TitleMulti-component approach to understanding modern sedimentation in the North Basin of Lake Turkana, Kenya
NameBeck, Catherine C. (author), Feibel, Craig S (chair), Ashley, Gail M (internal member), Fan Reinfelder, Ying (internal member), Rutgers University, Graduate School - New Brunswick,
Rudolf, Lake (Kenya and Ethiopia),
Sedimentation and deposition—Research--Rudolf, Lake (Kenya and Ethiopia),
Settling basins--Rudolf, Lake (Kenya and Ethiopia)
DescriptionThe North Basin of Lake Turkana is a detritally-dominated, highly variable depositional environment that receives contributions from the perennial Omo River as well as ephemeral streams such as the Ileret and Tulu Bor Rivers. Only through understanding of the behaviors and impacts of these two distinct fluvial styles can modern sedimentation in the North Basin be realistically characterized. Four short cores from the Ileret and Tulu Bor deltas were compared with bulk fluvial channel sand samples from each system to study differences in sediment mineralogy indicative of source lithology. These data were used to document how ephemeral, flashy-discharge flooding events are preserved in the sedimentary record of Lake Turkana. Processes such as sublacustrine wave reworking and in channel eolian reworking were examined in detail to gain more insight into how post-depositional processes alter the sedimentary record. The short cores are interpreted to represent one flooding event, with detrital clays settling out of suspension for the majority of the year when these rivers are not flowing. This study showed that ephemeral rivers make significant, localized contributions to the basin and as much as 51 cm of sediment can be deposited during one flooding event. The localized nature of these depocenters makes lake-wide correlations difficult across Lake Turkana. However, by being able to identify and distinguish between localized deposition and larger, basin-wide processes like Omo River flood plumes, it may one day be possible to link records from the North and South Basins of Lake Turkana. By connecting modern sedimentation to documented fluvial discharge events and climate fluctuation producing lake level rises and falls, palaeosedimentary records from the Holocene can be deciphered, giving valuable information about the history of Lake Turkana and the ecosystems that depend upon it.
NoteIncludes bibliographical references
Noteby Catherine C. Beck
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.