Estimating the age of formation of lakes: An example from Lake Tanganyika, East African Rift system

Journal Article · Tue Jun 01 04:00:00 EDT 1993 · Geology

DOI:https://doi.org/10.1130/0091-7613(1993)021<0511:ETAOFO>2.3.CO;2· OSTI ID:543374

Cohen, A; Soreghan, M J ^[1]; Scholz, C A ^[2]

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1. Univ. of Arizona, Tucson, AZ (United States)
2. Duke Univ. Marine Lab., Beaufort, NC (United States)

Age estimates for ancient lakes are important for determining their histories and their rates of biotic and tectonic evolution. In the absence of dated core material from the lake`s sedimentary basement, several techniques have been used to generate such age estimates. The most common of these, herein called the reflection seismic-radiocarbon method (RSRM), combines estimates of short-term sediment-accumulation rates derived from radiocarbon-dated cores and depth-to-basement estimates derived from reflection-seismic data at or near the same locality to estimate an age to basement. Age estimates form the RSRM suggest that the structural basins of central Lake Tanganyika began to form between 9 and 12 Ma. Estimates for the northern and southern basins are younger (7 to 8 Ma and 2 to 4 Ma, respectively). The diachroneity of estimates for different segments of the lake is equivocal, and may be due to erosional loss of record in the northern and southern structural basins or to progressive opening of the rift. The RSRM age estimates for Lake Tanganyika are considerably younger than most prior estimates and clarify the extensional history of the western branch of the East African Rift system. 31 refs., 3 figs., 1 tab.

• OSTI ID: 543374
• Journal Information: Geology, Journal Name: Geology Journal Issue: 6 Vol. 21; ISSN 0091-7613; ISSN GLGYBA
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
58 GEOSCIENCES
AGE ESTIMATION
DEMOCRATIC REPUBLIC OF THE CONGO
LAKES
RIFT ZONES
SEISMIC SURVEYS
TECTONICS