Late Wisconsin and Early Holocene runoff through the upper Ohio River basin
- Virginia Univ., Morgantown, WV (United States). Dept. of Geology and Geography
A tentative absolute chronology is emerging from radiocarbon dates on glacial, alluvial and colluvial sediments in the upper Ohio River basin. Radiocarbon dates for Gallipolis Lock and Dam indicate the river eroded down to its present bedrock floor before 22,400 yr B.P. Data from several sites indicate aggradation began soon after 22,400 yr B.P., coincident with, or just before, a glacier advance into the upper Ohio basin. Sand and gravel aggraded in glaciated tributaries and the main valley, whereas silt, fine sand, and clay accumulated in unglaciated tributaries. Slope instability and colluvial deposition were extensive at this time. Aggradation continued until 25 to 40 m of sediments filled the Ohio River Valley. The paucity of radiocarbon dates prohibits precise determination of when peak aggradation occurred and how that peak related to glacial and climatic events. Although the Laurentide Ice Sheet retreated out of the basin by about 14,000 yr B.P., the river remained braided until at least 13,000 yr B.P., possibly because of slope instability in a cold late Wisconsin climate or the time required for the river to adjust to reduced outwash sediment supply. Coarse late-glacial channel deposits may reflect increased flood discharges after 13,000 B.P. and onset of the transition from a braided system to a meandering channel. However, the upper Ohio River seems not to have taken on its modern morphology until the early Holocene. Most dated overbank deposits on tributaries are younger than 10,000 yr B.P.; most on the Ohio River are younger than 8,500 yr B.P.
- OSTI ID:
- 5689737
- Report Number(s):
- CONF-921058--
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Journal Name: Geological Society of America, Abstracts with Programs; (United States) Vol. 24:7; ISSN GAAPBC; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
Similar Records
History of late glacial flow through the middle Mississippi and Illinois Valleys
A view of late glacial runoff from the lower Mississippi River valley
Related Subjects
580000* -- Geosciences
AGE ESTIMATION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON 14
CARBON ISOTOPES
CENOZOIC ERA
DISASTERS
DRAINAGE
ENVIRONMENTAL TRANSPORT
EROSION
EVEN-EVEN NUCLEI
FLOODS
GEOLOGIC AGES
GLACIERS
ISOTOPE DATING
ISOTOPES
LIGHT NUCLEI
MASS TRANSFER
MORPHOLOGY
NUCLEI
OHIO RIVER
OHIO VALLEY REGION
QUATERNARY PERIOD
RADIOISOTOPES
RIVERS
RUNOFF
SEDIMENTS
STREAMS
SURFACE WATERS
YEARS LIVING RADIOISOTOPES