摘要:
根据区域构造、古地理和地层资料,中国奥陶纪的诸多板块、地体和活动带应分属11个地理区。文章重点研究了各地理区的边界。这些相邻的地理区块在奥陶纪曾处于远距离分离状态,除华北区南界和华南区北界明显由同期秦岭活动带限定之外,地理区的界线大多只能沿发生在奥陶纪之后的构造拼贴结合带划定,只有塔里木区北界和北疆区南界,得以通过追索代表曾在奥陶纪时段内发育于塔里木板块/哈萨克斯坦中间板块/西伯利亚板块之间的局限洋盆或深海盆地遗迹(即残留缝合带)来予以确定。中国大陆的最终形成经历了从晚石炭世至新生代的长期地质演化过程,主要包括活动带的消减以及板块和地体的漂移、增生与会聚。
Abstract:
Eleven geographic units,corresponding mainly to different allochthonous continental masses(plates and terranes)in the Ordovician in China,are divided on the basis of evidence from regional tectonics,palaeogeography and stratigraphy. The paper is aimed at defining the boundaries of geographic units. Units or regions now in close proximity were distantly separated during the Ordovician. Except for the southern boundary of the North China Region and the northern boundary of the South China Region,which are well demarcated by the coeval intervening Qinling mobile belt,boundaries of most other regions have to be delimited by the conjunctional zones,along which tectonic amalgamations took place after the Ordovician. In detecting boundaries between the Northern Xinjiang/Central TianshanBeishan/ Tarim regions,it is of particular significance to trace the remains of sutural zones that represent the relics of finite ocean basins or deep marine basins,which were developed between the Siberia Plate/Kazakhstan Mid Plate/Tarim Plate during the Ordovician. The final assembly of these Chinese landmasses likely underwent a longsustained process that extended from the Late Carboniferous to the Cenozoic,essentially involving the consumption of the mobile zones and the dispersion,accretion and collision of the relevant plates and terranes.
周志毅 甄勇毅 周志强 袁文伟. 中国奥陶纪地理区划纲要[J]. 古地理学报, 2008, 10(2): 175-182.
Zhou Zhiyi Zhen Yongyi Zhou Zhiqiang Yuan Wenwei. Division of the Ordovician geographic units of China—A synopsis[J]. JOURNAL OF PALAEOGEOGRAPHY, 2008, 10(2): 175-182.