中国东北地区晚古生代构造-岩浆演化历史

Late Paleozoic tectonic-magmatic evolution history of the northeastern China

中国东北地区位于中亚造山带东段,由多个不同构造属性的微陆块拼贴而成,包括额尔古纳地块、兴安地块、松嫩-张广才岭地块、佳木斯地块以及那丹哈达地体。伴随不同微陆块的复杂拼贴演化过程,东北地区发育强烈的晚古生代岩浆作用,因此这些岩浆作用的产物是记录东北地区晚古生代构造演化历史的重要媒介。根据东北地区晚古生代岩浆岩的岩石学、年代学以及地球化学等特征,发现大兴安岭地区晚古生代岩浆作用以石炭纪-二叠纪为主,其中早石炭世岩浆作用的产物为辉长岩-闪长岩-花岗岩组合,晚石炭世产物以花岗质岩石为主以及少量辉长岩,二叠纪岩浆作用的产物以花岗质岩石为主,同时这些晚古生代岩浆岩大部分具有典型的弧属性特征;而吉黑东部地区则广泛发育的晚古生代岩浆岩,以二叠纪花岗质岩石为主,同时包含少量辉长岩,且这些二叠纪岩浆岩普遍表现出典型的弧属性特征。结合岩石学、年代学、地球化学以及同位素等资料,认为大兴安岭地区和吉黑东部岩石可能具有不同的构造-岩浆演化历史,同时东北地区内各微陆块具有复杂的地壳增生历史。

Northeastern China is suited in the eastern part of the Central Asian Orogenic Belt,and it is mainly composed of Erguna Massif,Xing’an Massif,Songnen-Zhangguangcai Range Massif,Jiamusi Massif,and Nadanhada Terrane.The Late Paleozoic magmatism was relatively intense accompanied with multiple stages of amalgamation in several microcontinents,therefore these magmatic products are an important media in recording the Late Paleozoic tectonic evolution history of the northeastern China.According to the petrological,geochronological,and geochemical characteristics of Late Paleozoic igneous rocks in the northeastern China,we found that the Late Paleozoic magmatism was based on Carboniferous-Permian igneous rocks.The Early Carboniferous magmatic products are gabbro,diorite and granite,the Late Carboniferous magmatic products are mainly composed of granitoids with minor gabbro,and the Permian magmatic products are mainly granitoids.Meanwhile,these Late Paleozoic igneous rocks mostly exhibit typical arc characteristics.In addition,the Late Paleozoic igneous rocks in eastern Jilin and Heilongjiang provinces are mainly Permian granitoids with minor gabbro,and these Permian igneous rocks show typical arc characteristics.Combined with petrological,geochronological,geochemical and isotopic characteristics,we suggest that the Late Paleozoic igneous rocks in the Great Xing’an Range and eastern Jilin and Heilongjiang provinces underwent different magmatic evolution history,and the microcontinents in NE China had different crustal growth history.