THE GEOMORPHOLOGY OF THE PIG POINT SITE (18AN50): LANDFORM DEVELOPMENT, CLIMATE CHANGE, AND LONG-TERM HUMAN OCCUPATION

Pig Point (18AN50), lying well above the 500 year floodplain of Maryland’s Patuxent River, exhibits intact stratigraphy that spans nearly 10,000 years and has archaeological deposits occurring more than 6 feet (2m) below the surface. Archaeologists have long puzzled over how this promontory bluff developed and what geomorphological processes were involved to create such a unique landform. Based on diagnostic composition of source-bordering aeolian sand soils, the superposition of pedo-stratigraphic horizons, the stratigraphic chronology from multiple archeological C-14 dates and diagnostic artifacts, and stratigraphic 3D Modeling and analysis; we posit the site was formed through a combination of geomorphic processes which evolved through thousands of years of climate-driven erosional and depositional cycles including (a) Late Pleistocene deposition of active source-bordering aeolian dunes from braid-plain river sediments; (b) terrace scarp erosion during the warm wet interstadial culminating in the cool and dry Younger Dryas; (c) Holocene landform stabilization during the Pre-Boreal/Boreal Early Archaic; (d) colluvial over-printing (increased mass wasting) of aeolian sands during the Atlantic warm and dry Hypsithermal and Middle and Late Archaic periods; (e) development of an anthropogenic “midden” during the more stable Sub-Atlantic/Scandic/Neo-Atlantic and Early and Middle Woodland Periods; and (f) additional colluvial over-printing and mass wasting during the Pacific/Little-Ice Age, Late Woodland, and Historic Periods Native Americans began to inhabit the landform in the Early Archaic Period and artifacts and features were buried through time via colluvial slope wash of relic fluviomarine and aeolian sand sediments.