应用化石群落生态学研究分析黄石地区栖霞组沉积环境

QIXIAN SEDIMENTARY ENVIRONMENTS IN HUANGSHI,SOUTHEASTERN HUBEI BASED ON FOSSIL COMMUNITY RECONSTRUCTION

摘要: 湖北省黄石地区栖霞组出露良好,化石丰富,是化石古生态分析的理想地区。通过化石统计、化石形态功能分析、埋藏学分析和围岩沉积学研究,本区栖霞组中共识别出五个化石群落(从下往上):①Crurithyris-Orthotetina(CO)群落;②Schuchertella-Sponge (SS)群落;③Hayasakaia(H)群落;④Sponge (S)群落和⑤Tyloplecta-Paracaninia(TP)群落。化石群落及岩相特点在纵向上和横向上的一致变化,表明本区栖霞组形成于一南高北低的缓坡沉积环境,整个栖霞组为一大的海侵序列构成,各种化石群落和岩相的发展演化均是在这一缓坡沉积背景下形成的。

Abstract: Five fossil communities have been recognized in the Qixia Formation,Huangshi,Hubei based on componental functional morphologic analysis and taphonomic analysis. In ascending order they are. 1) Crurityris-Orthotetina (CO) Community; 2) Sckuchertella-Sponge (SS) Community;3)Hayasakaia (H) Community; 4)Sponge (S) Community,and 5)Tyloplecta-Paracaninia (TP) Community. They belong to Boucot's Benthic Assemblages 2,3 and 4 respectively. The lateral variations in these communities indicate that the formation was accumulated on a carbonate ramp gently dipping northwards on which the Qixian transgressive successions were developed.