SEDIMENTARY STRATIGRAPHY, HOLOCENE LANDFORM EVOLUTION AND NATURAL SITE FORMATION PROCESSES AT THE WEST BLENNERHASSETT ARCHAEOLOGICAL SITE (46WD83-A), WOOD COUNTY, WEST VIRGINIA

The West Blennerhassett site (46WD83-A) is a deeply stratified archaeological site located on Blennerhassett Island in the Upper Ohio River Valley. Archaeological investigations exposed occupation deposits extending to a minimum of 5 m depth and dating from ca. 8660 radiocarbon years B.P. Results of particle-size analysis on alluvial sediments, bolstered by a robust radiocarbon chronology, reveal stages of landform evolution and provide a sedimentary context for occupation deposits.

West Blennerhassett was a rapidly accreting near-channel environment prior to ca. 7010 B.P. Early Archaic archaeological assemblages were isolated within a unit of relatively coarse-grained sediments and weakly developed soil horizons. An occupation hiatus from ca. 7010 B.P. until 4315 B.P. is indicated by a total absence of artifacts and features ; fine-grained sediments and slow sedimentation rates indicate a quiescent setting and low-energy overbank flooding at the site during this interval. Vertical accretion of the landform, as well as horizontal and lateral migration of the channel, caused the site to become increasingly distal from the Ohio River during the late Holocene and flooding of the site required larger magnitude floods. Slow sedimentation rates during the late Holocene resulted in minimal vertical separation between assemblages from serial occupations and occupation-specific archaeological assemblages that postdate ca. 4315 B.P. are essentially indiscernible. A sedimentary discontinuity at ca. 3000 B.P. registers in the granulometry as an increase in mean grain size and marks the shift to a higher-energy flood regime.