14C Age Corrections in Antarctic Lake Sediments Inferred from Geochemistry
Author
Zale, RolfIssue Date
1994-01-01Keywords
lacustrine sedimentationguano
Lake Boeckella
Pygoscelis adeliae
Sphenisciformes
Antarctic Peninsula
trace elements
corrections
Antarctica
sedimentation
mathematical methods
concentration
models
glacial geology
deglaciation
Chordata
Tetrapoda
Vertebrata
Aves
glaciation
organic residues
sediments
C 14
carbon
dates
isotopes
radioactive isotopes
absolute age
Metadata
Show full item recordCitation
Zale, R. (1994). 14C age corrections in Antarctic lake sediments inferred from geochemistry. Radiocarbon, 36(2), 173-185.Journal
RadiocarbonAdditional Links
http://radiocarbon.webhost.uits.arizona.edu/Abstract
Sediment from Lake Boeckella, Antarctic Peninsula, is richer in Ca, Cd, Cu, P, Sr and Zn than that of six other lakes in the area. The elements originate from Adélie penguin (Pygoscelis adeliae) guano on the lake shores. Changing Cu and P concentrations in the lake sediment are used as a proxy for penguin influence on the lake sediment from ca. 5850 BP to Present. A 14C dating model suggests that the 14C correction factor in the lake sediments depends on the penguin proxy, the apparent age of the penguin guano and the amount of particulate carbon originating from the carbon-bearing shales in the watershed. Glacial meltwater and dissolved carbonates do not contain enough "old" carbon to contribute significantly to the correction factor. Ages corrected with the 14C dating model agree with the depth vs. age curve based on independently 14C-dated tephra horizons. The reservoir effect has been constant since at least 5800 BP, implying long-term stability of the currents and water masses in the area. The existing chronology for Lake Boeckella has been recalculated. The period of glacial advance, previously thought to have culminated at 5000 BP, is now thought to have culminated at 4700 BP; deglaciatlon of the area is thought to have occurred at 6300 BP instead of 8680 BP.Type
Articletext
Language
enISSN
0033-8222ae974a485f413a2113503eed53cd6c53
10.1017/S0033822200040480