河南西峡盆地上白垩统寺沟组遗迹化石及其沉积环境  

TRACE FOSSILS AND SEDIMENTARY ENVIRONMENTS OF THE UPPER CRETACEOUS SIGOU FORMATION IN THE XIXIA BASIN OF HENAN PROVINCE

作　　者：王长征[1] 王海邻[1] 胡斌[1,2] 张利伟[1] 卢旭辉[1] 陈传浩[1] 

机构地区：[1]河南理工大学资源环境学院,河南焦作454000 [2]河南省生物遗迹与成矿过程重点实验室,河南焦作454000

出　　处：《古生物学报》2016年第3期367-384,共18页Acta Palaeontologica Sinica

基　　金：国家自然科学基金项目(41272117;U1204404);河南省生物遗迹与成矿过程重点实验室开放课题(OTMP1402)联合资助

摘　　要：西峡盆地上白垩统寺沟组岩性以紫红色薄层粉砂质泥岩、灰黄—灰绿色厚层状粉砂岩、细砂岩为主,夹灰黄、灰白色厚层状含砾砂岩及中粗砂岩。本次工作发现遗迹化石11属19种:包括Archaeonassaisp.,Arenicolites isp.,Cylindricumisp.,Beaconites antarcticus,B.capronus,B.coronus,Gastruichnus xixiaensis,Naktodemasis isp.,Palaeophycus tubularis,P.heberti,P.sulcatus,P.striatus,Planolites beverleyensis,Planolitesisp.,Scoyenia gracilis,Skolithos verticalis,Skolithos isp,Taenidium irregularis,T.serpentinum和似逃逸迹。根据遗迹化石的产状及其围岩的沉积特征,建立了Beaconites-Palaeophycus遗迹组合和Taenidium-Scoyenia遗迹组合,分别代表了曲流河和浅水湖泊(河漫湖泊)沉积环境中遗迹化石的组成特征。基于岩性特征、沉积构造和遗迹化石组成特征的综合分析,划分出五种沉积序列类型,揭示了寺沟组曲流河边滩、泛滥平原、洪流砂体与河漫湖泊在沉积过程中的变化和相应的遗迹群落变化特征。结合寺沟组中遗迹化石分布及组合特征,Beaconites-Palaeophycus遗迹组合和Taenidium-Scoyenia遗迹组合可归属于Scoyenia遗迹相。The Upper Cretaceous Sigou Formation in the Xixia Basin of Henan Province is predominantly terrestrial clastic deposits. Its lithology is mainly made up of red-violet thin mudstones and muddy siltstones, thick-bedded grayish green siltstones or fine sandstones, and intercalated with greyish white medium-to coarse-grained sandstones or pebbly sandstones. Abundant trace fossils were found in the strata, including Archaeonassa isp. , Arenicolites isp. , Cylindricum isp. , Beaconites antarcticus, B. capronus, B. coronus, Gastruichnus xixiaensis, Naktodemasis isp. , Palaeophycus tubularis, P. heberti, P. suZcatus, P. striatus, PZanoHtes beverleyensis , PZanoHtes isp. , Scoyenia gracilis, Skolithos verticalis , S. isp, Taenidium irregularis, T. serpentinum and Fugichnia. Based on the comprehensive analysis of the lithology,sedimentary structures, sedimentary sequences and trace fossil assemblages of the strata, 5 types of depositional sequences are differentiated and the Sigou Formation is explained to have formed se- quentially from meandering fluvial and then to lake shore and shallow lake environments. In this sedi- mentary setting, two ichnoassemblages are recognized： 1） Beaconites-Palaeophycus ichnoassem- blage occurring in meandering fluvial deposition, most of the trace fossils, in terms of their vertical shape, are supposed to be domichnia; 2） Taenidi- um-Scoyenia ichnoassemblage occurring in shallow pond or lake deposits in the meandering fluvial deposits. They can be classified into assemblages of the Scoyenia ichnofacies. The research results not only may enrich the trace fossil database of terres- trial basins in China and offer new data to complete further the continental ichnofacies model, but also provide evidences to explain the palaeoenvironments in the Xixia Basin of western Henan.

关 键 词：沉积环境 陆相遗迹相 遗迹化石 寺沟组 西峡盆地 

分 类 号：Q911.28[天文地球—古生物学与地层学]