Absolute palaeointensity of Oligocene ( 28 - 30 Ma ) lava flows from the Kerguelen Archipelago ( southern Indian Ocean )
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چکیده
SUMMARY We report palaeointensity estimates obtained from three Oligocene volcanic sections from the Kerguelen Archipelago (Mont des Ruches, Mont des Tempêtes, and Mont Rabouilì ere). Of 402 available samples, 102 were suitable for a palaeofield strength determination after a preliminary selection, among which 49 provide a reliable estimate. Application of strict a posteriori criteria make us confident about the quality of the 12 new mean-flow determinations, which are the first reliable data available for the Kerguelen Archipelago. The Virtual Dipole Moments (VDM) calculated for these flows vary from 2.78 to 9.47 10 22 Am 2 with an arithmetic mean value of 6.15±2.1 10 22 Am 2 .
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تاریخ انتشار 2003