沉积与特提斯地质
沉積與特提斯地質
침적여특제사지질
SEDIMENTARY GEOLOGY AND TETHYAN GEOLOGY
2014年
1期
95-101
,共7页
黄韶春%龚臣%彭建华%杨志龙%何俊
黃韶春%龔臣%彭建華%楊誌龍%何俊
황소춘%공신%팽건화%양지룡%하준
江让组%上三叠统%角度不整合%印支运动%冈底斯西部%西藏
江讓組%上三疊統%角度不整閤%印支運動%岡底斯西部%西藏
강양조%상삼첩통%각도불정합%인지운동%강저사서부%서장
Jiangrang Formation%Upper Triassic%angular unconformity%Indosinian orogeny%western Gangdise%Xizang
在西藏措勤打加错地区新发现上三叠统江让组,其为一套海相碎屑岩及碳酸盐岩沉积建造,岩性主要为不等厚层状石英质砾岩、深灰色薄层状-块状生物碎屑微晶灰岩、含砂粉砂质微晶灰岩、含石英砾质生物碎屑灰岩、砂屑灰岩夹钙质细砂岩,产珊瑚 Distichophyllia sp.,Volzeia sp.,Montlivaltia sp.,M. cf . xainzaensis 、海绵:Hartmanina sp.和双壳类 Xenocardita ?sp.,时代为晚三叠世卡尼期-诺利期,与下二叠统昂杰组呈角度不整合接触。江让组在该地区的发现,完善了冈底斯西部三叠纪的地层系统,为研究印支运动对冈底斯西部的影响和古特提斯洋的演化提供了依据。
在西藏措勤打加錯地區新髮現上三疊統江讓組,其為一套海相碎屑巖及碳痠鹽巖沉積建造,巖性主要為不等厚層狀石英質礫巖、深灰色薄層狀-塊狀生物碎屑微晶灰巖、含砂粉砂質微晶灰巖、含石英礫質生物碎屑灰巖、砂屑灰巖夾鈣質細砂巖,產珊瑚 Distichophyllia sp.,Volzeia sp.,Montlivaltia sp.,M. cf . xainzaensis 、海綿:Hartmanina sp.和雙殼類 Xenocardita ?sp.,時代為晚三疊世卡尼期-諾利期,與下二疊統昂傑組呈角度不整閤接觸。江讓組在該地區的髮現,完善瞭岡底斯西部三疊紀的地層繫統,為研究印支運動對岡底斯西部的影響和古特提斯洋的縯化提供瞭依據。
재서장조근타가착지구신발현상삼첩통강양조,기위일투해상쇄설암급탄산염암침적건조,암성주요위불등후층상석영질력암、심회색박층상-괴상생물쇄설미정회암、함사분사질미정회암、함석영력질생물쇄설회암、사설회암협개질세사암,산산호 Distichophyllia sp.,Volzeia sp.,Montlivaltia sp.,M. cf . xainzaensis 、해면:Hartmanina sp.화쌍각류 Xenocardita ?sp.,시대위만삼첩세잡니기-낙리기,여하이첩통앙걸조정각도불정합접촉。강양조재해지구적발현,완선료강저사서부삼첩기적지층계통,위연구인지운동대강저사서부적영향화고특제사양적연화제공료의거。
The Upper Triassic Jiangrang Formation newly discovered in the Daggyai Lake area,Coqen,Xizang is built up of a succession of sedimentary formation composed of mixed marine clastic rocks and carbonate rocks. Lithologically,these rocks include bedded quartzose conglomerates,dark grey thin-bedded to massive bioclastic micritic limestones,sand-bearing silty micritic limestones,quartz-bearing gravelly bioclastic limestones and sandy limestones intercalated with calcareous fine-grained sandstones,in which there occur the Carnian-Norian( Late Triassic)organic fossils such as the corals Distichophyllia sp. ,Volzeia sp. ,Montlivaltia sp. and M. cf. xainzaensis ,the sponges Hartmanina sp. ,and the bivalves Xenocardita?sp. . The Jiangrang Formation displays an angular unconformable contact with the Lower Permian Angjie Formation. The discovery of the Jiangrang Formation will improve the Triassic stratigraphic systems in western Gangdise,and may provide the new evidence for the better understanding of the Indosinian movements in western Gangdise and the evolution of the Palaeo-Tethys.