USING GEOARCHAEOLOGY, GEOMORPHOLOGY, SURFICIAL GEOLOGY AND PEDOLOGY TO DETERMINE THE LATE QUATERNARY HISTORY OF THE KANAWHA RIVER VALLEY, WEST VIRGINIA

Most of the alluvial landforms in the Kanawha River Valley were formed during the late Quaternary by a combination of geomorphic processes. Major processes acting in the valley included base level rise due to glacial outwash aggradation on the Ohio River, incision of valley fill deposits after the retreat of glaciers from the Ohio River basin, increased periglacial sediment supply to the upper reaches of Kanawha River from the Appalachian Mountains, and complex response mechanisms.

Research techniques and data derived from geoarchaeology, geomorphology, surficial geology and pedology were used to identify alluvial landforms in the Kanawha River Valley, determine their method of formation, and to establish a chronology of their formation. The data indicate that an influx of glacial outwash caused aggradation in the Ohio River Valley about 22 ka B.P., which raised the base-level of the Kanawha River and resulted in a back-filling of the valley. Glaciers retreated from the Ohio River basin by 13 ka B.P., reducing sediment supply and triggering incision on the Ohio and Kanawha Rivers that created a well-defined late Wisconsin terrace at about 600 feet in elevation in the Kanawha River Valley.

An early Holocene terrace at about 580 feet in elevation was also identified in the Kanawha River Valley which formed because of a complex response initiated by late Wisconsin incision and early Holocene knickpoint migration. Well-dated stratigraphic sequences at St. Albans and Dunbar show unconformities between Late Wisconsin and Holocene deposits. Levee development was also an important component in the formation of the early Holocene terrace and sedimentation rates of >4 m/ka have been documented on the levees.

The presence of early Archaic (8 ka to 9 ka B.P.) sites on levees of the lower Kanawha River indicates that the river has been relatively stable during the last 8,000 years and has not meandered significantly over that time.