漠河盆地上侏罗统沉积特征与构造背景

对晚侏罗世漠河盆地的沉积特征进行了分析，并探讨了其构造类型和成因机制。详细的沉积学研究表明:晚侏罗世漠河盆地主要发育冲积扇、扇三角洲和湖泊相沉积，属于前陆盆地的陆相磨拉石部分。晚侏罗世漠河盆地的物源来自南北两个方向，具有典型前陆盆地双向物源特点:北部物源区是蒙古-鄂霍茨克造山带，位于西伯利亚板块南缘；南部物源区是下伏板块基底，位于大兴安岭北部。根据沉积特征、区域大地构造背景和俄罗斯上阿穆尔盆地有关资料认为:晚侏罗世漠河盆地为漠河-上阿穆尔前陆盆地的南半部分，形成和演化受蒙古-鄂霍茨克造山带制约；晚侏罗世二十二站期和额木尔河期是漠河盆地的主要成盆期，该时期湖泊面积广阔、暗色泥岩发育，是烃源岩的重要形成期。

Sedimentary Characteristics and Tectonic Setting of the Upper Jurassic Mohe Basin

The authors deals with the sedimentary characteristics of the Late Jurassic Mohe basin, and studies its tectonic type and genetic mechanism. Detailed sedimentary research indicates that Late Jurassic Mohe basin contains the alluvial fan, fan-delta and lacustrine facies,  belonging to continental molasse deposits of the foreland basin. The provenances of the Late Jurassic Mohe basin came both from the southern and northern direction and is characterized by bidirectional provenance of typical foreland basin. The northern provenance was the Mongolia-Okhotsk orogenic belt, lied at the southern margin of the Siberian plate; the southern provenance was the basement of underlying plate, lied at the northern part of the Daxing’anling Mountains. According to sedimentary characteristics, regional tectonic setting and materials of the Upper Amur basin in Russian, the Late Jurassic Mohe basin is considered to be the southern half part of the Mohe-Upper Amur foreland basin, whose formation and evolution were controlled by the Mongolia-Okhotsk orogenic belt. The Er’shi’erzhan and Emuerhe periods were the main basin forming periods for the Mohe basin. Dark mudstones had developed in a wide area during this period, and are good source rocks.