Spatial Signatures of Soils and Sediments: Geomorphic Research on Silty Soils in the Midwest USA

土壤地貌学研究通常将土壤和地貌学的野外和实验室工作联系起来，以回答景观演变的问题。在这个框架内工作，这个项目将为美国中西部部分地区制作空间数据集，即在粉质表层沉积物中形成的土壤的矿物学和质地特征的详细地图。换句话说，我将确定三个中西部次区域的粉质土壤的空间特征，并将这些特征与已知的黄土土壤区域进行比较，以确定这三个地区的土壤是否都是在粉质黄土或其他粉质沉积物中形成的。利用这些空间特征图，我也应该能够确定这些地区的泥沙来源区域。这些地图是为中西部北部三个“异常”粉质土壤地区绘制的，构成了这项研究的核心。这些地区是(1)格雷林指（Grayling Fingers）和(2)密歇根州北部下游的巴克利平原（Buckley Flats）地区，以及(3)密歇根州上半岛（UP）和威斯康星州东北部-西部UP边境地区的佩舍基高地。在现场，使用现有的数字土壤地图和GPS，我将在这三个区域内定位和取样具有异常粉砂质纹理的土壤。然后，这些土壤的样本将被带回地理系的第四纪景观研究小组实验室进行进一步分析。来自土壤及其母质的数据，如矿物数量、颜色、质地、颗粒形状、岩性、母质厚度等，将被分析以确定每种土壤的母质特征，定量地将其与特定的母质联系起来，即给予其沉积学特征。特定土壤的沉积学特征图就是我上面提到的空间特征图。确定这些土壤上的淤泥是否为黄土，这可能至少存在于三个地区中的一个，将通过比较三个地区中每个地区土壤的空间特征和土壤的空间特征和特征来确定，这些特征和特征将已经从威斯康星州西部和伊利诺伊州西北部的厚黄土地区取样。使用该协议生成的数据应该在空间上有系统地和可预测地变化，并且可能为研究景观演变打开新的大门，以前这些研究可能会充满不可逾越的“数据需求”障碍。从这项研究中可以获得的协同效应和知识收益将刺激对景观演变的新研究，并为科学界和非专业人士提供机会，以以前不可能的方式检查土壤和沉积物模式。这项研究将增加我们对自最后一次冰期结束以来在中西部上游运行的风力驱动和土壤系统的理解。这种以实地和实验室为导向的研究也将磨练和扩展一种方法，这种方法可能成为许多土壤地貌学研究的标准，为详细的资源测绘提供一种经过测试的方法。这种方法也可以帮助土壤制图者重新绘制该地区的土壤，并将提高对土壤图在地理研究中的效用的认识。最后，本项目的研究将为几名研究生和本科生提供教育机会，并建设密歇根州立大学的科学基础设施。

AbstractBCS-0422108Randall SchaetzlMichigan State UniversitySoil geomorphic research usually links field and lab work in soils and geomorphology to answer questions about landscape evolution. Working within that framework, this project will produce spatial data sets, i.e., detailed maps of mineralogical and textural characteristics, of soils developed in silty surficial sediments, for parts of the midwestern USA. Put another way, I will ascertain the spatial signatures of silty soils in three midwestern subregions and compare these signatures to areas of known loessial soils, to determine if the soils in each of these three regions have formed in silty loess - or some other silty sediment. Using these spatial signatures maps I should also be able to ascertain the source areas of the silts in these regions. The maps, created for three areas of "anomalous" silty soils in the upper midwest, form the core of the research. These areas, set within otherwise sandy landscapes, are (1) the Grayling Fingers and (2) the Buckley Flats regions of northern lower Michigan, and (3) the Peshekee Highlands in Michigan's Upper Peninsula (UP) and in the NE Wisconsin - western UP border area. In the field, using existing digital soil maps and a GPS, I will locate and sample soils that have anomalously silty textures within these three regions. Samples from these soils will then be taken back to the Quaternary Landscapes Research Group lab in the Department of Geography, for further analysis. Data from the soils and their parent materials, e.g., mineral amounts, colors, textures, particle shapes, lithologies, parent material thickness, etc., will then be then analyzed to determine parent material characteristics for each soil, quantitatively tying it to a specific parent material, i.e., giving it a sedimentologic signature. Maps of specific soils' sedimentological signatures are the spatial signatures maps that I refer to above. Ascertaining whether the silt cap on these soils is loess, which it is likely to be in at least one of the three regions, will be determined by comparing the spatial signatures of soils within each of the three regions to spatial signatures and characteristics of soils that will have already been sampled from the thick loess regions of western Wisconsin and NW Illinois. The data generated using this protocol should vary systematically and predictably across space, and may open new doors for research into landscape evolution that previously would have been fraught with insurmountable "data needs" obstacles. The synergies and knowledge gains that can be achieved from this research will stimulate new research on landscape evolution and provide opportunities for the scientific and lay communities to examine soils and sediment patterns in ways that have previously been impossible. The research will add to our understanding of wind-driven and soils systems that have operated in the upper midwest since the end of the last glaciation. This field- and lab-oriented research will also hone and expand a method that may become a standard for many soil geomorphology studies, providing a tested method for detailed resource mapping. This method may also assist soil mappers as they remap the region's soils and will heighten awareness of the utility of soil maps in geographic research. Finally, the research undertaken in this project will provide educational opportunities for several graduate and undergraduate students, as well as building the scientific infrastructure of MSU.