CAJ | 학술논문

祁连造山带乐都一带上三叠统南营儿组砂岩的主量、微量及稀土元素构造背景主要显示为大洋岛弧和被动大陆边缘。物源主要来自被动大陆边缘和大洋岛弧，被动大陆边缘可能是其物源的主要组成部分。沉积母岩为花岗岩，经历了较强的化学风化过程。沉积物受北部卷入北祁连造山带大陆岛弧和主动大陆边缘物质影响，具被动陆缘和主动陆缘兼具的构造背景。碎屑成分具大陆和造山带双向来源的二元物源供给特点。盆地经历了复理石阶段向磨拉石阶段的转变，属典型前陆盆地。盆地古水体处于缺氧、还原环境，有利于有机质的保存。煤线的存在为煤炭的形成提供了可能，显示较好的找煤前景。
기련조산대악도일대상삼첩통남영인조사암적주량、미량급희토원소구조배경주요현시위대양도호화피동대륙변연。물원주요래자피동대륙변연화대양도호，피동대륙변연가능시기물원적주요조성부분。침적모암위화강암，경력료교강적화학풍화과정。침적물수북부권입북기련조산대대륙도호화주동대륙변연물질영향，구피동륙연화주동륙연겸구적구조배경。쇄설성분구대륙화조산대쌍향래원적이원물원공급특점。분지경력료복리석계단향마랍석계단적전변，속전형전륙분지。분지고수체처우결양、환원배경，유리우유궤질적보존。매선적존재위매탄적형성제공료가능，현시교호적조매전경。
The analysis of major,trace and rare elements of sandstones in the Nanyinger formation of the upper Triassic in Ledu area,Qilian orogenic belt, have been studied by analyzing the detrital minerals.The result s suggest that the tec-tonic setting is oceanic island arc and passive continental margin ,the provenance is oceanic island arc and passive conti-nental margin,while passive continental margin was mainly provenance. Its mother-rock was granite which suffered a strong chemical weathering process.It is the effects of continental island arc and active continental margin material from North-Qilian orogenic belt being involved in deposition process that the sediment has the double tectonic background of passive continental margin and active continental margin,and Clastic constituents shows the dual sources characteristics. It is a typical foreland basin which experienced the stage from flysch stage to molasse stage.Ancient water from the basin was hypoxia, reducing environment which advantageous to the preservation of organic matter.Coal lines exist for the coal formation may be provided shows a excellent coal searching prospect exploration.