The Pedo-Weathering Profile: A Paradigm for Whole-Regolith Pedology from the Glaciated Midcontinental United States of America
- John P. Tandarich,
- Robert G. Darmody and
- Leon R. Follmer
Pedologists and Quaternary geologists developed different viewpoints almost 70 yr ago regarding concept, designation, and application of zones of weathering, termed horizons by pedologists. A sense of exclusion separated pedologic and geologic domains. The pedologic domain was confined to the upper portion of the earth's surface exhibiting the master horizons of O or A (accumulation), E (eluvial), and B (illuvial) horizons—the solum. In contrast, the domain of Quaternary geology and its interest in soil stratigraphy was focused on a paradigm stressing the subsolum— the realm of the pedologic C horizon and below. We seek to develop a unified paradigm through the introduction of a unified pedoweathering profile (PWP) concept that requires a re-examination of the C horizon concept and the redefinition and use of master horizon D. The PWP contains a C horizon concept of more limited but more precisely defined scope than traditionally used in pedology. In the traditional sense, the interval between the solum and bedrock is designated as C whether modified or not. In the PWP, the C horizon is limited to the modified part of the traditional C that shows pedogenic connection to the overlying solum. The part that is unaltered by pedogenic processes and does not have the hardness of bedrock (R) is recognized as the D horizon. The redefined subsolum horizons are not limited to the glaciated area of the midcontinental USA where these concepts were originally formulated. They exist worldwide in glaciated areas, wetlands, and alluvial, lake, and coastal plains of the past and present. With the growing importance of soil properties at depth, the PWP concept should be useful in paleopedology, soil stratigraphy, geomorphology, sedimentology, hydrogeology, and Quaternary geology.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 1994. . Copyright © 1994 by the Soil Science Society of America, Inc., 5585 Guilford Rd., Madison, WI 53711 USA