豫西北奥陶系马家沟组遗迹化石及其沉积环境  

Trace Fossils and Their Sedimentary Environment of Ordovician Majiagou Formation in the North-west of Henan Province

作　　者：牛永斌[1,2] 单婷婷[3] 董小波[1] 周硕[1] 高文秀[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 [3]河南理工大学现代教育中心,河南焦作454000

出　　处：《沉积学报》2015年第2期211-225,共15页Acta Sedimentologica Sinica

基　　金：国家自然科学基金"豫西奥陶系碳酸盐岩中生物遗迹组构与储层改造效应"(批准号:41102076);国家自然科学基金"海相碳酸盐岩储层中增强储集性能遗迹组构的属性表征与制约机制"(批准号:41472104)与"构造与油气资源";教育部重点实验室开放基金"豫西北奥陶系碳酸盐岩储层生物改造机理研究"(编号:TPR-2011-34)联合资助

摘　　要：在豫西北奥陶系马家沟组碳酸盐岩中共识别出三大生态类型的遗迹化石10属17种:1居住迹(Domichnia):Psilonichnus upsilon、Thalassinoides callianassa、Thalassinoides horizontalis、Rhizocorallium jenense;2进食迹(Foidichnia):Chondrites type-1、Chondrites type-2、Chondrites intricatus、Palaeophycus tubularis、Palaeophycus heberti、Planolites montanus、Planolites annularius、Phycodes palmatus;3觅食迹(Pascichnia):Helminthopsis ichnosp.、Helminthopsis abeli、Helminthopsis hieroglyphica、Gordia molassica、Scolicia ichnosp.按其古生态和沉积学特征,可划分出三个遗迹组合:1 Psilonichnus-Thalassinoides遗迹组合,代表局限碳酸盐岩台地内的潮坪环境;2Helminthopsis-Gordia遗迹组合,反映局限碳酸盐岩台地的潟湖或开阔碳酸盐岩台地内的滩间海和台内洼地等低能、静水的沉积环境;3Chondrites-Scolica遗迹组合,指示开阔碳酸盐岩台地内洼地中氧化还原界面附近的沉积环境。综合岩石类型、岩石序列组合、沉积构造、生物化石、遗迹化石或遗迹化石组合,建立了研究区奥陶系马家沟组的沉积模式和垂向沉积演化序列。Trace fossils from Ordovician Majiagou Formation consist of at least 10 ichnogenera and 17 ichnospecies,namely,(1) Domichnia:Psilonichnus upsilon,Thalassinoides callianassa,Thalassinoides horizontalis,Rhizocorallium jenense.(2) Foidichnia:Chondrites type-1,Chondrites type-2,Chondrites intricatus,Palaeophycus tubularis,Palaeophycus heberti,Planolites montanus,Planolites annularius,Phycodes palmatus.(3) Pascichnia:Helminthopsis ichnosp.,Helminthopsis abeli,Helminthopsis hieroglyphica,Gordia molassica,Scolicia ichnosp.According to their palaeoecological and sedimentological features,these trace fossils can be divided into 3 ichnoassemblags,ie,1PsilonichnusThalassinoides ichnoassemblage,forming in tidal sedimentary environment of Restricted carbonate platform,mainly composed of Psilonichnus,Thalassinoides,Helminthopsis.2Helminthopsis-Gordia ichnoassemblage,which is associated with lagoon sedimentary environment of restricted carbonate platform,interbank sea or depression of open carbonate rock platform,mainly composed of Helminthopsis,Gordia,planolites,Palaeophycus,Thalassinoides.3 ChondritesScolica ichnoassemblage,which indicates the depression of open carbonate rock platform near the REDOX interface.Finally,depositional model of the Ordovician Majiagou Group and the vertical sedimentary evolution sequence was established based on integrated rock types,rock sequence,sedimentary structure,fossils with trace fossils or ichnoassemblage.

关 键 词：遗迹化石 遗迹组合 沉积环境 奥陶系 马家沟组 

分 类 号：Q911.28[天文地球—古生物学与地层学]