中国天山地质构造理论的几点商榷

DISCUSSION OF THE THEORY OF THE GEOLOGIC TECTONICS IN TIANSHAN MOUNTAINS

80年代初,有的研究者应用日本“沟、谷、盆”系统,根据地球物理资料,提出沿博罗霍洛—阿齐克库都克深大断裂,将天山北半部并入准噶尔—哈萨克斯坦板块(洋壳型),南半部并入塔里木板块(陆壳型),天山不再是一独立的地质构造单元。笔者认为日本东海沟开口处破裂的鹿岛海山。其东半部不仅没有向下俯冲,反而比西半部高出1600m的事实,证明“沟、谷、盆”系统并不符合日本列岛情况,它与博罗霍洛—阿齐克库都克断裂带也不在同一布格重力异常带上,天山仍然是一个重要的地质单元。天山与祁连山、秦岭、桐柏山、大别山、庐沪地区的地质时代衔接,古纬度相近,雁行排列,共同组成巨型古纬向构造带。天山可划分为:中天山火山岩带,南、北天山超基性岩—古老断块褶皱带,天山外缘褶皱带。

To the early 1980's, some of Chinese scholars presented, based on geophysical data and by means of the systemof 'channel, valley and basin' from Japan, that the north half of Tianshan Mountain should be merged along theBoloholo-Achicakuduk deep fractures into Junggar-Kazakstan plate (oceanic crust), the south half of it into Tarimplate (continental crust), and Tianshan Mountain was not an independent geologic-tectonic element any longer. Butthe author thinks that Tianshan Mountain is still an important element, because of the fact that the east half of Ludao-haishan Mountain of Japan had not under-thrusted downward, in contrast, it is 1600 meters higher than the westhalf of it, indicating that the system of 'channel, valley and basin ' is out of accordance with situations of JapanArchipelago, and Boloholo deep fracture was not same as Achicakuduk in Bouguer anomaly. In addition, TianshanMountain's geochronology is linked with that of Qilian Mountain, Qinling Mountain and Dabieshan Mountain as wellas Lu-Hu regions. So,a great paleo-latitudinal structural zone should be formed by them with similar paleo-lati-tude and echelon patterns. It is concluded that Tianshan Mountain can be classified as middle Tianshan volcanic rockzone, south and north Tianshan ultrabasic rock-paleofault block folded zone and Tianshan external margin foldedzone .