Acquisition of a Paleomagnetics Laboratory at Institute of Human Origins

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With National Science Foundation support Dr. Paul Renee and his collaborators will establish a paleomagnetic dating laboratory at the Institute of Human Origins in Berkeley California. They will obtain both cryogenic and spinner magnetometers and house them in a magnetically shielded space. The cryogenic magnetometer will have automated alternating field demagnetization and measurement capability. The laboratory also will feature a conventional tumbling AF demagnetizer and a thermal demagnetization oven, magnetic susceptibility bridge and extensive computational and graphics capabilities. The facility will conduct a number of research projects, many of which relate to paleoanthropological investigations. These include refinement of the paleomagnetic time scale and the dating of samples from sites which have yielded archaeological and fossil hominid remains. Scientists have made use of the fact that the earth's magnetic field periodically reverses. Research over many years has produced a sequence of these reversals and determined the approximate age of each. Because iron particles in sediments align with the earth's magnetic field at time of deposition, they in essence provide a compass and scientists can sample geological sections and determine the position of the earth's magnetic pole at particular moments in time. Through reference to a dated master sequence, approximate age can then be determined. This procedure has proven invaluable to geologists, paleoanthropologists and other researchers who wish to date specific events in the past. Currently sufficient laboratory capacity does not exist in the United States to meet demand and the establishment of a facility at the Institute for Human Origins will help to remedy the situation. This project is important for several reasons. Research conducted at the laboratory will help to refine paleomagnetic dating by providing more accurate dates for individual reversals. Samples dated by the laboratory will help to answer a number of pressing scientific questions.