【作者】 惠若愚；

【导师】 周瑶琪；

【作者基本信息】 中国石油大学（华东） ， 地质学， 2012， 硕士

【摘要】 我国的中央造山带由西部昆仑-祁连-秦岭段和东部的大别-苏鲁段组成，苏鲁造山带更是位于整个造山带的最东段。作为一条中生代的造山带，苏鲁造山带同时也是一条超高压变质带（UHPM），这是一种代表了深俯冲后折返事件的相带信息，苏鲁地区也因此引起了较广泛的关注和研究。本文在前人研究的基础之上，通过野外现象观察描述、地质图件识别运用等方法，对苏鲁造山带的物质组成、几何形态进行了调查、归纳以及重点剖析，总结出造山带浅部的构造特征；同时，通过对重力资料、航磁资料、大地电磁测深资料、地震层析资料以及深反射地震资料的综合解释与分析，了解苏鲁地区的深部特征信息。在这两方面基础上，对苏鲁造山带深部的动力学过程进行推导，结合古地磁资料，进一步总结出这一地区的造山演化阶段。研究结果表明，造山带发育之前，苏鲁地区的地质背景为：前寒武时期，经历了沉积与岩浆侵入活动的相互交替阶段；古生代时不存在大范围沉积或者侵入事件；晚二叠世至早三叠世时，古特提斯洋北支东段洋壳向华北板块之下进行俯冲，开启了苏鲁造山的序幕。洋壳俯冲结束后，碰撞造山过程开始，相关的动力学过程持续了整个中生代，直到古近纪才正式结束。对整个过程进行阶段性的划分，得到如下五个主要阶段：中三叠世的前期俯冲阶段（即苏鲁俯冲阶段）、晚三叠世的拉张折返阶段、早-中侏罗世的后期俯冲阶段（即扬子俯冲阶段）、晚侏罗世的调整结合阶段以及晚侏罗世-古近纪的伸展减薄阶段。而当造山作用进入尾声后，环太平洋构造域的活动加强，逐渐成为该区构造活动的主控因素，并塑造了造山带的现今复杂的地质面貌。更多还原

【Abstract】 The China’s Central Orogenic Belt consists of western Kunlun-Qilian-Qinling segmentand eastern Dabie-Sulu segment, and Sulu orogenic belt is in the most eastern section. As aMesozoic orogenic belt, the Sulu orogenic belt is also an ultra-high pressuremetamorphic(UHPM) belt, which represents a deep subduction and exhumation. Therefore,the Sulu region has aroused widespread interest and research.Based on previous studies, geological investigation and map reading, this paper analyzesthe composition and geometric formation of Sulu orogenic belt. Then it summarizes thesurface tectonic characteristics of the orogen. At the same time, the paper interpretates thegravity data, areomagentic data, magnetotelluric depth sounding data, seismic tomographicdata and seismic reflection data to understand the characteristic information of the depth.Based on the above analysis, it derives the geodynamical process and sums up the stages oforogenic evolution corroborated by paleomagnetic data at last.The geological background of the Sulu region before the orogenic process can besummarize as follows.First, before the Cambrian period, this region had experiencedinterchangeably stages of deposition and magmatism. Second, there was no deposition orintrusion event in a wide range during the Paleozoic. Third, Late Permian to Early Triassic,the eastern oceanic crust of the North Paleo-Tethys began to subduct down to the North Chinaplate, which opened the prelude of the orogenic time. This time continued throughout theMesozoic, ended at Paleogene. We can divide it into five stages: Early subduction (ie, Sulusubduction) stage during the Middle Triassic, extension and exhumation stage during the LateTriassic, late subduction (ie, Yangtze subduction) stage last form the Early Jurassic to themiddle Jurassic, combination stage during the Late Jurassic and extension and thinning stagefrom the Late Jurassic to the Paleogene period. When orogenesis came to the end, the activities of the circum-Pacific tectonic domain strengthened and became the dominant factorsof tectonic activities in this area, which shaped a complex geological picture of today’s Suluorogenic belt.更多还原