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Holocene Lake-Level Change and Submerged Archaeological Site Potential of Rice Lake, OntarioSonnenburg, Elizabeth 12 1900 (has links)
<p> Isostatic rebound and climatic changes throughout the Holocene have
resulted in several periods of lowered water-levels in the Great Lakes watershed.
The Early Holocene lowstand phase corresponds with the Paleoindian period in
the Great Lakes Region (11,000-9000 YBP), and subsequent water-level rise has
inundated Paleoindian archaeological sites. This research sought to reconstruct
the water-level history of Rice Lake (located north of Lake Ontario) in order to
identify areas of high potential for submerged prehistoric sites. </p> <p> Over 750 line km of detailed geophysical data (single-beam bathymetry)
and 16 sediment cores were collected over a 30 km2 area of Rice Lake. Sediment
cores were visually logged and analyzed for particle size, microfossils and
microdebitage. Water-level reconstructions accounting for sediment infill and
isostatic rebound of the lake record a post Lake Iroquois (after 12 ka BP) Early
Holocene lowstand (~10-12 m below present level (bpl)) (EH-1). At 10 ka BP,
gradually rising water-levels and establishment of wetlands as indicated by
thecamoebian assemblages coincide with a newly discovered Paleoindian
occupation of the Mcintyre basin, where quartz microdebitage was found. Waterlevel
continued to rise to almost 2 m bpi until 6.5 ka BP, when warmer and drier
temperatures caused a sudden drop in water-levels as recorded by a pollen hiatus.
After 4 ka BP, water-levels quickly recovered and stabilized as shown by rapid
recovery of pre-hiatus thecamoebian biofacies and the establishment of wild rice
stands. </p> <p> The small number of known, well-preserved Great Lakes Paleoindian sites
has limited analysis of Early Holocene population densities, migration patterns,
cultural diffusion, or the chronology of settlement. The method of modelling
water-level fluctuations and associated archaeological potential developed in this
thesis represents a substantial advance in our understanding of Early Holocene
archaeology in the Great Lakes. These methods will have broader application to
exploration of submerged terrestrial landscapes elsewhere in the Great Lakes and
will allow for future regional synthesis of archaeological site distribution and
characteristics. </p> / Thesis / Doctor of Philosophy (PhD)
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