Comparison of uranium-series, radiocarbon, and amino acid data from marine molluscs, Baffin Island, Arctic Canada
- U.S. Geological Survey, Denver, CO
Uranium-series and /sup 14/C dates and the extent of amino acid racemization are reported for 24 marine shell samples from three areas of Baffin Island, Arctic Canada. When the radiometric dates are plotted against the ratio of D-alloisoleucene:L-isoleucene in the shells, five broad age groups are recognized. The uranium-series data indicate that /sup 231/Pa is incompletely retained in most fossil shells and that /sup 230/Th is lost from some of the samples. Therefore, their apparent ages are minimum. However, a few dated samples in each group have yielded useful age results, and the minimum ages of the five groups of samples are estimated as 7,000 to 11,000, greater than or equal to70,000, greater than or equal to136,000, greater than or equal to190,000 and >300,000 yr. Calculated integrated thermal histories based on the epimerization reaction in the mollusc Hiatella arctica Linne give paleotemperature estimates of around -5/sup o/C, compared to the present mean annual air temperature of about -11/sup o/C.
- OSTI ID:
- 5868600
- Journal Information:
- Geology; (United States), Vol. 9:10
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ARCTIC OCEAN
GEOLOGIC HISTORY
MOLLUSCS
ISOTOPE DATING
AMINO ACIDS
CANADA
CARBON 14
PROTACTINIUM 231
QUATERNARY PERIOD
SEDIMENTATION
THORIUM
URANIUM
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ACTINIDES
AGE ESTIMATION
ALPHA DECAY RADIOISOTOPES
ANIMALS
AQUATIC ORGANISMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON ISOTOPES
CARBOXYLIC ACIDS
CENOZOIC ERA
ELEMENTS
EVEN-EVEN NUCLEI
GEOLOGIC AGES
HEAVY NUCLEI
INVERTEBRATES
ISOTOPES
LIGHT NUCLEI
METALS
NORTH AMERICA
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PROTACTINIUM ISOTOPES
RADIOISOTOPES
SEAS
SURFACE WATERS
YEARS LIVING RADIOISOTOPES
580100* - Geology & Hydrology- (-1989)