Portal de Periódicos da CAPES

Late Wisconsinan-early Holocene riparian paleoenvironment in southeastern Iowa

1993; Geological Society of America; Volume: 105; Issue: 2 Linguagem: Inglês

10.1130/0016-7606(1993)105 2.3.co;2

1943-2674

Richard G. Baker, E. Arthur Bettis, D. G. Horton,

Botany, Ecology, and Taxonomy Studies

Research Article| February 01, 1993 Late Wisconsinan-early Holocene riparian paleoenvironment in southeastern Iowa R. G. BAKER; R. G. BAKER 1Department of Geology, University of Iowa, Iowa City, Iowa 52242 Search for other works by this author on: GSW Google Scholar E. A. BETTIS, III; E. A. BETTIS, III 2Iowa Department of Natural Resources, Geological Survey Bureau, 109 Trowbridge Hall, Iowa City, Iowa 52242-1319 Search for other works by this author on: GSW Google Scholar D. G. HORTON D. G. HORTON 3Department of Botany, University of Iowa, Iowa City, Iowa 52242 Search for other works by this author on: GSW Google Scholar Author and Article Information R. G. BAKER 1Department of Geology, University of Iowa, Iowa City, Iowa 52242 E. A. BETTIS, III 2Iowa Department of Natural Resources, Geological Survey Bureau, 109 Trowbridge Hall, Iowa City, Iowa 52242-1319 D. G. HORTON 3Department of Botany, University of Iowa, Iowa City, Iowa 52242 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1993) 105 (2): 206–212. https://doi.org/10.1130/0016-7606(1993)105 2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation R. G. BAKER, E. A. BETTIS, D. G. HORTON; Late Wisconsinan-early Holocene riparian paleoenvironment in southeastern Iowa. GSA Bulletin 1993;; 105 (2): 206–212. doi: https://doi.org/10.1130/0016-7606(1993)105 2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The lithostratigraphy, radiocarbon ages, and pollen and plant macrofossil assemblages in a low terrace on the Iowa River beyond the Wisconsinan glacial boundary reveal regional alluvial relationships and indicate that valleys were important corridors during vegetational change in the Midwest. Basal pebbly sands probably represent a valley train from a central Iowa glacial advance ∼25,000 to ∼21,000 yr B.P. Overlying organic silts indicate low energy conditions from ∼21,000 to ∼15,000 yr B.P. Pebbly sands of an upper valley train were deposited from ∼14,000 yr B.P. until 10,000 yr B.P., about 1,500 yr after the Des Moines Lobe had retreated out of the Iowa River Basin.Pollen and plant macrofossils from the top of the upper pebbly sands indicate that the area was covered by mixed conifer-hardwood forest taxa whose pollen percentages do not match those predicted by models of vegetational change in eastern North America. Boreal elements with general distribution over 500 km to the north at 10,000 yr B.P. persisted in peatland habitats. The valley environment contained a variety of edaphic and microctimatic conditions that supported diverse plant communities. During glacial-interglacial transitions, medium to large valleys served as migration corridors for plant taxa and harbored riparian communities without modern analogs. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.