贵州罗甸边阳及紫云城关地区下三迭统碳酸盐岩岩屑流

本文论及的碳酸盐岩岩屑流分布于黔南地区下三迭统罗楼群中,主要发育在Ⅱ、Ⅲ岩性段。碳酸盐岩岩屑流具有以下特征:(1)角砾岩为块状,具有清楚的边界。底面平整或波状,下伏层无碎裂现象。(2)砾石成分复杂,大体可分为两类,一类为斜坡沉积经破碎搬运而来;另一类来自台地或台地边缘沉积。(3)大小混杂,分选磨园均差。(4)角砾岩层呈现粗糙的递变。(5)横向分布有限,但可伸入盆地数公里或10余公里,呈席状、沟槽状或透镜状,被盆地相沉积包围,所以,赋存碳酸盐岩岩屑流的地方,是斜坡坡脚或盆地边缘环境。

LOWER TRIASSIC CARBONATE DEBRIS FLOW IN LUODIAN-BIANYANG-ZIYUN AREA,GUIZHOU

The carbonate debris flow discussed in this paper is distributed prl-warily in lithologic members of Luolou Group of the earlp Triassicsystem in the south of Guizhou province, Its features areThe carbonatebreccias are massive and have clear boundary with a plane or wavy bo-ttom, 2, The composition of the gravels is complex, they may be roughlydivided into two types:slope sediments and platform or platform marginsediments.3.Gravels of various size are mixed，sorting and roundness arepoor, 4.The gradation of the breccia is poor too, Its lateral distribu-tion is limited，it may stretch into the basin several kilometes，sometimeseven more than ten kilometers,having sheet，flute or lens forms，surronud-ed by the basinal sediments, Therefore，the carbonate debris flow surelyexists at the foot of slopes or on basinal margines,