Tectonic migration is common geological process of basin formation and development. However, little is known for tectonic migration on the Western Pacific margins. This paper focuses on the representative regions of East China and its surrounding seas in the Western Pacific domain to discuss Cenozoic tectonic migration and mechanism based on our and previous structural results of the Bohai Bay Basin, South Yellow Sea Basin, East China Sea Shelf Basin and South China Sea Basin and others. The Western Pacific active continental margin is the eastern margin of global convergent system located in the junction among the Eurasia Plate, the Pacific Plate and the India Plate. Under the effects of the India-Eurasia collision and retrogressive or roll-back subduction of the Pacific Plate, the Western Pacific active continental margin has a wide basin-arc-trench system which migrated and jumped eventually seaward and eastward. The migration and jumping are characterized by progressive eastward younging of faulting, sedimentation, depression, termination in and/or within basins, and generation, reservoir, seal, trap, migration and preservation of hydrocarbon and gashydrate. Due to the tectonic migration, the conditions related to hydrocarbon and gashydrate accumulation of East China and its adjacent lands and seas also get younger from west to east, and such a spatio-temporal distribution of Cenozoic hydrocarbon and gashydrate is significant for the oil and gas exploration in East China. Finally, this paper discusses the mechanism of Cenozoic intrabasinal and interbasinal tectonic migration in terms of interplate, intraplate and underplating processes. The migration or jumping mechanism of tectonism-magmatism-basin foramtion-hydrocarbon-gashydrate accumulation is the Late Mesozoic extrusion tectonics and the Cenozoic NW-directed crustal extension, the regional far-field eastward flow of the western asthenosphere due to the India-Eurasia plate collision accompanying with eastern jumping and back-rolling of subduction zones of the Pacific Plate.%构造迁移是盆地发展演化过程中十分普遍的地质现象,但西太平洋地区相关研究程度较低,本文基于近10年来对中国东部海域渤海湾盆地、南黄海盆地、东海陆架盆地和南海盆地等所开展的大量研究工作,并综合前人研究成果,对西太平洋地区中最具有代表性的中国东部及邻近海域的新生代构造迁移特征进行了系统讨论.西太平洋活动大陆边缘位于欧亚、太平洋和印度三大板块的交汇处,占据了全球板块汇聚中心的独特位置,并同时受到印度板块的挤入、太平洋板块的后退式俯冲、台湾造山带的楔入的联合作用,自新生代以来,形成了宽阔的自西向东后退式的沟弧盆体系.中国东部及邻区作为西太平活动大陆边缘的重要组成部分,在这个大地构造背景下,新生代的构造特征总体也表现出自西向东的迁移规律,具体表现在盆地的断裂活动性、沉积作用、断陷的萎缩与消亡等自西向东变新逐步演化,新生代的生、储、盖、圈、运、保六大油气成藏要素也表现出西早东晚、自西向东迁移的特征.这种成藏规律的识别对于中国东部油气、天然气水合物勘探具有非常重要的指导意义.最后,从板缘、板内和板下过程和机制,探讨了盆内和盆间的新生代构造迁移机制,这种构造-岩浆-成盆-成藏等的向洋变新迁移和跃迁是晚中生代以来挤出构造和新生代北西向壳内伸展、印度和欧亚板块碰撞诱发的软流圈向东流动的远程效应及太平洋俯冲带的跃迁式东撤的联合效应.
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