By Nneka Nwogwugwu
Kenyan investigators drilled Lake Magadi as part of the Hominin Sites and Paleolakes and collected deep sediment cores from lake basins in the East African Rift, The East Africa news reports.
They will examine the geochemical record of drill core sediments collected from Lake Magadi, an internally drained, saline and alkaline terminal sump in the south Kenya Rift, that provides a nearly one-million-year paleoenvironmental record from an unusual Rift Valley Lake system.
The drilling project lead investigator, Dan Deocampo of Georgia State University, said: “We are trying to understand how the Earth’s surface environment has changed over the last several million years and how that has impacted early hominin habitats.”
“We are using many different proxies of the ancient environments to understand how the environment has changed, how habitats have changed.”
The researchers also said in their report that geochemical analysis of the Lake Magadi samples showed some of the highest concentrations of elements like molybdenum, arsenic, and vanadium ever reported in lake sediments.
Euxinic conditions occur when the lake water is both anoxic and sulfidic, typically triggered during negative water balance episodes like droughts.
Most molybdenum is used to make alloys and in steel alloys to increase strength, hardness, electrical conductivity and resistance to corrosion and wear. Elevated concentrations of these elements represent times when the lake’s hypolimnion was euxinic — that is, anoxic, saline, and sulfide-rich.
