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Abstract
Remains of a Holocene drowned forest in southern Lake Huron discovered in 12.5 m of water (164 m above sea level), 4.5 km east of Lexington, Michigan USA (Sanilac site), provided wood to investigate environment and lake history using several proxies. Macrofossil evidence indicates a forest comprised primarily of conifers equivalent to the modern “rich conifer swamp” community, despite generally low regional abundance of these species in pollen records. Ages range from 7095 ± 50 to 6420 ± 70 14C yr BP, but the clustering of stump dates and the development of 2 floating tree-ring chronologies suggest a briefer forest interval of no more than c. 400 years. Dendrochronological analysis indicates an environment with high inter-annual climate variability. Stable-carbon isotope composition falls within the range of modern trees from this region, but the stable-oxygen composition is consistent with warmer conditions than today. Both our tree-ring and isotope data provide support for a warmer environment in this region, consistent with a mid-Holocene thermal maximum. This drowned forest also provides a dated elevation in the Nipissing transgression at about 6420 14C yr BP (7350 cal yr BP) in the southern Lake Huron basin, a few hundred years before reopening of the St. Clair River drainage.
Keywords
Lake Stanley,
tree rings,
stable isotopes,
Lake Huron,
Holocene,
lake levels,
Thuja,
Paleoclimatology,
radiocarbon dating,
climatic changes,
Michigan,
plant communities,
Paleoecology,
Paleobotany,
Paleobiology,
fossil trees,
carbon isotopes,
dendrochronology,
tree-rings,
Lake Huron
Citation
Hunter, R. Douglas; Panyushkina, Irina P.; Leavitt, Steven W.; Wiedenhoeft, Alex C.; Zawiskie, John. 2006. A multiproxy environmental investigation of Holocene wood from a submerged conifer forest in Lake Huron, USA. Quaternary research. Vol. 66 (2006): pages 67-77.
