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深入的奥陶-志留纪交替期生物地层划分对比使古地理精时研究成为可能.对滇、川、黔、渝4省市、24个县、58条剖面的生物地层、群落古生态和古地理资料的分析表明,晚奥陶世至志留纪早期黔中古陆北缘的海岸带一直处于变动之中:(1)奥陶纪凯迪晚期,本研究区广泛接受五峰组沉积,但五峰晚期黔东北海底出现起伏,个别孤岛露出海面;(2)赫南特早中期,当全球海面大幅下降时,观音桥层仍广泛沉积,黔东北出现少数岛屿;(3)赫南特晚期-鲁丹早期,全球海面大幅上升,黔北南部和黔东北不降反升,隆升速度超过海面上升速度,更多、更大的岛屿浮出海面;(4)志留纪鲁丹晚期,这些岛屿复被海水淹没,普遍发育龙马溪组沉积.奥陶纪-志留纪交界时期,黔中古陆以北海域的东区(黔北南部、黔东北、渝东南)和西区(黔西北、滇东北、川南)在地层发育和古地理格局上发生的重要差异,体现了黔中古陆北缘的升隆与扩展,在时空上与发生在湘鄂西的宜昌上升紧密相连,它们均受华南东部和南部深部大地构造活动的制约.
In-depth comparison of Ordovician-Silurian bio-stratigraphic succession makes it possible to study Paleogeographic precision.According to the results of bio-stratigraphy, community palaeo-ecology and community structure in 58 sections of Yunnan, Sichuan, Guizhou and Chongqing provinces, Analysis of palaeogeographical data shows that the coastal zone between the Late Ordovician and the Early Silurian in the northern margin of the Central Guizhou is in constant flux. (1) In the late Ordovician Kaidi, the study area was widely accepted by the Wufeng Formation. However, in the late Wufeng period, (2) In the early and mid-term of Hernán Tete, when the global sea level dropped sharply, the Guanyin Bridge was still widely deposited and a few islands appeared in northeastern Guizhou; (3) Late Hernantean-Early Ludan , The global sea level rose sharply, and the northern part of Guizhou Province and northeast Guizhou province rose non-descending. The uplift rate surpassed the rising rate of the sea surface. More and larger islands surfaced. (4) In the later period of Silurian Lutan, During the period of Ordovician-Silurian boundary, the eastern area (south of Qianbei, northeast of Guizhou, southeast of Chongqing) and western area (northwest of Guizhou, northeast of Yunnan, south of Sichuan) Important difference in stratigraphic development and paleogeography , Reflecting the northern margin of the Guizhou medieval land or Long and extended in time and space and place in West Hubei Yichang rise are closely linked, they are subject to the east and south of tectonic activity in South Deep constraints.