陕西金粟山中奥陶统生物扰动构造与古环境分析  

Bioturbation Structures and Paleoenvironment Analysis of the Middle Ordovician at Jinsushan, Shaanxi

作　　者：费安玮[1] 张忠涛[1] 

机构地区：[1]石油大学资源与信息学院,北京102249

出　　处：《地球科学（中国地质大学学报）》2002年第6期703-710,共8页Earth Science-Journal of China University of Geosciences

基　　金：中国石油天然气总公司勘探研究项目"鄂尔多斯盆地天然气勘探新方向和目标评价";石油大学 (北京 )科研基金项目 .

摘　　要：首次在鄂尔多斯盆地南缘陕西金粟山中奥陶统峰峰组八陡段与金粟山组第一段发现遗迹化石及其生物扰动构造 .该地区中奥陶统含大量无法鉴定遗迹属种的生物扰动构造并产丰富的叠层石 .分析、概括了生物扰动构造的分布及其特征 ,采用生物扰动构造半定量分析方法并结合叠层石及沉积学研究对各组段古环境进行了解释 ,进而认为 :中奥陶世自峰峰组八陡段到金粟山组第一段沉积期 ,本区经历了 3次由叠层石发育的潮坪环境到开阔台地浅海低能环境的古地理演变 ,即海平面发生了 3次较大的升降过程 .Trace fossils and bioturbation structures were first discovered from the Middle Ordovician Badou Member of Fengfeng Formation and the Member 1 of Jinsushan Formation at Jinsushan, Shaanxi Province sourthen margin of Ordos basin, where plentiful bioturbation structures are composed of unidentified species and genera and abundant stromatolites. The analysis of the characteristics and distribution of bioturbation structures, with stromatolites and sedimentology research and a method of semi-quantitative analysis for bioturbation structures enabled the authors to explain paleoenvironments of related formations. They suggest that there were three times of paleoenvironmental changes from the stromatolite-developing tidal flat to low energy open platform shallow sea environments, that is, three larger-scale fluctuations of sea level, during the Middle Ordovician Badou Member of Fengfeng Formation to the Member 1 of Jinsushan Formation.

关 键 词：陕西 生物扰动构造 古环境 中奥陶统 金粟山 鄂尔多斯盆地 

分 类 号：P534.42[天文地球—古生物学与地层学]