Coastline and Dune Evolution along the Great Lakes
Temporally constrained eolian sand signals and their relationship to climate, Oxbow Lake, Saugatuck, Michigan
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Published:July 01, 2014
Interrelationships among late Holocene climate, the dynamics of coastal dunes and sedimentation in adjacent small lakes along coasts of the upper Great Lakes have been studied for over a decade. Nonetheless, many questions remain as to relationships between climate variability and dune activity. The study site is Oxbow Lake, near Saugatuck, Michigan, which formed as an artificial cutoff of the Kalamazoo River in 1906. Stratigraphic control of the infilled western end of the lake is from ground penetrating radar, and lake sediment from Livingstone and Glew cores with age control from 210Pb/137Cs/7Be analysis. The climate data used included Lake Michigan water levels and temperature, precipitation, drought and evaporation data from a weather station 30 km to the south and wind data from buoys on Lake Michigan. Episodic peaks of eolian sand in the lake sediment are interpreted to be sourced from adjacent small parabolic dunes along the shoreline and from a foredune west of the lake. Linear regressions of the climate data and weight percent sand resulted in a variety of correlations, some conflicting, and with uncertain meanings. It was found through visual correlation that peaks in sand correspond with both peaks in water levels of Lake Michigan and the winter Palmer drought severity index. The implications of this research are that dune activity is linked to periods of wet conditions and storminess, contrary to typical eolian environments, but consistent with other studies in temperate coastal dunes along the Great Lakes. Results can be used as a modern analogue for coastal dune activity during times of high lake level.
- alkali metals
- alkaline earth metals
- Allegan County Michigan
- Be-7
- beryllium
- Cenozoic
- cesium
- chronostratigraphy
- clastic sediments
- coastal dunes
- cores
- Cs-137
- dunes
- eolian features
- geophysical methods
- geophysical surveys
- grain size
- Great Lakes
- ground-penetrating radar
- Holocene
- isotopes
- lacustrine environment
- Lake Michigan
- lake sediments
- lead
- lithofacies
- lithostratigraphy
- metals
- Michigan
- Michigan Lower Peninsula
- North America
- paleoclimatology
- Pb-210
- Quaternary
- radar methods
- radioactive isotopes
- sand
- sediment transport
- sediments
- shore features
- size distribution
- surveys
- transport
- United States
- upper Holocene
- wind transport
- Saugatuck Michigan
- Oxbow Lake