胶东半岛早白垩世地壳隆升剥蚀及其动力学意义  

Crust uplift and its implications in the Jiaodong Peninsula,eastern China.

作　　者：张华锋[1] 李胜荣[1] 翟明国[2] 郭敬辉[2] 

机构地区：[1]中国地质大学地质过程与矿产资源国家重点实验室,北京100083 [2]中国科学院地质与地球物理研究所,北京100029

出　　处：《岩石学报》2006年第2期285-295,共11页Acta Petrologica Sinica

基　　金：基金重点项目(40234050);973项目(TG1999075502);中科院创新项目(KZCX1-07)共同资助

摘　　要：地壳大规模的隆升剥蚀通常是重大地质事件的响应,是地球动力学研究的重要内容之一。本文总结了胶东半岛中生代燕山期不同阶段的花岗岩侵位和金矿形成深度并以此估算了胶东半岛地壳隆升-剥蚀的厚度。结果表明胶东半岛在中生代早白垩世140～110Ma期间,地壳隆升-剥蚀厚约7km,而从早白垩末期至今的110Ma以来,地壳隆升-剥蚀厚度不足4km这表明胶东半岛早白垩世140～110Ma期间曾发生了一次重大地质事件,从而导致了胶东半岛整体快速隆升和剥蚀。该事件与中国东部岩石圈减薄的峰期时限耦合,应是岩石圈减薄的深部动力学过程的浅部响应。隆升-剥蚀的深部过程可能与该区造山加厚地壳的拆沉有关,同时还伴有因古太平洋斜向加速俯冲所引起的地幔上涌共同作用有关。Significant crust uplift and erosion are common processes in response to geological crises. Our study on emplacement depth of Mesozoic granites and gold deposition in the Jiaodong Peninsula of eastern China, respectively, indicate that during the early cretaceous from 140 Ma to 110 Ma, crust was uplifted and eroded totally for about 7km, in contrast with no more than 4 km since 110 Ma up to now. The large displacements, Coupled with the lithospheric thinning in eastern China, may be response to delamination of the weakened lower crust which had higher density than that of the sublithosphere after volume of adkitic magma generated, meanwhile, coupled with deep process of mantle upwelling triggered by paleo-pacific subduction in the early Cretaceous.

关 键 词：胶东半岛 早白垩世 地壳隆升剥蚀 拆沉作用 地幔上涌 

分 类 号：P542.1[天文地球—构造地质学] P618.130.2[天文地球—地质学]