| 摘要: |
| 定量重建古高度是当前地球科学的重要进展之一。本文概述了降水稳定同位素组成定量重建古高度的两种不同途径，也就是经验回归方程和理论公式计算同位素直减率的两种方法；讨论了降水氧同位素组成重建古高度的主要误差来源和相对大小。根据亚洲季风区石笋记录，本文进一步分析了气候和环境变化对降水氧同位素组成及降水同位素直减率的影响，指出使用现代降水氧同位素值及同位素直减率重建青藏高原古高度所引入的偏差可能是其他所有误差来源的总和；不同海拔高度的洞穴石笋研究有望提供不同气候和环境条件下的降水同位素直减率；认识和理解沉积地层发育时的气候和环境条件，选择合适的同位素直减率曲线和低海拔地区降水同位素组成，综合运用多种重建方法进行交叉检验将显著减小定量重建古高度的偏差。 |
| 关键词: 降水氧同位素 同位素直减率 古高度 气候变化 洞穴石笋 |
| DOI： |
| CSTR： |
| 分类号:P531 |
| 文献标识码:A |
| 基金项目: |
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| The uncertainty associated with the climate change in the stable isotope based paleoaltimetry: the new insights from the study of stalagmites |
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CAI Yan-jun, QIN Shi-jiang1,2,3
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1.State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences,
Xi′an 710075, China;2.Institute of Global Environmental Change, Xi′an Jiaotong University, Xi′an 710054, China;3.Graduate University of Chinese Academy of Sciences, Beijing 100049, China
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| Abstract: |
| One of the most important developments in Earth Science is the invention of quantitative reconstruction of paleoelevation. This paper summarizes two approaches adopted in the stable isotope based paleoaltimetry, i.e., empirical calibrations of the isotopic lapse rates of precipitation and theoretical calculations of the isotopic lapse rates of precipitation, and address the origins and ranges of the deviation associated with these methods. Based on the study of the stalagmites in Asian monsoon regions, the paper further evaluates the errors induced by the climate change in the reconstructions of both the precipitation isotope composition and the stable isotope lapse rate, and points out that the deviation associated with the climate change may equal to the sum of other error sources; the study of the stalagmite from caves located at different elevations may help to establish the isotope lapse rate under different climatic and environmental conditions; understanding the climatic and environmental background when the strata formed, selecting the appropriate isotope lapse rate and isotope composition of precipitation at low elevation site, and using multiple approaches for cross check will remarkably minimize the deviation of the reconstructed paleoelevation. |
| Key words: oxygen isotope of precipitation isotope lapse rate paleoelevation climate change stalagmite |
