Soil-Stratigraphic Correlation of a Doline in the Valley and Ridge Province
1994
Crownover, S. H. | Collins, M. E. (Mary Elizabeth) | Lietzke, D. A.
Dolines of the Valley and Ridge Province of eastern Tennessee act as sediment traps and can provide detailed information on the recent geomorphic history of the surrounding landscape. The objective of this study was to determine the soil stratigraphy, age, morphology, and late Quaternary history in an upland doline on the Mascot Formation in eastern Tennessee. Soils were sampled on the doline rim (DR), upper sideslope (US), lower sideslope (LS), and near the doline center (DC). Pedogenesis of this large upland doline is related to parent material and geomorphic processes. Stratigraphy, age, and morphology varies among the soils. Pedon DC has two buried soil profiles. The upper buried A horizon (2Ab) was radiocarbon dated to 320 ± 70 years before present (YBP). This horizon separates a weakly developed, yellowish brown soil above, with 10 to 20% chert that formed in post-European agricultural-related sediments (late 18th and 19th centuries) with laminae, from silty pre-European sediments (middle to late Holocene) that are low in chert but contain an argillic horizon. The second buried horizon (3Ab) was dated at 6100 ± 100 YBP and provides evidence of landscape stability during the middle Holocene, probably during the Hypsithermal Interval. Below this horizon, the soil has less clay and chert content varies. In contrast, Pedon DR has only a veneer of cherty silt loam late Holocene colluvium and cherty clay Mascot residuum. Geomorphic processes of mass wasting and slope wash on the doline sideslopes have provided a variety of sediments that have been trapped within this doline and subsequently subjected to pedogenesis.
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