摘要
以泰国湾T155号柱状沉积物为研究对象,利用地球化学和矿物学手段探讨了全新世以来泰国湾古气候演化历史。(La/Sm)_(UCC)-(Gd/Yb)_(UCC)指示了全新世以来泰国湾西南部物质来源较为稳定,主要来自于马来半岛,季风控制下的沿岸流是其主要驱动力。通过对高岭石/(绿泥石+伊利石)(ω_(k)/(ω_(c)+ω_(l)))、化学蚀变指数(CIA)和钾铝质量分数比值(ω_(K)/ω_(Al))的变化规律进行综合研究,将全新世以来泰国湾古气候演化过程划分为两个阶段:①早中全新世(12000~6500 cal a BP):ω_(k)/(ω_(c)+ω_(l))值和CIA值较高,ω_(K)/ω_(Al)值则较低,指示了该段时期强盛的东亚季风;发生于11200~10500 cal a BP和8500~7500 cal a BP的冷事件指示了泰国湾对新仙女木事件和8.2 ka冷事件的响应;②中全新世(6500 cal a BP)以来:ω_(k)/(ω_(c)+ω_(l))值和CIA值明显下降,ω_(K)/ω_(Al)值则逐渐上升,指示了该段时间东亚季风呈逐渐减弱的趋势;在3200~1800 cal a BP时地球化学和黏土矿物指标呈现一个明显低值,对应于热带海域“斜氏普林虫低值事件”,揭示了全球气候变化在泰国湾海域良好的区域性响应特征。
To understand the history of paleoclimate changes in the Gulf of Thailand,we performed systematic geochemical and mineralogical study on the core T155 collected from the Gulf of Thailand.The rare earth element index of(La/Sm)_(UCC)-(Gd/Yb)_(UCC) diagram for sediments indicate that the sediment source in the southwestern Gulf of Thailand was relatively stable since the Holocene and mainly from the Malay Peninsula,and the coastal current controlled by the seasonal monsoon was the main driving force.Based on the proxies of kaolinite/(chlorite+illite),chemical alteration index(CIA)and potassium aluminum ratio(K/Al)in the core T155,this study divided the Holocene paleoclimate evolution into the following two stages,①The early-middle Holocene(12000 cal a BP-6500 cal a BP):the values of kaolinite/(chlorite+illite)and CIA were high,indicating the strong East Asian summer monsoon in this period.During this stage,kaolinite/(chlorite+illite)value and CIA appeared two low value periods,corresponding to two high value of K/Al,which occurred in 11200 cal a BP-10500 cal a BP and 8500 cal a BP-7500 cal a BP,respectively,indicating the response of the Gulf of Thailand to two global millennium scale climate events(the younger dryas event and the 8.2 ka cold event).②After the middle Holocene(6500 cal a BP):the values of kaolinite/(chlorite+illite)and CIA have decreased significantly,indicating that the East Asian summer monsoon has gradually weakened during this period.At the period that from 3200 cal a BP to 1800 cal a BP,the geochemical and clay mineral indexes showed an obvious low value,which corresponds to the“Pulleniatina Minimum Events”in the tropical sea area,implying the good regional response to global climate change in the Gulf of Thailand.
作者
袁帅
张辉
曹鹏
李小艳
石学法
范德江
Somkiat Khokiattiwong
Narumol Kornkanitnan
刘升发
YUAN Shuai;ZHANG Hui;CAO Peng;LI Xiao-yan;SHI Xue-fa;FAN De-jiang;SOMKIAT Khokiattiwong;NARUMOL Kornkanitnan;LIU Sheng-fa(College of Marine Geosciences,Ocean University of China,Qingdao 266100,China;First Institute of Oceanography,MNR,Qingdao 266061,China;Key Laboratory of Marine Geology and Metallogeny,MNR,Qingdao 266061,China;Laboratory for Marine Geology,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266061,China;Marine and Coastal Resources Research and Development Institute,Department of Marine and Coastal Resources,Bangkok 10210,Thailand)
出处
《海洋科学进展》
CAS
CSCD
北大核心
2022年第2期233-246,共14页
Advances in Marine Science
基金
全球变化与海气相互作用专项——南海SCS-CJ03区块底质调查与研究(GASI-02-SCS-CJ03)和亚洲大陆边缘“源-汇”过程与陆海相互作用(GASI-GEOGE-03)。
关键词
古气候
全新世
稀土元素
黏土矿物
泰国湾
paleoclimate
Holocene
rare earth element
clay mineral
Gulf of Thailand
