Brett R . Lenz

A study is conducted on the numerical simulation of flow-induced sound of a wall-mounted finite length cylinder. A circular cylinder with a length-to-diameter ratio of 22.6 was considered at a Reynolds number of 11 700. The flow field is computed using a hybrid LES/RANS model and the far-field noise is calculated using the Ffowcs Williams and Hawkings acoustic analogy. The flow and acoustic results are compared with experimental results published by Moreau and Doolan in 2013.

This dissertation involves the development of a geologic framework applied to upper Pleistocene and earliest Holocene archaeological site discovery. It is argued that efforts to identify colonizer archaeological sites require knowledge of geologic processes, Quaternary stratigraphic detail and an understanding of basic soil science principles. An overview of Quaternary geologic deposits based on previous work in the region is
presented. This is augmented by original research which presents a new, proposed regional pedostratigraphic framework, a new source of lithic raw material, the Beezley chalcedony, and details of a new cache of lithic tools with Paleoindian affinities made from this previously undescribed stone source.

A Geographic Information Systems-based (GIS) model of archaeological site distribution to aid in the discovery of presently unknown archaeological sites within the state of Washington was developed. Located in the Pacific Northwest of the United States, the project area includes approximately 71,500 square miles, roughly the equivalent to 75% of the land area within the entire UK. To complete this study across such a large land area we applied 1:24000 scale pedologic and geologic data along with a limited range of other environmental variables and the known locations of recorded archaeological sites to create a predictive model of archaeological site locations. Once the environmental variables were determined, archaeological site location data from the recorded archaeological sites was used in combination with field-based archaeological survey locations and historic-period Indian encampment sites digitized from Government Land Office maps in order to develop the model. While limitations to the model include the inability to accommodate landform transformations and broad ecologic change through time, we consider the model to be very strong for the middle to late Holocene period and moderately strong for the upper Pleistocene through middle Holocene period.

Post Wisconsin alluvial stratigraphy of the mainstream Columbia River drainage developed by alternating cycles of alluvial deposition and landform stability. Holocene aggradation episodes followed closely behind the Upper-most Pleistocene catastrophic (Glacial Lake Columbia) floods dated in this study to 12,800+/-50 BP. Initiation of a multiple Holocene fine-grained terrace system commenced prior to 9000 BP and continued through to approximately 500BP. A comparison of stratigraphic sequences reveals that (1) extensive tracts of early Holocene floodplain are preserved along the mainstream Columbia River; (2) there is little variability in the age and character of the early Holocene terrace deposits; (3) sedimentologic and pedologic details of the early Holocene terrace are readily differentiated from later Holocene terraces; (4) early Holocene archaeological sites are commonly buried within the former floodplain. Details of the timing and stratigraphic characteristics of the earliest Holocene alluvial floodplain are presented.

Research into timing of final cross-Scabland floods related to recession of the Cordilleran ice sheet is reported. Numeric ages associated with final flooding span a 600 year period of Upper-most Pleistocene flood events. Numeric ages associated with final flooding include a date of 12,800+/-60BP on bone from a ruminant killed by one of the flood events, and a date of 12,130+/-50BP on the extinct Jefferson Ground Sloth (Megalonyx jeffersoni) which was discovered immediately overlying rhythmically bedded flood sediments. At least six successive flood occurrences post-date deposition of the St. Helens Set S tephra (~13,000BP). Sediments deposited as a result of these late floods include pedogenic and geologic evidence which indicate a depositional hiatus between individual flood events.

The shallow subsurface of the Scabland region of the Columbia Plateau in central Washington State, displays abrupt change in mode of deposition and sedimentation rates recorded in Pleistocene and early Holocene pedogenic sequences. Local depositional environment change occurred rapidly as a result of catastrophic flood sedimentation, the source of eolian and alluvial parent materials. Cross-Scabland flooding ceased between 12.8 and 12.1 KBP, while catastrophic floods that were restricted to the Columbia River valley post-date the fall of Glacier Peak tephra (11.2 KBP). Pedogenesis into these flood deposits and thin L1 loess at numerous Scabland locations is recorded in two soil-forming periods. The lower soil, termed the Bishop Paleosol, is characterized by a well-developed A horizon and relatively thin Cambic (Bw) or Argillic (Bt) horizons, depending on the depositional environment. The age of this soil is constrained by its relative position between Mt. St. Helens Set S (12.8±60KBP) and Glacier Peak tephras. Separating the two soils at several locations is a post-Glacier Peak tephra period of eolian deposition which may reflect disbursement of Columbia River Valley outburst flood sediments during the Younger Dryas cooling period. The second period of pedogenesis post-dates deposition of Glacier Peak tephra and pre-dates Mazama (7.7KBP) tephra deposition. This soil, termed the Badger Mountain paleosol, is characterized by multiple, stacked buried A (Ab) horizons, Cambic horizons and well developed Argillic horizons which may qualify as Natric soils. These strong B horizons overprint the deepest buried A horizons and the Bishop paleosol in some exposures. The cap of the Badger Mountain soil is characterized by a zone of extremely well-developed cicada burrowing up to 1m thick, indicating a shift to arid conditions after 11.2KBP.

While it is generally accepted that the initial Pleistocene human colonizers of the Americas likely entered the continents via the Pacific coast, formal models of their entry and dispersion into the continental interior are scarce. The ability to identify colonizer period archaeological sites for development of such models requires that researchers identify landforms of appropriate age and depositional character to target for large-scale archaeological survey. Well-preserved Upper Pleistocene and Early Holocene landforms are present across the Pacific Northwest. From coastal environs to the Palouse, these landforms represent a remnant landscape which initial colonizers explored at some point subsequent to the last glacial maximum. The types of landforms suitable for deposition and preservation of colonizer period archaeological sites include a broad array of settings, including: Coastal environments, characterized by relict Pleistocene-age landscape features shoreward of the submerged continental shelf; Continental ice-marginal and ice-distal depositional environments, where a variety of glaciomarine and long-standing glacial lakes formed behind the retreating Puget Lobe of western Washington State; Interior Scablands where cataclysmic outburst floods created scoured topographic lows that acted as local depositional basins—often holding paleo-lakes and marshes; and the Palouse loess within the Columbia Basin province, where eolian deposition has buried and preserved the Pleistocene and early Holocene landscape. Along the major drainageways, Upper Pleistocene to Early Holocene alluvial chronologies vary locally, but overall regional trends indicate that climate-controlled aggradation initiated between 12.0 to 11.0KBP, forming distinct terraces in the major river systems and their tributaries. Regional soil formation is evidenced by the Bishop Geosol which dates between 13.5KBP and 11.2KBP, present in a broad variety of depositional environments. Upper Pleistocene archaeology is sparse but present across the region; initial colonizers were broad-spectrum foragers whose toolkit included distinctive stemmed and shouldered bifaces, macroblade tools and crescents.

The “Clovis first” and “Ice Free Corridor” models of initial human colonization of the Americas fail to accommodate the earliest (Pre-11,000BP) Paleoindian archaeological sites. As a result the Coastal Entry Hypothesis has recently gained rapid support among Paleoindian specialists. While the details of coastal entry are sparse due to an inundated Pleistocene coastline and low visibility of the earliest sites, the unequivocal fact remains that at some point in time the first Americans left the coast and entered the continental interior. The most parsimonious explanation for interior colonization from the coast would have colonizers moving through natural travel corridors such as the Columbia River valley. Given its location relative to receding continental glaciers, models of initial human colonization along the Pacific coast should consider the Columbia River corridor as a viable and likely initial pathway to the continental interior. Geoarchaeological research at newly discovered sites supports this hypothesis and clearly demonstrates that Upper Pleistocene people exploited ecological zones of high productivity in Scabland tracts of the Columbia Plateau. Along the Columbia River corridor a generalized lack of Upper Pleistocene floodplain development by and large precluded deposition and preservation of Pleistocene archaeological sites; subsequent catastrophic flooding likely destroyed any such evidence. To the contrary, upland sites in Scabland tracts are well preserved and available to test hypotheses of initial colonization. Geomorphic and hydrogeologic features that are correlated with the earliest archaeological sites on the Columbia Plateau include (1) catastrophic fluvial deposits adjacent to scoured and denuded bedrock; (2) extinct paleolakes, marshes and remnant landforms associated with high stands of these bodies of water; and (3) alluvial terraces within scabland flood channels which formed as the result of post-flood dewatering and subsequent upper Pleistocene alluviation. By expanding research into the geologic and ecologic context of the Cordilleran interior it is possible to hypothesize how Pleistocene colonizers made the transition from marine to terrestrial adapted life ways. This analysis of Columbia Plateau geoarchaeology is an example of such research.

The later Palaeolithic sites on the East European plain are celebrated for their solid buildings constructed of mammoth bones. Were these permanent settlements, occupied
all the year round? Or were they seasonally occupied, in a land where winters are harsh? Stratigraphic explorations at Mezhirich, and excavation of the empty space between the buildings, leads to a decisive interpretation.

Sediment liquefaction features in Quaternary-age geological deposits are reported and described from the Lake Ilo Basin, North Dakota. Lake Ilo is located in Dunn County , North Dakota, about 6 k.m east of Killdeer, in the heart of the Williston Basin. The Lake Ilo Basin is an exceptional sedimentary environment for the formation and preservation of liquefaction structures. Alluvium in the valley lies on bedrock in many places and extends to depths in excess of fifty meters. Glacial till and outwash deposits bound glacio-fluvial and glacio-paludal sediments that were deposited during periods of glacio-fluvial alluviation along remnant and extinct Pleistocene drainage channels. Liquefaction is expressed as sand dikes, relict volcanoes, convolute bedding, and related water escape structures. Previous researcher on archaeological sites within the Lake Ilo Basin interpreted these liquefaction features as anthropogenic stone quarry pits. A large sediment dike discovered in the basin during the final season of fieldwork called for an altemative explanation for the origin of the reported quarry pits. Utilizing standard particle-size analysis procedures, chemical analyses of selected samples, and morphological comparisons to known liquefaction features at other locations on the U.S., I reinterpret many of the proposed quarry features. Based on sedimentary characteristics of the features and the improbability of other liquefaction triggers I propose a tectonic origin (seismic loading) hypothesis.