黔中—渝南铝土矿含矿岩系时代探讨

A tentative discussion on the age of bauxite-bearing rock series in Central Guizhou-Southern Chongqing area

通过对黔中—黔北—渝南铝土矿含矿岩系9条代表性剖面岩石地层的描述,根据区内石炭系九架炉组、大竹园组和中二叠统梁山组大量孢粉属种的详细统计,结合前人研究成果及其他地质特征,论述了黔中清镇、修文到遵义一带九架炉组形成时代为早石炭世大塘期早—中期,黔北—渝南一带大竹园组形成时代为晚石炭世马平期早期。

Bauxite has been discovered since 1940＇s in Guizhou, and the emphasis of the study have been placed on the generation age of bauxite-bearing rock series. In this paper, a lithographic description of central Guizhou-northern Guizhou-southern Chongqing area was given on the basis of nine standard sections of bauxite-bearing rock series, and a detailed statistic analysis was made for sporo-poUen genera and species widely distributed in Carboniferous Jiujialu Formation and Dazhuyuan Formation and middle Permian Liangshan Formation. Based on data available and related geological characteristics, the authors hold that the age of Jiujialu Formation in Qingzhen and Xiuwen of central Guizhou to Zunyi area and their vicinities belongs to early- middle Datang period of early Carboniferous, and Dazhuyuan Formation in northern Guizhou-southern Chongqing area should be early Maping period of late Carboniferous.