Rate estimates for lateral bedrock erosion based on radiocarbon ages, Duck River, Tennessee
Rates of bedrock erosion in ingrown meandering rivers can be inferred from the location of buried relict flood-plain and river-bank surfaces, associated paleosols, and radiocarbon dates. Two independent methods are used to evaluate the long-term rates of limestone bedrock erosion by the Duck River. Radiocarbon dates on samples retrieved from buried Holocene flood-plain and bank surfaces indicate lateral migration of the river bank at average rates of 0.6-1.9 m/100 yr. Such rates agree with lateral bedrock cliff erosion rates of 0.5-1.4 m/100 yr, as determined from a comparison of late Pleistocene and modern bedrock cliff and terrace scarp positions. These results show that lateral bedrock erosion by this river could have occurred coevally with flood-plain and terrace formation and that the resulting evolution of valley meander bends carved into bedrock is similar in many respects to that of channel meanders cut into alluvium. 11 references, 5 figures.
- Research Organization:
- Wright State Univ., Dayton, OH
- OSTI ID:
- 5486844
- Journal Information:
- Geology; (United States), Journal Name: Geology; (United States) Vol. 13:2; ISSN GLGYB
- Country of Publication:
- United States
- Language:
- English
Similar Records
Exposure of late Pleistocene Mississippi River meander-belt facies at Mt. Pleasant, Louisiana
Evidence of Late-Holocene floods in the central Great Plains
Related Subjects
Terrestrial-- Basic Studies-- Radiometric Techniques-- (-1989)
54 ENVIRONMENTAL SCIENCES
AGE ESTIMATION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON 14
CARBON ISOTOPES
CARBONATE ROCKS
CENOZOIC ERA
EROSION
EVEN-EVEN NUCLEI
FEDERAL REGION IV
GEOLOGIC AGES
HYDROLOGY
ISOTOPE DATING
ISOTOPES
LIGHT NUCLEI
LIMESTONE
NORTH AMERICA
NUCLEI
QUATERNARY PERIOD
RADIOISOTOPES
ROCKS
SEDIMENTARY ROCKS
TENNESSEE
USA
YEARS LIVING RADIOISOTOPES