hunan. The first member of Daye limestone yields hummocky ripple marks, hummocky cross bedding and graded bedding, which are the reflection of storm process. The mud crack and hail imprints, indicating an exposure environment suggest that the early stage of Daye Formation still belongs to supratidal or intertidal carbonate platiform facies. In the middle stage, withe the deepening of the sea water, horizontal bedding, deformation bedding and convolution bedding developed, suggesting a platform-marginal slope facies. The graded bedding, burrow and other structures reflect the trend that the sea water becomes shallowing-up again in the late stage.