中文摘要：

南海北缘及华南沿海在新生代经历了复杂的盆?岭构造演化历史。目前对南海北部大陆边缘的研究大多集中于南海北缘盆地构造演化,而对南海北缘新生代盆?岭构造格局及大陆边缘地貌演化还缺乏完整的认识。盆地沉积物源区示踪和邻区岩体剥露过程的综合对比研究是深入探讨大陆边缘构造和地貌演化的重要途径。文章详细介绍了目前关于盆地沉积物源区示踪和山脉隆升剥蚀过程的主要方法和进展。综合分析南海北缘盆地碎屑沉积物来源及华南沿海主要岩体剥露过程矿物热年代学的已有研究成果,对南海北缘新生代地貌演化及盆地沉积物剥蚀?沉积过程进行了双重约束。华南沿海主要岩体锆石、磷灰石裂变径迹和磷灰石(U-Th)/He热年代学分析结果表明,南海北部大陆边缘演化过程较为复杂,剥蚀过程表现为明显的多阶段性且剥蚀中心由南向北迁移,与典型被动大陆边缘演化有明显的区别。总体上,~25Ma之前的沉积物?Nd值较高、碎屑锆石以年轻颗粒(<500Ma)为主,表明物源以华南沿海地区的中生代花岗岩近源剥蚀为主;而~25Ma之后的沉积物?Nd值较低、前寒武纪碎屑锆石年龄(>500Ma)明显增加,表明物源向华南内陆逐渐迁移。南海北缘盆地沉积物来源由近源向远源的逐渐转变,反映了东亚大陆边缘主要水系,如珠江和闽江等由沿海向内陆的侵蚀扩展过程,这一过程对应于南海的扩张和青藏高原东缘的隆升。

英文摘要：

The continental margin of South China has a long and complex history that dates back to the Mesozoic when it formed part of an active “Andean type” margin associated with north-directed subduction of the Paleo-Pacific Plate. In the Paleocene, the margin experienced significant extension, leading to a complex passive margin. Whilst considerable research effort has been directed at explaining extension across the South China margin, and the age and mechanisms for opening of the South China Sea,relatively little attention has been paid to the impact of these processes on the evolution of the exposed South China continental margin. Coupling between the sedimentation in a basin and the unroofing-erosion in the surrounding orogens makes it possible to understand the basin-mountain evolution, thermo-tectonic history and surface crustal recycling processes by studying the detritus composition, geochemical characteristics of the basin sediments and the timing and rates of exhumation surrounding the orogens.The purpose of this study is to document the timing and rates of exhumation across the Pearl River Mouth region of the South China margin and the provenance of the basins in the northern margin of the South China Sea. Zircon fission track (ZFT), apatite fission track (AFT) and (U-Th)/He thermochronometric data show that the timing and pattern of rock uplift and erosion do not fit conventional passive margin landscape models that require youngest exhumation ages to be concentrated at or close to the rifted margin. The history of South China margin is more complex aided by weakened crust from the active margin period that immediately preceded rifting and opening of the South China Sea. Generally, the higher ?Nd values dominated by Yanshanian (180~67 Ma) zircon grains in sediments deposited prior to 25 Ma indicate the detritus in the northern margin of the South China Sea mainly eroded from Phanerozoic granitic sources exposed in coastal South China. Whereas the lower ?Nd values dominated by the Indosinian (257–205 M