辽吉下二台群、呼兰群中昌图动物群的发现及其意义  

DISCOVERY OF THE CHANGTU FAUNA IN THE XIA'ERTAI AND HULAN GROUPS IN LIAONING AND JILIN AND ITS SIGNIFICANCE

作　　者：刘效良[1] 陈从云 杨学增 杨森[1] 张炯飞[1] 高玉华 

机构地区：[1]中国地质科学院沈阳地质矿产研究所

出　　处：《地质学报》1992年第2期182-192,T003,共12页Acta Geologica Sinica

基　　金：地质矿产部行业基金

摘　　要：最近,在辽北—吉中下二台群、呼兰群中,发现了奥陶纪昌图动物群。昌图动物群与早寒武世清河镇动物群有密切的演化关系,化石得10属14种(其中3新属、9新种、2未定种)。昌图动物群的发现,对地层时代,奥陶纪生物地层,以及中朝扳块北侧构造地层地体地质演化研究,具有重要意义。Metamorphosed intermediate-acid volcanic rocks-carbonate rocks named respectively the Xia'ertai and Hulan Groups are developed in northern Liaoning-central Jilin. Their age has been successively referred to asthe Precambrian (Proterozoic), Devonian, Ordovician-Early Silurian, Silurian-Devonian and Cambrian-Ordovician. In 1977, Early Silurian graptolites were found in the black slate from Mengjiagou, Jingjiatai, Yitong county, Jilin province, which was named the Taoshan Formation and since then it has become clear that the ages of the Xiaertai and Hulan Groups might be indirectly settled, but for lack of fossil evidence, no exact dating for the groups can be made, bence searching for fossils is the important task.During 1987—1990, the authors were greatly inspired by finding small shelly fossils from the so-called 'Liache Group-Proterozoic developed in the Qinghe River valley, Kaiyuan county, Liaoning province. Analysing the stratigraphy-tectonics and palaeogeography of the northern Liaomng and cental Jilin region, the authors realized the possibility for the preservation there of the microfossils; then by careful field work small shelly fossils were found from Guanshan, southeast Changtu county. Soon afterward more small shelly fossils (about 500 specimems) were found from 7 localities in Lishu and Panshi counties of Jilin province. All these new finds consitute the Changtu Fauna.The Changtu Fauna is composed of small shells and Gastropoda amounting to 10 genera (3 new), 14 species (9 new) and 2 indetermined species, listed as follows:Cylindricotheca inflata sp. nov., C. bifuraua sp. nov., C. corneola sp. nov., Guanshania annulata gen. et sp. nov., Hyolithellus qingheensis, H. flexa sp. nov., H. voluta sp. nov., Spirellus difformis sp. nov., Changtuella mirabilis gen. et sp. nov., Panshitubulus hulanensis hen. et sp. nov., Cylindrochites daizhuargziensis Archaeooides granulatus, Lophospira sp., Ectomaria sp.The age of the Changtu Fauna is Ordovician based on the following considerations: (1) there are a few com

关 键 词：辽北-吉中 奥陶纪 昌图动物群 地层 

分 类 号：Q915.642[天文地球—古生物学与地层学]