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• 1. [Article] Paleoenvironmental reconstruction of an active margin coast from the Pleistocene to the present : examples from southwestern Oregon

  This study illustrates geoarchaeological and paleoenvironmental approaches to the investigation of an active margin coastal setting and provides examples of how information gleaned through examination ...

  Citation × Citation Citation Abstract Copy Title: Paleoenvironmental reconstruction of an active margin coast from the Pleistocene to the present : examples from southwestern Oregon Author: Punke, Michele Leigh This study illustrates geoarchaeological and paleoenvironmental approaches to the investigation of an active margin coastal setting and provides examples of how information gleaned through examination of the stratigraphic record can reveal depositional signatures that provide insights into the geomorphic and tectonic forces active within coastal river basins. Three case studies from the southern Oregon coast illustrate the complex relationship between tectonics and geomorphic processes along an active margin coast such as Oregon's Cascadia subduction zone. This work illustrates that the differential preservation of late Pleistocene-age terrestrial deposits in Oregon's coastal landscape, and the early cultural sites they may contain, is not random but can be closely related to larger tectonogeomorphic processes operating at local and regional scales. Detailed subsurface investigation of one case study site, the lower Sixes River valley, reveals a complex history of depositional environment evolution in relation to geomorphic and tectonic forces. Litho- and biostratigraphic data sets are used to develop a depositional environment reconstruction for the lower Sixes River site through time. This reconstruction of the depositional environment from the late Pleistocene to the present indicates a transgressive evolution that differs from models of transgressive coastal facies and from other studied Northwest coast estuarine life histories. Factors such as eustatic sea level rise, regional and local tectonic alteration of the landscape, sediment supply, or valley morphology may have played roles in the creation and preservation of this atypical depositional sequence. Litho- and biostratigraphic evidence of six Cascadia subduction zone earthquakes younger than 6200 cal yr BP is recorded in a long sediment core from the Sixes River valley. All six of these events correlate with events previously reported for the area by Kelsey et al. (2002). At least five additional plate boundary earthquakes lowered tidal marshes and freshwater wetlands prior to 6200 cal yr BP. The presence within the lower Sixes River valley of an intertidal environment capable of recording Cascadia subduction zone earthquakes dating to the late Pleistocene and early Holocene has not been found at any other location on the Northwest coast. Title: Paleoenvironmental reconstruction of an active margin coast from the Pleistocene to the present : examples from southwestern Oregon Author: Punke, Michele Leigh This study illustrates geoarchaeological and paleoenvironmental approaches to the investigation of an active margin coastal setting and provides examples of how information gleaned through examination of the stratigraphic record can reveal depositional signatures that provide insights into the geomorphic and tectonic forces active within coastal river basins. Three case studies from the southern Oregon coast illustrate the complex relationship between tectonics and geomorphic processes along an active margin coast such as Oregon's Cascadia subduction zone. This work illustrates that the differential preservation of late Pleistocene-age terrestrial deposits in Oregon's coastal landscape, and the early cultural sites they may contain, is not random but can be closely related to larger tectonogeomorphic processes operating at local and regional scales. Detailed subsurface investigation of one case study site, the lower Sixes River valley, reveals a complex history of depositional environment evolution in relation to geomorphic and tectonic forces. Litho- and biostratigraphic data sets are used to develop a depositional environment reconstruction for the lower Sixes River site through time. This reconstruction of the depositional environment from the late Pleistocene to the present indicates a transgressive evolution that differs from models of transgressive coastal facies and from other studied Northwest coast estuarine life histories. Factors such as eustatic sea level rise, regional and local tectonic alteration of the landscape, sediment supply, or valley morphology may have played roles in the creation and preservation of this atypical depositional sequence. Litho- and biostratigraphic evidence of six Cascadia subduction zone earthquakes younger than 6200 cal yr BP is recorded in a long sediment core from the Sixes River valley. All six of these events correlate with events previously reported for the area by Kelsey et al. (2002). At least five additional plate boundary earthquakes lowered tidal marshes and freshwater wetlands prior to 6200 cal yr BP. The presence within the lower Sixes River valley of an intertidal environment capable of recording Cascadia subduction zone earthquakes dating to the late Pleistocene and early Holocene has not been found at any other location on the Northwest coast. Close

• 2. [Article] Geoarchaeological Investigations at the Devils Kitchen Site (35CS9), Southern Oregon Coast

  A geoarchaeological investigation was conducted at the Devils Kitchen archaeological site, located in the Devils Kitchen State Park along the southern Oregon coast. In this thesis research, the author ...

  Citation × Citation Citation Abstract Copy Title: Geoarchaeological Investigations at the Devils Kitchen Site (35CS9), Southern Oregon Coast Author: Curteman, Jessica Ann A geoarchaeological investigation was conducted at the Devils Kitchen archaeological site, located in the Devils Kitchen State Park along the southern Oregon coast. In this thesis research, the author paired previous and recent excavated stratigraphy profiles to define culturally significant deposits. These stratigraphic units were defined further geochemically using a multivariate statistical analysis from data gathered by a portable x-ray fluorescence. Radiocarbon dates from excavated charcoal samples associated with cultural artifacts show an intact deposit dating from 10,638±35 to 11,596±37 RCYBP. The author used textural analysis from Ro-Tap sieve shaker data and Munsell color identification extracted from 33 bucket auger units to subsurface test the Devils Kitchen State Park area. The auger samples portray an uplifted aeolian landscape once influenced by alluvial deposition, commonly observed along coastal environments altered by rising sea levels. This research applied a geoarchaeological method to identify deposits of the right age (DORA) that have the potential to contain intact, early evidence of prehistoric people. The identification of DORA can serve as a marker for future coastal research searching for rare, intact paleolandscapes and archaeological deposits dating to the late Pleistocene to mid Holocene. Title: Geoarchaeological Investigations at the Devils Kitchen Site (35CS9), Southern Oregon Coast Author: Curteman, Jessica Ann A geoarchaeological investigation was conducted at the Devils Kitchen archaeological site, located in the Devils Kitchen State Park along the southern Oregon coast. In this thesis research, the author paired previous and recent excavated stratigraphy profiles to define culturally significant deposits. These stratigraphic units were defined further geochemically using a multivariate statistical analysis from data gathered by a portable x-ray fluorescence. Radiocarbon dates from excavated charcoal samples associated with cultural artifacts show an intact deposit dating from 10,638±35 to 11,596±37 RCYBP. The author used textural analysis from Ro-Tap sieve shaker data and Munsell color identification extracted from 33 bucket auger units to subsurface test the Devils Kitchen State Park area. The auger samples portray an uplifted aeolian landscape once influenced by alluvial deposition, commonly observed along coastal environments altered by rising sea levels. This research applied a geoarchaeological method to identify deposits of the right age (DORA) that have the potential to contain intact, early evidence of prehistoric people. The identification of DORA can serve as a marker for future coastal research searching for rare, intact paleolandscapes and archaeological deposits dating to the late Pleistocene to mid Holocene. Close