POLLEN AND ISOTOPIC RECORDS IN LATE HOLOCENE SEDIMENTS FROM LAKE TURKANA, KENYA

Citation
Mu. Mohammed et al., POLLEN AND ISOTOPIC RECORDS IN LATE HOLOCENE SEDIMENTS FROM LAKE TURKANA, KENYA, Palaeogeography, palaeoclimatology, palaeoecology, 119(3-4), 1996, pp. 371-383
Citations number
37
Categorie Soggetti
Paleontology
ISSN journal
00310182
Volume
119
Issue
3-4
Year of publication
1996
Pages
371 - 383
Database
ISI
SICI code
0031-0182(1996)119:3-4<371:PAIRIL>2.0.ZU;2-E
Abstract
A 12 m piston core (LT 84-8P) taken in the northern basin of Lake Turk ana has been dated by 6 AMS radiocarbon dates on large ostracods and a nalysed for its pollen content. During the past 2500 years,the pollen assemblages were dominated by Chenopodiaceae/Amaranthaceae (Cheno/Am) and Gramineae, representing the local pollen signal of the surrounding vegetation under arid conditions. Percentage fluctuations of Cheno/Am are interpreted as reflecting lake level variations in good correspon dance with oxygen isotope from the same core. A rise in lake level is recorded at about 1600 yr B.P., preceded by a relative lowstand during much of the period from 2500 to 1600 yr B.P. The top of the core is e stimated to be about 600 yr old, and shows a shift of unknown duration towards a more humid condition. The high lake level documented in thi s paper roughly coincides with that reconstructed from other cores in the lake based on diatom and carbonate analyses.