Research progress in paleoclimatic interpretations of tufa and travertine

Abstract

Surface carbonate deposits have been divided into two broad groups, the tufa, which results primarily from the degassing of soil-borne aqueous CO₂, and the travertine resulting from the degassing of thermally generated CO₂. Because of differing sources and partial pressures of CO₂, the formative mechanisms and paleoclimatic interpretation of the two may be completely different. This article summarizes current situations and problems of research on the formative mechanisms and paleoclimatic interpretations of tufa and travertine. It emphasizes that further research should focus on determining the surficial, hydrodynamic and CO₂ conversion controls upon climatic proxies such as deposition rates, oxygen and carbon stable isotope ratios, and using them to make quantitative and/or qualitative analyses of the relationships between these proxies and climate (temperature, precipitation), human activity (land use and land cover change) or earthquake activity. This will provide new scientific support for understanding the response of the monsoon climate in China to global change and the true underlying mechanisms when making use of high-resolution records in tufa/travertine.