贵阳乌当下坝下三叠统大冶组砾屑灰岩特征  

Characteristics of the Calcirudytes of the Early Triassic Daye Formation at Wudang of Guiyang, Guizhou

作　　者：戴新春[1] 

机构地区：[1]贵州工业大学资源工程系

出　　处：《贵州地质》1998年第2期119-135,共17页Guizhou Geology

摘　　要：贵阳乌当下坝一带大冶组砾屑灰岩为层位东高面低，层数东少西多，横向变化明显的不连续楔状体，具有碎屑流沉积特征，代表较大型的水下水道沉积。东西方向变化反映出该地区海底坡向从西高东低转化为东高西低的翘板式变化。文中对砾屑的统计以统计点砾屑灰岩层的层厚为边长的正方形范围作为统计单位，按粒度分级分别统计板条状与粒状砾屑的数量，并对数据进行了方差分析，取得良好效果。The calcirudytes of the early Triassic Daye formation in the Xiaba area atWudang district, Guiyang, are composed of laterally noncontinuous wedges characterized byhighstand deposition corresponding to small numbers of beds to the east, which may reflect a large-sizedebris flow through submarine channels. The field studies of the underlying and overlying strata in thisarea reveal that the deposition seems to have experienced a seesaw-like change in submarinetopography: an initial lowstand deposition eastward followed by the later highstand deposition to the east. Inorder to provide a quantitative evidence for the studies, a statistics of both lath-shaped and granularrudytes per square unit whose side length exactly depends upon the thickness at each measuringlocation is carried out on grain size order, and then variance analyses is done. The results are sacrificedwith the studies.

关 键 词：砾屑灰岩 碎屑流沉积 大冶组 贵阳 乌当下坝 

分 类 号：P588.245[天文地球—岩石学] P588.21[天文地球—地质学]