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
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.