A5081262531- Geology and Paleoclimatology Research
- Geological formations and processes
- Cryospheric studies and observations
- Landslides and related hazards
- Methane Hydrates and Related Phenomena
- Pleistocene-Era Hominins and Archaeology
- Geological Studies and Exploration
- Hydrocarbon exploration and reservoir analysis
- Aeolian processes and effects
- Geochemistry and Geologic Mapping
- Archaeology and ancient environmental studies
- Marine and environmental studies
- Isotope Analysis in Ecology
- Atmospheric and Environmental Gas Dynamics
- Climate change and permafrost
- Remote Sensing and LiDAR Applications
- Forensic Anthropology and Bioarchaeology Studies
- Groundwater and Isotope Geochemistry
- Hydrology and Sediment Transport Processes
- Coastal and Marine Dynamics
- Geological Modeling and Analysis
- Soil erosion and sediment transport
- Geological Formations and Processes Exploration
- Mechanics and Biomechanics Studies
- Amazonian Archaeology and Ethnohistory
University of Wisconsin–Superior
2013-2024
University of Minnesota, Duluth
2004-2020
Mercyhurst University
2007-2010
Paleoclimate proxy records reveal a pervasive cooling event with Northern Hemispheric extent approximately 9300 years ago. Coeval changes in the oceanic circulation of North Atlantic imply freshwater forcing. However, source, magnitude, and routing meltwater have remained unknown. Located central America, Lake Superior is key site for regulating outflow glacial to oceans. Here, we show evidence an 45-meter rapid lake-level fall this basin, centered on calibrated before present, due failure...
This study establishes a detailed lake-level history for the Lake Superior basin by mapping strandlines from 10-m and 3-m digital elevation models. There are 24 levels above mid-Holocene Nipissing level, elevations increase along direction of 23.1° due to post-glacial rebound. The highest Epi-Duluth, is steeper than subsequent may pre-date View ice advance into western at end Younger Dryas stade. most prominent level Duluth, ca. 10,800 cal yr BP. Ice retreat exposed successively lower...
Reconstruction of deglacial ice margins provides insights into the demise past sheets and ice‐marginal lakes helps to understand how former responded climate change. Here, we reconstruct Laurentide Ice Sheet across Manitoba (Canada), a dynamic region that in MIS 2 spanned from an inner core Keewatin dome periphery sheet (~900 km north Last Glacial Maximum limit). The area was also overrun by flowing both Quebec‐Labrador Hudson Bay Saddle. surficial landscape contains inherited relict...
The analysis of faecal stanols in lake sediment cores offers a novel opportunity to reconstruct human population change, assuming that variability stanol concentration is reliable proxy for relative populations. ancient lowland Maya Mesoamerica represents an important society whose demographic dynamics many locations remain uncertain. We apply the core retrieved from adjacent archaeological site Itzan, centre southwestern lowlands. sedimentary record Laguna Itzan implies substantial...
Abstract Glacial varves can detail ice-margin positions and provide a proxy for meltwater discharge at resolutions comparable to those of the Greenland ice core archives, thus they be critical paleorecords assessing response both ancient modern sheets climate change. Here we an ∼1500 yr varve chronology straddling Younger Dryas (YD)–Holocene boundary (11.65 cal. kyr B.P.), first such in North America. The are from glacial Lake Agassiz (central America). is pinned on accelerator mass...
Abstract Between 10,500 and 9000 cal yr BP, δ 18 O values of benthic ostracodes within glaciolacustrine varves from Lake Superior range − to 22‰ PDB. In contrast, coeval ostracode bivalve records the Huron Michigan basins are characterized by extreme variations, ranging that reflect a source is primarily glacial (∼ 20‰ PDB) much higher characteristic regional meteoric 5‰ PDB). Re-evaluated age models for yield more consistent stratigraphy. The striking feature these sharp drop in between...
Strandlines document the former presence of lakes and a sea in east-central North America along southern margin retreating Laurentide Ice Sheet (LIS). The strandlines these formerly level water bodies are uplifted to north provide evidence glacial isostatic adjustment (GIA) Earth’s crust ice load. We compile published ages measurements present elevation location shore features eight major paleo-water from St. Lawrence Valley northern Great Plains digital format as an aid for numerical...
Abstract Seismic-reflection surveys of the Isle Royale sub-basin, central Lake Superior, reveal two large end moraines and associated glacial sediments deposited during last cycle Laurentide Ice Sheet in basin. The directly overlie bedrock are cored with dense, acoustically massive till intercalated down-ice stratified outwash. Till outwash overlain by varves, a lower red unit an upper gray unit. maximum extent late Younger Dryas-age readvance into western Superior basin is uncertain, but it...
Abstract Extreme precipitation events may cause flooding, slope failure, erosion, deposition, and damage to infrastructure over a regional scale, but the impacts of these are often difficult fully characterize. Regional‐scale landscape change occurred during an extreme rain event in June 2012 northeastern Minnesota. Landscape was documented by 8,000 km 2 airborne lidar data collected before after event. Following improved alignment point reducing error using insight from analysis extensive...
Abstract Objective We propose that deepwater Cisco Coregonus artedi (sensu lato ) survived Wisconsin ice advances through introgression with shallow‐water ~65 ka followed by expression of introgressed genomic fragments after the last retreat from Great Lakes ~15 ka. Methods reviewed Glaciation in relation to putative within and employed a phylogeographic approach substantiate locations refugia implications for dispersal ahead advance ice. Result showed Cisco, contrast were very unlikely have...