【作者】 邱殿明；

【导师】 张兴洲； 杨宝俊；

【作者基本信息】 吉林大学 ， 构造地质学， 2005， 博士

【摘要】 论文以佳木斯地块、跃进山岩系、那丹哈达(饶河、完达山)地体为研究重点。通过研究区基础地质和佳木斯微板块内510—530Ma麻粒岩相变质事件和254—270Ma岩浆侵入事件的发现,以及小兴安岭—张广才岭220—200Ma造山后花岗岩,证明佳木斯是一个经历过独立演化过程的外来体,拼合就位时间为254Ma之后,220Ma之前。结合桦南—饶河大地电磁(MT)测深剖面,揭示出佳木斯地块内部及其东界的深部结构状态:佳木斯地块具有完整的大陆岩石圈结构,存在稳定的壳内低阻高导层,位于15km,幔内低阻高导层位于约90km,因此,确认应属微板块。那丹哈达增生地体没有明显的岩石圈底部界限,6— km深度存在不规则的高导层,之上为相互叠置的高阻体和高导体,之下直至60—80km深度的区域,整体上表现为以高导为主,夹有高阻块体。极不规则的电性结构反映出该区是一个极其活动的构造区域,深部的壳幔及岩石圈的调整极不均衡。新生代玄武岩活动强烈也足以证明这一点。那丹哈达地区浅部为逆冲推覆构造,深部为多个增生地体的双层结构。跃进由岩系是佳木斯微板块东缘俯冲与地体增生的产物。并确定佳木斯地块东部的浅部边界和深部不同,同时,也证明佳木斯微板块以东存在过与洋壳俯冲有关的地体增生过程。更多还原

【Abstract】 Abstract: The studied region is located in the east part of Heilongjiang province. Geotectonically, it belongs to the east part of the Central Asian orogenic belt between the North China plate and the Siberia plate, east to the Pacific plate. There exist not only microplate, ophiolite complex, and terrane, representing the evidences of lateral accretional of continent, but also magmatic rock belt and extensional basin-range system, showing evidences of vertical accretion and transformation of continent. The area is a typical place where the structure frames dominated by E-W and S-N trends were reworked by N-E trend structures later. Such three groups of structures reflect the basic structural features on evolution of the continental margin of Northeast Asia , which formed in Paleozoic, early Mesozoic and late Mesozoic respectively. They represent the geodynamical evolutions of Paleo-Asian, Paleo-Pacific, Pacific structural domains respectively. Therefore, this area is an ideal region to study the geodynamic evolution of continental margin of Northeast Asia .The Jiamusi microplate and Nadanhada terrane are two important geological units in the east part of Heilongjiang province. Based on Jiamusi microplate, Yuejinshan rock series and Nadanhada (Raohe, Wandashan) terrane, we selected the deep texture as our topic in order to study the deep texture, structural characteristics of Jiamusi microplate and Nadanhada terrane and their amalgamation from lithosphere scale. Contacting the lateral accretion of continent growth, lithospheric mantle-crust interreaction with vertical accretional process of continental material, combining lithospheric geometry, crustal petrology, structural geology and geochemistry, we built the three-dimensional lithospheric texture and geodynamical process. The general situation of peripheral geological body or marginal convergent belt was introduced in the researching area firstly, i.e. Songnen massif, Xingkai, Xikhote-Aline terrane, Jiayin-Mudanjiang convergent belt, Mudanjiang-Muling convergent belt, Zhangguangcailing granite, North marginal convergent belt of North China plate and so on. After analyzing basic crustal geology of Jiamusi microplate, Yuejinshan rock series and Nadanhada terrane, and collecting isotopic data of recent years, we found an 510~520Ma granulite facies metamorphism and 255~270Ma magmatic intrusion in Jiamusi microplate. Thus it is proved that Jiamusi massif was a foreign microplate which underwent an independent evolution process, and the amalgamation time was late stage of Paleozoic or early stage of Mesozoic.According to the MT deep sounding section of Huanan-Raohe, we understood the lithospheric texture characteristics of Jiamusi massif, Yuejinshan rock series and Nadanhada terrane. And we determined that the boundaries of east part of Jiamusi massif were different in the deep and superficial parts, i. e. the superficial boundary is located 30km to the east of Baoqing and the deep one is under Baoqing. And it suggested that accretional event occurred to the west of Jiamusi micoplate ,which related to oceanic crust.Based on the above analysis, it was suggested that Jiayin-Yilan-Mudanjiang suture between Xiaoxinganling-Zhangguangcailing magmatic belt and Jiamusi microplate was formed in the end of Late Paleozoic to the beginning of Mesozoic, and Tongjiang-Baoqing-Mishan convergent belt between Jiamusi microplate and Nadanhada terrane was formed in late Mesozoic.更多还原