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对闽中沿海长乐厚度8m的红土风化壳剖面(CL)间隔5cm采样,进行地球化学元素和粒度组成测试,以OSL与ESR年龄确定年代学框架,据此探讨了1.2Ma以来红土沉积常量化学元素含量、组合及其比值记录的区域气候环境变化特征.结果表明,1.2Ma以来CL剖面第四纪红土风化强度介于红壤型风化壳和赤红壤型风化壳之间变化,表现为中亚热带和南亚热带过渡区红土风化壳特点;早更新世晚期为赤红壤型风化壳向红壤型风化壳转变,反映区域气候由湿热向较暖湿气候过渡;中更新世为红壤型风化壳向赤红壤型风化壳的过渡,反映区域气候由相对暖湿过渡到明显湿热的变化;晚更新世早期发育典型赤红壤型风化壳,区域气候呈现湿热气候特征;晚更新世晚期由湿热向温干转变,早期赤红壤型风化壳有向现代红壤风化壳的逆行演替趋势.CL剖面记录的气候变化特征符合全球气候变化规律,东亚季风系统中夏季风盛衰变迁控制了研究区红土风化壳类型的动态变化.
The geochemical element and grain size composition of the weathered clay crust profile (CL) with a thickness of 8 m in the coastal area of Central Fujian Province was sampled at intervals of 5 cm to determine the geochronology framework based on OSL and ESR ages. Based on this, The results show that the intensity of Quaternary red earth weathering in CL section changed from red soil type to latticed red soil type weathering crust since 1.2 Ma, which was manifested in the middle subtropics and South Asia In the late Early Pleistocene, the weathering crust changed into the red soil weathering crust, reflecting the transition from humid to warm-humid climate in the tropical transitional zone. The mid-Pleistocene weathering red-earth weathered crust to red-red soil weathering Shell transition, reflecting the transition from relatively warm and humid climate to obvious damp-heat; typical Late Red-age weathering crust-type weathering crusts developed in the late Pleistocene, the regional climate showed wet and hot climatic characteristics; late late Pleistocene from warm to dry transition, early red The trend of retrograde succession of red soil weathering crust to the weathering crust of modern red soil is that red soil type weathering crust recorded the climatic change characteristics in line with the global climate change law, Monsoon wind system in summer vicissitudes control the dynamic changes of laterite weathering crust types in the study area.