Open AccessA survey of Earth strain tides in Great Britain
Author(s) -
Evans Russ,
Beavan John,
Bilham Roger,
King Geoffrey
Publication year - 1979
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1979.tb03776.x
Subject(s) - admittance , geology , strain (injury) , geodesy , geophysics , earth surface , wavelength , physics , optics , medicine , quantum mechanics , electrical impedance
Summary . We report 35 measurements of Earth strain tides at 16 near‐surface sites in Great Britain. This is the first widespread survey undertaken specifically to examine the problem of the inhomogeneity of elastic strain fields near the Earth's surface. Some sites were instrumented intensively in order to examine variations of tidal admittance over distances of several hundred metres, while measurements from single instruments at other sites were compared with theoretically predicted strain tides. After allowing for cavity and topographic effects, our data show variations of up to 50 per cent in tidal admittance. We interpret such large anomalies as being due to variations in the regional elastic parameters of wavelength about a 100 m or less. The data indicate that strain measurements from single instrument sites must be interpreted with caution.