有孔虫壳体的Mg/Ca比值在古环境研究中的应用  

THE APPLICATION OF FORAMINIFERAL SHELL Mg/Ca RATIO IN PALEO-ENVIRONMENTAL STUDIES

作　　者：李建如[1] 

机构地区：[1]同济大学海洋地质国家重点实验室,上海200092

出　　处：《地球科学进展》2005年第8期815-822,共8页Advances in Earth Science

基　　金：国家重点基础研究发展规划项目"地球圈层相互作用中的深海过程和深海记录"(编号:G2000078500);科技基础性工作和社会公益研究专项"中国综合大洋钻探计划预研究"(编号:2003DIB3J114);国家高技术研究发展计划"大洋钻探技术预研究"(编号:2004AA615030)资助.

摘　　要：有孔虫壳体的Mg/Ca比值测定是目前估算海水古温度最受重视的方法,适用于低纬和高纬、表层和深层海水古温度的测定。该方法理论误差仅为±1.1℃,考虑到盐度以及海水pH值的影响,其误差为±1.3℃。运用此法推算出的热带海区表层海水温度领先于全球冰盖的变化,是热带过程调控冰期旋回最强有力的证据之一;与氧同位素相结合,还成功地运用于全球冰量的估算,是目前古环境研究中较常用的古温度测试手段。Measurement of Mg/Ca ratio of foraminifera shell is the most popular means in calculating seawater paleotemperature now. It is applicable in low and high latitude areas, to determine surface and deep seawater temperatures. The standard error is 1.1℃ , and when the effects of salinity and pH are considered, the error increases to ±1.3℃. The tropical sea surface temperature obtained from Mg/Ca ratio appears to lead ice sheet demise by -3ka, which suggests a prominent role of the tropics in pacing ice age cycles. Combining the oxygen-isotope paleo-temperature equation, the Mg/Ca ratio of foraminifera shell yields the δ^18O-water at the time of shell precipitation and the changes of the global ice sheets. This approach has become a good thermometer in determining paleotemperature variations in paleo-environmental studies.

关 键 词：有孔虫壳体 Mg/Ca比值 海水温度 古环境 

分 类 号：R736.4[医药卫生—肿瘤]