9617897 Channell This grant provides $161,248 as one-half support of the costs of acquiring a high resolution cryogenic magnetometer for marine and lacustrine paleomagnetic investigations of regional and global climate change and studies of the secular variation of the relative paleointensity of the Earth's geomagnetic field. Specifically, the University of Florida will acquire a new generation 2-G Enterprises model 755 u-channel cryogenic magnetometer. This instrument provides the capability to rapidly measure the magnetic properties of 1.5 m sections of u-channels taken from piston or gravity cores with high-resolution and high sensitivity using sophisticated DC SQUIDS that afford over an order of magnitude greater sensitivity than the last generation of machines equipped with radio frequency (Rf) SQUIDS. In addition, the Model 755 is equipped with in-line alternating field demagnetization coils and a pulse magnetizer such that measurement of several magnetic properties of the core can be conducted in a single operation, eliminating possible positioning errors during sample transfer to different instruments and allowing long periods of unattended operation. Paleomagnetic analyses of long records of sediment cores collected during ODP cruises to the North and South Atlantic will be conducted in an attempt to better correlate the paleoclimatic signals recorded in these sediments through both grain size, textural and lithologic variations and to better understand the secular variability in the Earth's geomagnetic field as recorded by the relative paleointensity of magnetic minerals within these cores. The recent decision of ODP to allow u-channel sampling of the archive half of piston and gravity cores represents a veritable flood of marine sediment samples waiting to be analyzed and is sure to keep the paleomagnetic community busy for the foreseeable future. Acquisition of a 2-G Model 755 u-channel magnetometer by the University of Florida will be only the second of its kind within the United States (the other is at UC-Davis under the direction of Dr. Ken Verosub) and thus will represent a valuable regional and national facility for the study of environmental paleomagnetism. ***
