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读了1973年第3期《西北地质科技情报》刊登的“1∶20万地质调查中地层单位的划分和一般工作方法”一文后,其中一段(35页)写道:“未经搬运的藻类和珊瑚化石的根部指向下,……利用化石鉴定时代确定层序,新地层在下为倒转”。我想就此作一点补充。迭层石一个最基本、最重要的生态特征,可指示地层层序,确定地层的顶底面,且不受地质时代的限制。就西南地区来说,如贵州遵义松林震旦系灯影组与四川重庆北碚、江油马角坝的下三迭统飞仙关组和上三迭统天井山组中的迭层石,都具有明显地指示地层上下的意
After reading the article “Division of Stratigraphic Units and General Working Methods in 1: 200,000 Geological Survey” published by Northwestern Geological Science and Technology Information, No. 3, 1973, the first paragraph (35 pages) states: “The untreated algae And the roots of coral fossils point down, ... ... use the fossil identification era to determine the sequence, the new strata under the inversion. ” I would like to make a point about this. One of the most basic and important ecological characteristics of laminated stone can indicate the sequence of stratigraphy and determine the top and bottom of the strata without being limited by the geologic age. For the southwestern region, such as the Sinian Dengying Formation in Songlin, Zunyi, Guizhou, and the sedimentary rocks in the Lower Triassic Feixianguan Formation and Upper Triassic of the Weishan Mountain Formation in Beibei, Chongqing, Beibei, Sichuan Province, Indication of the meaning of the strata