摘要
三叠纪结扎群分布于长江源各拉丹冬地区南北两侧,根据基本层序、沉积环境和层序界面特征,结扎群至少可划分出四个三级层序。沉积古地理格局显示出南浅北深的特点。南部靠近羌塘盆地中央隆起带,陆源物质供应丰富。北部雀莫错一带因远离中央隆起,陆源物质供应相对较少,以泥岩、灰岩为主,生物化石丰富,沉积环境以陆棚为主,在相对稳定的沉积水体中以双壳类、菊石类等生物群得以快速发展。
The Late Triassic Jiezha Group is distributed in the southern and northern sides of Geladandong Mountain.Based on the parasequence types and their superimposed styles,sedimentary environments as well as characteristics of various boundaries,the Jiezha Group have been distinguished at least four depositional sequences in ascending order.The Group was formed in shallow water in the southern side and deep water in northern side.In the southern side next to the middle bulge of Qiangtang basin,the Group is mainly dominated by sandstones because of abundant terrigenous supply,while at Quemocuo of the northern side,because of short of terrigenous supply and rich in fossils such as bivalve and ammonoid,the Group dominated by mudstones and limestones was formed in shelf sea.
出处
《华南地质与矿产》
CAS
2003年第4期66-72,共7页
Geology and Mineral Resources of South China
基金
中国地质调查局区域地质调查项目(200013000092121)
关键词
三叠纪
沉积特征
层序地层
结扎群
Triassic
Jiezha Group
sedimentary characteristics
sequence stratigraphy
Qinghai-Tibet plateau
