吉林省东部的大地构造环境与构造演化轮廓

本文运用活动论思维,根据东亚构造发展的宏观背景重新认识吉林省东部地区的大地构造环境与构造演化史。阐明吉林省东部在不同时期所处大地构造环境的变化及由此所决定的不同构造阶段所表现的不同构造属性与特征,为中、新生代以来该区所发生的岩浆活动、变质作用及成矿作用提供时空背景。 本文强调了中生代以来巨大的构造改造对于塑造现今裸露地表的综合地质体面貌的重要意义。忽视它的影响就有可能把许多原本是中、新生代构造运动的产物误认为是前寒武纪就有的古构造,把复杂问题简单化,甚至导致谬误的结论。

GEOTECTONICS AND TECTONIC EVOLUTION OF EASTERN JILIN PROVINCE

The geotectonics and tectonic evolution of eastern Jilin province are reknownby using the mobilism theory, which must involve the recognization of macroscopicbackground for the eastern China and eastern Asia, and have to rethink and-reexamine some concepts and results proposed after 1950' s, to change the thinkingmode of fixism to that of mobilism, as well as to divide the tectonic unit andsummarize the tectonic evolution based on tectonic setting of different stages.In the Indosinian stage, eastern Jilin was situated at the eastern collisionzone and with its south side between the southern Buleyin-Jiamusi block andthe northern Sino-Korea paleoplate. Due to the A-subduction, the north-southtrending collision of paleoplate was intensified in early-middle Jurassic, whichformed a macrosonpic thrust orogeoic zone with the Huifahe fault as its front,which scope is comparable with the recent Himalayan nappe orogenic zone. Fromthe late Jurassic to early Cretaceous, owing to be influenced by the sinistralstrike-slip fault system of western Pacific ocean and the subduction of Kulaocean crust plate, the Helong and. Longgang strike-slip thrust and some amalga-mative terranes were formed. The late Cretaceous Palaeogene was a prosperousperiod for the developing of Yitong-shulan and Dunhua-Mishan rift system.From the end of Palaeogene to Pleistocene, the rift system was sealed bycompression, in which many areas were uplifted through fault-blocking and wereeroded, so as to the tens of thousands deep buried geological body exposed. Thehigh grade metamorphism rock series and ductile shear zone expose widely insouthern Jilin province. Most of them are parts of the Precambrian metamorphicbasements, while a considerable part of them shows the character of deep levelflow-plastic deformation and magmatization of Mesozoic. So that, if we do notconsider the intense deformation since Mesozoic, then it will be all misunder-standed as the Precambrian tectonic and with the result that the problem willbe complicated.