Doctoral Dissertation Research: Pedology and 10-Beryllium Dating of Colluvial Deposits in the Blue Ridge Mountains of North Carolina

早在19世纪80年代，像威廉·莫里斯·戴维斯这样的地貌学家就开发并测试了阿巴拉契亚山脉中部和南部的景观变化模型。然而，直到最近才有新的方法和理论被用来解释该地区复杂的混合地貌。测定材料年代的新方法为发展地貌和材料年表提供了相当大的希望。该博士论文研究项目将阐明南蓝岭的地貌和土壤历史，这些记录来自北卡罗来纳州西部小田纳西河流域的崩塌沉积物和相关土壤。除了在实地获得的其他数据外，还将提取从支流山谷中精心挑选的系列中提取的几组崩积层样品。崩塌样品的相对年龄将通过检查土壤形态特性、铁种类的比例和不同耐候性矿物的比例来确定。这些样品还将使用相对较新的测年技术进行检测，该技术测量铍（10-Be）的同位素。使用这种方法确定的日期应该能够确定每个样品的最大表面暴露年龄，从而能够在更定量的参考框架内检查这些沉积物和相关土壤的性质和演化历史。该项目将促进对阿巴拉契亚山脉南部蓝岭省的地貌和土壤变化的了解，为研究景观和土壤演变过程提供更坚实的时间背景。此外，它将探索10-Be约会程序的效用。作为博士论文改进奖，该奖项也将提供支持，使有前途的学生建立一个强大的独立研究生涯。

9405198 SCHAETZL As early as the 1880s, geomorphologists like William Morris Davis developed and tested models of landscape change in the central and southern Appalachian Mountains. Only recently have new approaches and theories been used to interpret the complex intermixture of landforms in the region, however. New methods for dating materials offer considerable promise for developing a chronology of landforms and materials. This doctoral dissertation research project will elucidate the geomorphic and soils history of the southern Blue Ridge as recorded in colluvial deposits and associated soils from the Little Tennessee River basin of western North Carolina. Sets of colluvium samples drawn from carefully selected series in tributary valleys will be extracted in addition to other data derived in the field. The relative ages of the colluvial samples will be determined by examining soil morphological properties, ratios of iron species, and rations of differentially weatherable minerals. The samples also will be examined using relatively new dating techniques that measure an isotope of beryllium (10-Be). Dates determined using this method should allow identification of a maximum surface exposure age for each sample, thereby enabling examination of the properties and evolutionary histories of these deposits and relative soils in a more quantitative frame of reference. This project will advance knowledge about geomorphological and pedological change in the Blue Ridge province in the southern Appalachians, providing a much firmer chronological context within which to examine processes of landscape and soil evolution. In addition, it will explore the utility of 10-Be dating procedures. As a doctoral dissertation improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.