THE FLUCTUATION OF THE LEVEL OF THE WATER TABLE DUE TO BAROMETRIC CHANGE

Abstract

Fluctuations of the water level in a water table well were observed in which the diurnal and the semi-diurnal were most remarkable. Such fluctuations have a close relationship to those of barometric pressure. The water level fluctuations seem to occur somewhat in advance of barometric changes. It has been found that the ratios of amplitudes become smaller, and the phase advances increase when fluctuations have longer periods. Those phenomena are explained on the basis of the theory of pressure propagation through soil air, in which the permeability of the underground and its effective porosity are estimated as about 4.8 Darcy and 0.3 respectively.