PALAEOSECULAR VARIATION FROM A VANCOUVER-ISLAND STALAGMITE AND COMPARISON WITH CONTEMPORARY NORTH-AMERICAN RECORDS

A record of palaeosecular variation has been obtained from a stalagmit e from Vancouver Island, Canada, spanning the period 16.9 +/- 6.0 to 1 3.3 +/- 2.3 ka. Dating control was provided using the uranium-thorium disequilibrium method. The main magnetic remanence carrier in the spel eothem is a fine-grained magnetite which is thought to be of detrital, rather than chemical, origin. The record is apparently free from any depositional inclination errors and compares well with a contemporaneo us speleothem record obtained from the same cave (Latham et al., 1987) . Good correlation also exists with several North American lacustrine records. The record provides evidence of clockwise looping of the posi tion of the virtual geomagnetic pole over western Canada from about 14 .9 to 13.6 ka, and in the interval from 16.9 to 15.2 ka the data can b e modelled by a stationary, oscillating, inward-pointing source to the north-west of the sampling site.