华北上石炭统太原组灰岩中的Zoophycos痕迹组构  

Zoophycos ICHNOFABRIC IN LIMESTONES OF TAIYUAN FORMATION,NORTH CHINA

作　　者：胡斌齐永安 

机构地区：[1]焦作工学院,454000

出　　处：《煤田地质与勘探》2000年第1期12-15,共4页Coal Geology & Exploration

摘　　要：应用痕迹组构的分析方法 ,概要论述了华北沉积地层区上石炭统太原组灰岩中的痕迹化石产状特征和痕迹组构的主要组成特征。结合沉积学分析 ,首次提出了五种组构类型 :类型 A—Zoophycos占绝对优势 ,分异度低 ,生物扰动强度为 2级 ,常见于泻湖或水体较宁静的海湾环境 ;类型 B—以 Thalassinoides和 Zoophycos为主 ,分异度和丰度都较高 ,生物扰动强度为 3级 ,属正常天气浪基面和风暴浪基面间的上部沉积环境 ;类型 C—痕迹化石丰度较高 ,常见有 Zoophycos、Tha lassinoides、Planolites、Taenidium、Palaeophycos和 Teichichnus等 ,可分辨出 4个阶梯 ,生物扰动强度为 3～ 4级 ,形成于正常天气浪基面至风暴浪基面间的下部沉积环境 ;类型 D—主要由 Zoophycos和 Chondrites组成 ,丰度高 ,但分异度低 ,生物扰动强度为 5级 ,产生于风暴浪基面附近或较闭塞的环境 ;类型 E—生物扰动极强 ,扰动指数为 2 6 ,偶而可识别出 Zoophycos和 Chondrites,可能属局限河口湾下部或风暴浪基面之下的沉积环境。Occurrence and constitution features of trace fossils in limestones of Taiyuan Formation,Upper Carboniferous, within sedimentary stratum areas,North China,aredemonstrated with ichnofabricanalysismethod.Combined with sedimentation analysis,5 types ofthe ichnofabricarefirstly suggested as follows:Type A Zoophycosbeing dominat,with low differentiation de gree,BI( bioturbation index) =2 ,commonly occurred in lagoon or bay environmets;Type B consisting mainly of Thalassinoides and Zoophycos,being ofhigh differentiation degreeand abundance,BI=3,occurred in upperpartbetween norm wetherwavebase and storm wave base;Type C consisting of Zoophycos,Thalassinoides,Planolites,Taenidium,Palaeophycosand Teichichnusand so on,BI=3～ 4 ,occureed in lower part between norm weather wave base and storm wave base;Type D consisting mainly of Zoophycosand Chondrites,being ofhigh abundence,butlow differentiation degree,BI=5 ,formed near storm wave base or land locked sedimentary environmetnts;Type E being ofstrong bioturbation,BI=2～ 6,a few of Zoophycosand Chondritesmay be oc casionally distinguished in some beds,commonly formed in limitary sedimentary environments such as estuary or environments below storm wave base.

关 键 词：痕迹化石 痕迹组构 灰岩 太原组 华北区 

分 类 号：P588.245[天文地球—岩石学] Q911.33[天文地球—地质学]