|dc.contributor.author||Owen, Richard Bernhart||
|dc.description.abstract||Quaternary lacustrine sediments are described from
three contrasting areas within the Kenya Rift Valley.
Descriptions are given of the mid-Pleistocene Olorgesailie
Formation at Olorgesailie. (southern-, Kenya Rift Valley),
a series of lacustrine sediments deposited between the
mid-Miocene and present in the Baringo District (central
Kenya Rift Valley) and finally of Quaternary'(largely
Holocene) deposits at East Turkana (northern Kenya Rift
Valley). A wide range of environments are represented by
these deposits including offshore and littoral lacustrine,
deltaic and alluvial situations. Emphasis is placed on the
examination of lacustrine and lake marginal sediments.
Diatom assemblages found. in these deposits are described
for the first time. These have 'been studied using optical
and scanning electron microscopy. The. relationships
between diatom assemblages and sedimentary facies are
examined and evolutionary trends in certain diatoms are
discussed. The contemporary ecology of diatoms at East
Turkana is discussed and a review is given of diatom
ecology and lake classification in East Africa. Diatoms
are used to indicate transgression-regression. cycles
during the Holocene, and palaeoecological conditions
through the Quaternary. Mapping in conjunction with some
altimetric data is used to indicate the location, extent
and height of several Holocene lacustrine still-stands.
Geochemical and sedimentological data is presented for
the Holocene deposits at East Turkana and in the Baringo
District. Several erosional and depositional processes
operating at East Turkana are briefly discussed. A
classification of Holocene environments at East T»rksna
The palaeogeography of the northern Kenya Rift Valley
and the development of diatom floras during the Holocene
is discussed. Data presented here and in the literature
is considered and reviewed from a palaeoclimatic viewpoint.
The development of Lakes Turkana, Baringo and Bogoria
through the Quaternary are also considered.
Conclusions are drawn as to the value of diatoms in
palaeoecology and stratigraphy.||en_US
|dc.title||Quaternary diatomaceous sediments and the geological evolution of lakes, Turkana, Baringo and Bogoria Kenya Rift Valley.||en_US
|dc.rights.holder||The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author||