COLLABORATIVE RESEARCH: Morphology, Geochemistry and Stable Isotope Compositions of Vertic Paleosols as Indicators of Paleozoic Paleoclimates

这是C.I.Mora和S.G.Driese(田纳西大学；牵头机构)和D.E.Fastovsky(罗德岛大学)的合作研究，以支持正在进行的关于古生代古气候方面的研究，这些方面反映在阿巴拉契亚沉积序列中南部保存的垂直特征的古土壤中。这项研究利用了这些古土壤广泛的时空分布和气候依赖性，以及它们对稳定同位素分析的适应性。垂直古土壤的形态、地球化学和稳定同位素组成构成了这项研究的数据库。垂直特征的古土壤暴露在六个州，代表了从奥陶纪到二叠纪的河流和边缘海洋环境。由于与其他古土壤类型相比，垂直古土壤是对特定气候变量的诊断，如年干湿旋度和副热带至热带条件，因此这些古土壤是重建古气候变量的理想对象。此外，成壤碳酸盐的普遍存在使得能够估计年降雨量(根据结核层位深度)，以及有机会估计古生代大气二氧化碳分压和测试整个古生代大部分时间的全球大气二氧化碳浓度模型。

This is a collaborative research between C.I. Mora and S.G. Driese (University of Tennessee; lead institution) and D.E. Fastovsky (University of Rhode Island) to support ongoing research on aspects of Paleozoic paleoclimates that are reflected in vertic-featured paleosols preserved in the central and southern Appalachian sedimentary sequence. The study takes advantage of the wide spatial and temporal distribution and climatic-dependency of these paleosols, as well as their amenability to stable isotopic analysis. Morphology, geochemistry, and stable isotopic compositions of the vertic paleosols form the database of the study. Vertic-featured paleosols are exposed in six states, representing fluvial and marginal-marine environments from the Ordovician through the Permian. Because vertic paleosols are, by comparison with other paleosol type, diagnostic of specific climatic variables such as annual wet/dry cyclicity and subtropical to tropical conditions, these paleosols are ideal subjects for the reconstruction of paleoclimatic variables. Moreover, the common occurrence of pedogenic carbonate permits the estimation of annual rainfall (based upon nodular horizon depth), as well as the opportunity to estimate Paleozoic atmospheric pCO2 and to tests of models of global atmospheric CO2 concentrations throughout most of the Paleozoic Era.