Free cam sex no regist - Archaeomagnetic dating example

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The sampling of Kilns 14858, 10906, 1143 was carried out in October and November 1994 and analysed by Geo Quest Associates in 1995.Each feature was first carefully examined to identify areas that were evidently . This technique employs a 25mm, flanged plastic disc to act as a field orientation reference, sample label and specimen holder inside the laboratory magnetometer.Finally, geomagnetic orientation arrows were marked using a Nautech fluxgate compass, along with a specimen code (it was not possible to use a sun compass at the time of sampling.) The set of orientation arrows were finally checked for parallelism to test for errors due to the bulk magnetisation within each feature; no significant flux distortion was detected in any of the kilns.

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A pilot specimen from each kiln, with typical NRM characteristics, was demagnetised incrementally, up to a peak alternating field of 30, 50 or 80m T and the changes in remanence recorded in order to identify the components of remanence and their stability (Figures 704, 709 and 710).

From a study of the behaviour of the pilot samples, an alternating field of 2.5m T or 5m T was chosen which would provide for the optimum removal of secondary components of magnetisation in the remaining samples.

Finally, the samples were cut with a diamond saw until each button retained a volume that fitted the standard 25x25mm specimen holder inside the archaeomagnetic magnetometer.

The natural remanent magnetisation (NRM) of all the samples was measured in a Molspin fluxgate spinner magnetometer (Molyneux 1971) with a minimum sensitivity of around 5x10-9Am2.

Remanence directions were corrected for the local geomagnetic variation using data published by the British Geological Survey and the vectors are listed in Table 195 (.csv) plotted on the stereograms of Figures 703, 707 and 708.

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