Variability of Lake Michigan water level during the past 1000 years reconstructed through optical dating of a coastal strandplain

Abstract

Post Nipissing-phase strandplains of the Great Lakes reflect late-Holocene water levels that are linked to climate variability, glacial isostasy, and changes in basin hydrology. This study examines a strandplain sequence at Bailey’s Harbor, Door County, Wisconsin, along Lake Michigan, which contains a record of water-level variations during the past 1000 years, following the separation of the Lake Michigan-Huron basin from the Lake Superior basin. Vibracores are used to define the current elevation of the foreshore facies in 25 preserved beach ridges. Optical ages for five individual beach ridges are compared with radiocarbon ages on basal peats from nine swales collected in a previous study. The optical chronology yields a ridge formation/preservation rate of 30 ± 2 yr/ridge similar to that of previous assessments. This study further demonstrates the efficacy of optical dating for deciphering late-Holocene beach-ridge sequences, providing multidecadal resolution. Lake level meets or exceeds, by at least 0.5 m, historic metrics at c. AD 1125—1225. The maximum water level after c. AD 1225 is comparable with that recorded by the instrumental data. There is a noticeable high lake level from c. AD 1560 to 1725. Dating of additional sites along Lake Michigan is required to establish local rates of glacio-isostatic adjustment, identify possible erosion of the outlets and to resolve lake-level records for individual lakes following the separation of the upper Great Lakes currently constrained to have occurred c. 2400 to 1200 years ago.

Dune formation on late Holocene sandy bay barriers along Lake Michigan's Door Peninsula: The importance of increased sediment supply following the Nipissing and Algoma high lake-level phases

“…In low gradient embayments, which dominate the Great Lakes, bay barrier morphology is highly influenced by sediment supply. Both barriers and strandplains are preserved along shorelines throughout the Great Lakes, and these features, especially strandplains, have proven crucial for reconstructing middle to late Holocene lake-level fluctuations in the Lake Michigan (e.g., Thompson and Baedke, 1995;Dott and Mickelson, 1995;Baedke and Thompson, 2000;Argyilan et al, 2010;Thompson et al, 2011) and Superior basins (Johnston et al, 2012). Because they are commonly dominated by sand, barriers are frequently capped with varying amounts of eolian sand, as are the three barriers at our study sites in the Door Peninsula.…”

A large‐scale medieval dam‐lake cascade in central Europe: Water level dynamics of the Havel River, Berlin–Brandenburg region, Germany

“…The given calibrated 14 C ages represent the age ranges with the highest corresponding probability (cf. Argyilan, Forman and Thompson, 2010).…”

“…Radiocarbon data for the Havel River sections. The calibrated 14 C ages (two sigma deviation) given in the text and figures represent the age ranges with the highest corresponding probability (cf Argyilan et al, 2010). indicated in the table by bold numbers…”

Palaeohydrographic reconstructions from strandplains of beach ridges in the Laurentian Great Lakes

“…becoming the standard procedure for this type of research in the Great Lakes region (Argyilan et al 2010;Johnston et al 2012). One of the more interesting events that strandplain data has helped refine is the separation of Lake Superior from lakes Michigan and Huron.…”