GEOARCHAEOLOGY OF THE NORTHERN DEBED RIVER VALLEY, ARMENIA: PRELIMINARY RESULTS
Cultural materials at both sites lie within alluvial terraces of the Debed River. Work at the Middle Pleistocene site, Bagratashen-1, included mapping of the portion of the terrace in which the site resides, and detailed description and sampling of soil profiles in archaeological excavation trenches. The area mapped with differential GPS is approximately 87,000 m2 and included the site, the terrace, modern drainages that cut the terrace, and surrounding roads. Profile descriptions include color, texture, structure, and horizonation; profile sampling included bulk soil for laboratory analysis and soil blocks for petrologic analysis. Sampling for micromorphology targeted areas of high artifact concentration, soil transitions, diagnostic horizons, and paleosols. As the Late Pleistocene site, Ptghavan-4, is not currently under excavation, work there was limited to a single detailed profile description and will continue next summer. Soils at both sites contain gypsic horizons, with one paleosol at Bagratashen-1 containing a petrogypsic horizon.
In combination with the DGPS data for Bagratashen-1, soil laboratory analyses will address the bulk mineralogy and chemistry of the deposits, the flow of water through the landscape feature, and the physical and chemical interaction of soil precipitates and artifacts. Specifically we aim to address the relative timing of archaeological site-use, sediment deposition, and soil formation, as well as the potential for faunal preservation. Each of the two excavation trenches provided combined soil profiles of approximately 4 m depth. When combined with planned OSL dating and stable isotope ratio measurement, these profiles will serve as detailed paleoclimate chronologies specific to Middle Paleolithic site contexts and spanning these Pleistocene and Holocene deposits.