The potential for U-Pb Dating of Coprolites, Hartford Basin, Connecticut
نویسنده
چکیده
There is a great need for more precise absolute ages for sedimentary rocks. We have been actively involved in developing techniques to directly date sedimentary rocks, rather than using associated igneous rocks, or using relative dating techniques. Sedimentary phosphate nodules (i.e. coprolites) are ideal candidates for absolute dating of sedimentary rocks. Phosphates occur commonly within the rock record, they are composed of francolite which precipitates authigenically early in the diagenetic sequence, and they are enriched in radiogenic Pb. We can vastly improve the resolution of the rock record by dating the time of sedimentation and placing absolute date constraints on the existing relative age boundaries.
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