Dr Henry Lamb
Investigations of Quaternary palaeoclimate currently underway at the Institute of Earth Studies make use of ostracod palaeoecology and geochemistry. The shells are often well preserved in lake sediments, their varying abundances providing a record of the changing lacustrine environment. Trace amounts of strontium and magnesium, and ratios of stable carbon and oxygen isotopes in the calcite shells, reflect lake-water conditions at the time of shell formation. Because a lake's chemical and isotopic status is controlled to a large degree by precipitation to the lake and its catchment, evaporative water loss, and its groundwater budget, geochemical analysis of the ostracod valves is a way of determining climatic history. Current projects include work on Holocene climate changes in Morocco (eg Lamb et al 1995, Nature 373, 134-137), and Ethiopia.
These projects make use of the unique combination of expertise and facilities available in the Institute of Earth Studies, namely the Micropalaeontology Unit headed by Professor Robin Whatley, and the Inductively-coupled Plasma Mass Spectrometer run by Dr Bill Perkins and Dr Nick Pearce. Stable isotope analyses will be carried out at NERC's Isotope Geochemical Laboratory, under the supervision of Dr Melanie Leng, a former Institute research student.