珠江口全新世沉积物粒度与磁化率的变化特征及其所反映的气候环境变化

HOLOCENEEDIMENTS OF THE PEARL RIVER ESTUARY CHANGES IN GRAIN SIZE AND MAGNETIC SUSCEPTIBILITY AND AS REFLECTED IN CLIMATE CHANGES

通过对来自珠江口万顷沙W2孔的沉积物进行AMS 14 C测年,结合古地磁测试以及孢粉分析结果,并与其他相关记录综合对比,建立了该地区全新世以来的年代框架。使用粒度组合特征以及磁化率等环境代用指标,获取了该地区约6000cal yr BP以来的气候环境变化信息。经过分析与对比,认为该区自中全新世以来,经历了暖干-凉湿-温湿3个气候环境变化阶段。在晚全新世中国南方地区气候(尤其是降雨量)发生了重要的变化,这与北半球太阳辐射减弱,气温降低,亚洲季风减弱,降雨带南移有着一致的对应关系,同时还很可能与这一时期厄尔尼诺—南方涛动活动加强有着紧密的联系。

Through the Pearl River Estuary Wanqingsha W2 core AMS ^[14]C dating of sedi- ments, combined with paleomagnetic test, pollen analysis, and comprehensive comparison with other relevant records, the establishment of the regional framework of Holocene age. Using the combined feature grain size and magnetic susceptibility proxies for the environ- ment, access to climate change information in the area since about 6000cal yr BP. The result show the area since the middle Holocene has experienced in the three stages climate changes of warm and dry-cool and wet-temperature and humidity. South China in the late Holocene climate （especially rainfall） has important changes, corresponding to reduced the Northern Hemisphere solar radiation, air temperature decreased, weakening Asian monsoon, close ties with activities to strengthen E1 Nino-Southern Oscillation events.