OXYGEN ISOTOPIC COMPOSITION OF FOSSIL MAMMAL BONES OF HOLOCENE AGE - PALEOCLIMATOLOGICAL CONSIDERATIONS

The existence of a direct quantitative relationship between the oxygen isotopic composition of mammal bone phosphate and the mean oxygen isotopic composition of local meteoric water has been demonstrated by several papers published during the last decade. The measurements of delta-O-18(PO43-)-values in fossil mammal bones represent a potential tool for quantitative palaeohydrological and palaeoclimatological studies. About 90 samples of fossil mammal bones of Holocene age were collected from eight different locations in Italy and measured for their delta-O-18(PO43-). The delta-O-18 of the environmental palaeowaters was calculated from these results by means of the existing equations. The data obtained correspond to qualitative palaeontological and palaeobotanical considerations and their palaeoclimatological implications. These results confirm the potential of the method and support its reliability for quantitative studies in continental areas even though care must be taken in the interpretation of the data obtained to avoid misinterpretations and inappropriate conclusions. The reconstruction of detailed and precise environmental conditions should thus be possible wherever fossil mammal bones of known age may be obtained, at least in the case of the late Quaternary age or at any rate where bones have not undergone diagenetic effects.