湖泊记录中的古气候和古环境指标及其地质灾害信息

The preliminary study of palaeoclimatic and palaeoenvironmental indicators and their information on geological disasters in lake records

关键词:  古气候  古环境  多种代用指标  地质灾害信息  湖泊记录

Key words:  palaeoclimate  palaeoenvironment  multi-indicator  information on geological disasters  lake record

摘要:

笔者在简略论述反映古气候、古环境的多种代用指标的基础上,讨论其在揭示地质灾害信息方面的意义,并分析从中提取地质灾害信息的方法和思路。认为在沉积物粒度判别基础上,沉积物表现出的较低δ¹⁸O值,较低δ¹³C值和较低碳酸盐含量以及较高的有机质含量特征可能指示了地质灾害方面的信息。

Abstract:

The occurrence of geological disasters is interpreted to be closely related to palaeoclimatic and palaeoenvironmental changes. In this paper, the authors present a new analysis of palaeoclimatic and palaeoenvironmental indicators and their information on geological disasters as revealed by lake records. For a given geological environment, when the precipitates reach their upper limits, some geological disasters such as landslides, collapses and clastic flows may be triggered. In other words they are often initiated in the areas where the amount and strength of the precipitates are great enough to cause the cyclic systems of ground water to be saturated. The information on geological disasters may be detected from grain sizes, lower δ¹⁸O and lower δ¹³C values, lower carbonate contents, and higher organic matter contents of the sediments preserved in the lacustrine environments.