桂西北天峨地区下石炭统有孔虫带及地层划分

STRATIGRAPHIC DIVISION AND FORAMINIFERA ZONES OF LOWER CARBONIFEROUS IN TIAN'E WESTERN-NORTHERN GUANXI

桂西北天峨地区孤立碳酸盐台地 ,上泥盆统顶部至上石炭统下部有孔虫十分发育 ,可划分 15个有孔虫生物组合带 ,它们是地层划分对比的重要依据。以有孔虫Eoendothyra与Quasiendothyra的灭绝、Bisphaera的大量出现划分泥盆系 /石炭系 ,以Eoparastaffella的出现作为维宪阶的底界 ,以Globivalvulina或Pseudostaffella的出现作为上、下石炭统的划分标志 ,生物分带明显 ,与岩石地层分界吻合或基本一致 。

There are a large number of foraminifera in the top of Upper Devonian the bottom of Lower Carboniferous of shallow water carbonate platform tableland of western-northern Guangxi. 15 assemblage zones have been divided, it is an important basis for stratigraphic division and study of stratigraphic sequence. According to exterminated of Eoendothyra-Quasiendothyra and appeared of Bisphaera, it's classifying the boundary line of Devonian/Carboniferous, Eoparastaffella appears at the bottom of Visean, Globivalvulina or Pseudostaffella which appeared is a sign to classify upper and lower Carboniferous. In short, it is a reasonable boundary line for organism obvious classification and stratigraphic coincidence.