From Flysch to Molasse—Sedimentary and Tectonic Evolution of Late Caledonian -Early Hercynian Foreland Basin in North Qilian Mountains  

作　　者：DuYuansheng WangJiasheng HanXin ShiGR 

机构地区：[1]FacultyofEarthSciences,ChinaUniversityofGeosciences,Wuhan430074 [2]SchoolofEcologyandEnvironment,DeakinUniversity,Melbourne,Australia

出　　处：《Journal of China University of Geosciences》2003年第1期1-7,共7页中国地质大学学报（英文版）

基　　金：TheresearchissponsoredbytheNationalNaturalScienceFoundationofChina (No .4 9972 0 78)

摘　　要：The Late Caledonian to Early Hercynian North Qilian orogenic belt in no rthwestern China is an elongate tectonic unit situated between the North China p late in the north and the Qaidam plate in the south. North Qilian started in the latest Proterozoic to Cambrian as a rift basin on the southern margin of North China, and evolved later to an archipelagic ocean and active continental margin during the Ordovician and a foreland basin from Silurian to the Early and Middle Devonian. The Early Silurian flysch and submarine alluvial fan, the Middle to L ate Silurian shallow marine to tidal flat deposits and the Early and Middle Devo nian terrestrial molasse are developed along the corridor Nanshan. The shallowin g upward succession from subabyssal flysch, shallow marine, tidal flat to terre strial molasse and its gradually narrowed regional distribution demonstrate that the foreland basin experienced the transition from flysch stage to molasse stag e during the Silurian and Devonian time.The Late Caledonian to Early Hercynian North Qilian orogenic belt in no rthwestern China is an elongate tectonic unit situated between the North China p late in the north and the Qaidam plate in the south. North Qilian started in the latest Proterozoic to Cambrian as a rift basin on the southern margin of North China, and evolved later to an archipelagic ocean and active continental margin during the Ordovician and a foreland basin from Silurian to the Early and Middle Devonian. The Early Silurian flysch and submarine alluvial fan, the Middle to L ate Silurian shallow marine to tidal flat deposits and the Early and Middle Devo nian terrestrial molasse are developed along the corridor Nanshan. The shallowin g upward succession from subabyssal flysch, shallow marine, tidal flat to terre strial molasse and its gradually narrowed regional distribution demonstrate that the foreland basin experienced the transition from flysch stage to molasse stag e during the Silurian and Devonian time.

关 键 词：North Qilian Mountains Silurian DEVONIAN FLYSCH MOLASSE foreland  basin. 

分 类 号：P548.2[天文地球—构造地质学] P534.4[天文地球—地质学]