SGER: Rock Magnetism and Paleomagnetism of Corals From Pacific Volcanic Islands: A Feasability Study

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The possibility of getting high-resolution paleomagnetic records of the geomagnetic field from pre-observatory times has been an aim of researchers since the early days of paleomagnetism. Corals afford the possibility of such records. These records would have an enormous impact because at least in direction and even possibly in relative intensity they would be like observatory records. For short periods of time throughout the tens of thousands of years for which dated coral records are available we could have detailed records of the field. The rock magnetic properties of corals have already been used for environmental purposes and this appears to be another possible application of coral magnetism. For example, it may prove an excellent method of dating sequences of volcanic activity.Several years ago, preliminary studies with corals from the Bahamas were attempted, but the combination of the sensitivity limits of instruments at that time and probably the unfortunate choice of corals that were not from volcanic islands precluded satisfactory paleomagnetic records. Recently, studies of corals from the Hawaiian Islands, from the Solomon Islands and from New Ireland have been undertaken. These have demonstrated that modern instrumentation provides the possibility of successful measurement of the paleomagnetic record of corals from these volcanic environments. The next steps are to investigate the fidelity of the records and the magnetic material that carries these records from different types of corals, which will be accomplished with this SGER award.