A proposal of new isotope geothermometer from lake sediments

新型湖泊沉积物同位素地温计的提案

• 批准号: 23651013
• 负责人: KITAGAWA Hiroyuki
• 金额: $ 2.58万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Challenging Exploratory Research
• 财政年份: 2011
• 资助国家: 日本
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23651013/
• 关键词: 気候変動; 安定同位体; アジア; 湖沼堆積物; 酸素同位体; セルロース; 珪藻; 気候プロキシ

The past climate change is recorded on lake sediments. However, the records obtained from the lake sediments are subject to the influence of two or more environmental factors. The data interpretation is not easy task. In this research, a new approach was proposed and examined for quantitative reconstruction of lake water temperature. The isotope thermometer are based on the premise that aquatic celluloseδ^<18> O serves as a direct proxy for lake waterδ^<18> O, thereby allowing resolution of temperature signals inδ^<18> O records from co-existing diatom silica frustules which are influenced by lake water temperature and lake waterδ^<18> O The diatom. cellulose isotope-thermometer was applied to the sediments from Lake Biwa(central Japan) and a marr lake in Inner Mongolia on a trial basis. Although our current data set cannot support more accurate scaling of developed isotope-thermometers, the difference in the presumed temperature was in agreement with the growth season temperature difference of two areas. It was confirmed that this novel multi-isotope approach clearly has much to offer the information of climate changes in continental environments.

过去的气候变化被记录在湖泊沉积物上。然而，从湖泊沉积物中获得的记录受到两个或两个以上环境因素的影响。数据解释并不是一件容易的事情。在这项研究中，提出并检验了一种新的湖水温度定量重建方法。同位素温度计是基于这样的前提，即水生纤维素δ；18&gt；O作为湖水δ；18&gt；O的直接替代物，从而可以从共存的硅藻硅体中分辨出δ^&lt；18&gt；O记录中的温度信号，这些记录受到湖泊水温和湖水δ；18；O硅藻的影响。对日本中部的琵琶湖和内蒙古的玛尔湖沉积物进行了纤维素同位素测温仪的试验。虽然我们目前的数据集不能支持对已开发的同位素温度计进行更准确的定标，但推定温度的差异与两个地区的生长季温差是一致的。已经证实，这种新的多同位素方法显然可以提供大陆环境中气候变化的信息。