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〕 | lat_d = 44 | lat_m = 19 | lat_s = 39 | lat_NS = N | long_d = 87 | long_m = 32 | long_s = 41 | long_EW = W | area_unit = acre | area_imperial = 25 | area_round = 0 | established = 1967 | management_body = Wisconsin Department of Natural Resources | free_type = Unit of | free = Ice Age National Scientific Reserve | map = Wisconsin Locator Map with US.PNG | map_caption = Location of Two Creeks Buried Forest State Natural Area in Wisconsin | map_locator = Wisconsin }} Two Creeks Buried Forest State Natural Area is a site in the Wisconsin State Natural Areas Program and a unit of the Ice Age National Scientific Reserve. The site lies in the northeast corner of Manitowoc County on the shore of Lake Michigan north of Two Creeks, Wisconsin, USA. Exposed on the steep lakeshore is a stratum of floral remains embedded in sediment, which is sandwiched between layers of glacial till. The logs, branches, pine needles, pinecones, moss, and other forest litter have been radiocarbon dated to 11,850 years B.P. This is an important site in geochronology because it firmly establishes the timeframe of advances and retreats during the last glacial period. The lower layer of glacial till was deposited by the Cary substage of the Wisconsin glaciation. The remains in the park prove that a warmer interval followed in which the glacier retreated and a forest of spruce, pine, and hemlock grew. A count of growth rings in the logs produced an average age of 60 years in these trees. Then the climate cooled again and the Valders substage began. A glacial tongue blocked Lake Michigan's drainage, causing the water level to rise and flood the forest, carrying in sediments which buried the forest floor. The glacier proceeded to flow over the forest, flattening it and ultimately depositing another layer of glacial till over it. Two Creeks Buried Forest State Natural Area is open to visitation. There is an historical marker at the location. The site has no trails or displays, but visitors can park in the northwest corner of the site and wander freely across the grounds. Collection of any material is prohibited. ==References== *Black, Robert F. ''Geology of the Ice Age National Scientific Reserve of Wisconsin''. National Park Service Scientific Monograph, 1974. () *Meyer, Thomas, ed. ''Wisconsin, Naturally: A Guide to 150 Great State Natural Areas''. Wisconsin Department of Natural Resources, 2003. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Two Creeks Buried Forest State Natural Area」の詳細全文を読む スポンサード リンク
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