AN APPLICATION OF PROBABALISTIC SUBSURFACE SAMPLING IN COLONIZER SITE DISCOVERY, PACIFIC NORTHWEST REGION, USA

Across the Pacific Northwest region there is mar­ked differential visibility of archaeological material from various upper-Pleistocene and earliest Holocene strata. In alluvial settings the surface horizons contain late prehistoric archaeology and colonizer horizons lie deeply buried. In the continental interior, in megaflood settings, depth to upper-Pleistocene flood sediment is often less than 50 centimeters. The full complement of culture history is compressed within this narrow range and the probability for identification of colonizer age archaeology by surface survey alone is relatively high. But these shallow environments are relatively rare across the state. To complete this analysis, present survey strategies were submitted to probabalistic analyses, based on a statistically significant sample. If current subsurface archaeological survey methodologies are followed in attempts to discover colonizer sites (Based on the current State of Washington Department of Archaeology and Historic Preservation survey standards and practice), chances of their discovery remain exceedingly low. The calculated subsurface shovel probe grid density required to identify most colonizer sites stands in stark contrast to the standard approach at archaeological reconnaissance survey. This is based on survey work represented by the past 1,950 surveys in the state of Washington (as of 2010), which applied very coarse subsurface intervals, when they were used at all. Under the present identification scenario, archaeological site reconnaissance surveys miss the majority of colonizer (Pleistocene) archaeological sites. In the Pacific Northwest, it is clear from an analysis of our probabilistic data that even if we are able to understand where colonizer sites might occur, as a discipline we are not applying adequate methodologies to find them.