The Submerged Cypress Forest and the Paleolandscape of the Gulf of Mexico

Summary

Submerged Paleo-geologic features with probability for associated prehistoric sites on the Gulf of Mexico shelf include coastal plain and fluvial valley-fill deposits (e.g. terrace and floodplains) preserved landward of the 60-m bathymetric contour, the approximate late Pleistocene (~12,000 ka) shoreline location. A site ~15 km offshore Alabama was discovered with exposed remains of a previously-buried bald cypress forest with stumps in growth position rooted in an organic-rich paleosol. It has been suggested that exposure resulted from seafloor scour during Hurricane Ivan in 2004. Results from radiocarbon dating and OSL analysis place the timing of tree growth and burial at ~40-60 ka. We hypothesize that rapid floodplain aggradation associated with upstream response to sea-level rise led to burial and preservation. Though much older than expected Paleoindian occupation in this region, this rare find provides an opportunity to study in situ formation and preservation processes of an extent and easily accessible sub-sea preserved Pleistocene landscape surface and paleosol. These results will be used to create a conceptual model to aid in developing geophysical/geological survey techniques to identify buried paleolandforms that could contain archaeological remains from the earliest human occupations along the Gulf of Mexico coast when sea level was lower than today.

This Resource is Part of the Following Collections

• Society for American Archaeology 83rd Annual Meeting, Washington, DC (2018)

Keywords

Spatial Coverage

Record Identifiers

Abstract Id(s): 20357