On the compilation of the map of contemporary vertical crustal movements in canada

Abstract

Vaníček, P. and Nagy, D., 1981. On the compilation of the map of contemporary vertical crustal movements in Canada. In: P. Vyskočil, R. Green and H. Mälzer (Editors), Recent Crustal Movements, 1979. Tectonophysics, 71: 75–86. The first vertical movement map of Canada was compiled from 5046 revelled segments, 39 pairs of water gauge data and trends at 47 tide gauge stations. The country was divided into 9 regions and polynomial surfaces of order 2, 3 and 4 were calculated by the method of least squares for each region to obtain representations of the recent vertical movements. The computations commenced at the east and west coasts and progressed inwards to the central region. Tide gauge trends, calculated from monthly means, provided the initial vertical control; then the predicted values in overlap areas were used as “control” values to obtain subsequent solutions. The final solutions for the various orders of surface were compiled from the 9 overlapping solutions. The 3rd-order surface represents the available data best. This solution is in agreement with the results and models presented by other investigators for uplift in the Yukon and northern B.C., for uplift in the Great Lakes region and for subsidence in the Bay of Fundy. Subsidence in the Prairies, based on the available limited data-set requires further investigation. Contribution of the Earth Physics Branch No. 878 © 1981, Elsevier Scientific Publishing Company