The Great Lakes Geologic Mapping Coalition (GLGMC), consisting of state geological surveys from all eight Great Lakes states, the Ontario Geological Survey, and the U.S. Geological Survey, was conceived out of a societal need for unbiased and scientifically defensible geologic information on the shallow subsurface, particularly the delineation, interpretation, and viability of groundwater resources. Only a small percentage (<10%) of the region had been mapped in the subsurface, and there was recognition that no single agency had the financial, intellectual, or physical resources to conduct such a massive geologic mapping effort at a detailed scale over a wide jurisdiction. The GLGMC provides a strategy for generating financial and stakeholder support for three-dimensional (3-D) geologic mapping, pooling of physical and personnel resources, and sharing of mapping and technological expertise to characterize the thick cover of glacial sediments. Since its inception in 1997, the GLGMC partners have conducted detailed surficial and 3-D geologic mapping within all jurisdictions, and concurrent significant scientific advancements have been made to increase understanding of the history and framework of geologic processes. More importantly, scientific information has been provided to public policymakers in understandable formats, emphasis has been placed on training early-career scientists in new mapping techniques and emerging technologies, and a successful model has been developed of state/provincial and federal collaboration focused on geologic mapping, as evidenced by this program’s unprecedented and long-term successful experiment of 10 geological surveys working together to address common issues.

This study investigates environmental change as a context for the location of occupation in campsites along the lower Nottawasaga River in southern Ontario, Canada. Evidence of Archaic and Woodland period campsites presents a difficult scenario for archaeological interpretation. Did Archaic cultures prefer to occupy higher ground, such as on the Edenvale moraine (206 m above sea level [a.s.l.]), or lower areas within river valleys, such as on the floodplain (181 m a.s.l.)? The aim of this study is to disentangle the evidence from a geoarchaeological perspective, considering cultural sites cross-temporally in their physical setting of a river floodplain in the Great Lakes region. We used geoarchaeological methods and methodologies, including soil-sediment analysis, sedimentological profiling of cutbanks and cores, topographic profiling in the field, river morphometric and hydrometric measurements using various techniques, ground-penetrating radar (GPR), and conceptual modeling. Results indicate that the Edenvale moraine, which topographically confines the channel and floodplain in the study area, may have led to catastrophic stripping of the floodplain during drainage of glacial lakes, causing the Nottawasaga River to downcut into the Edenvale moraine. This occurred following a period of floodplain stability, when natural and cultural deposits would have been preserved and buried in confined sections of the floodplain that are currently being vertically accreted. Any model that considers accretion style, such as the preservation-exposure model presented here, should be interpreted within the context of the environmental history of the area, since accretion style varies temporally and spatially at the river-reach scale.

ABSTRACT The deglaciation history of northeastern Minnesota and northwestern Ontario is outlined using geological and ichthyofaunal evidence from the continental to local scales. Both published and new data indicate the existence of eastern outlets drawing from pre-and-early Agassiz lakes. Part of the Arctic watershed was impounded between the Duluth Complex highlands and the retreating Rainy lobe. These outlets had their flows routed through the “Keating Complex” and the “Gunflint Arrow Lakes Corridor.” Discharges around the Duluth Complex’s northeast limb reached the Superior basin along Superior lobe ice, then exited down existing pre-glacial river valleys and a prominent, “valley-type” topographic bench between Hovland and Grand Marais, Minnesota.