Open AccessGroundwater microtemperature and strain
Author(s) -
Furuya Itsuo,
Shimamurat Hideki
Publication year - 1988
Publication title -
geophysical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0952-4592
DOI - 10.1111/j.1365-246x.1988.tb05905.x
Subject(s) - groundwater , borehole , geology , tectonics , strain (injury) , high resolution , seismology , period (music) , mineralogy , geomorphology , geotechnical engineering , remote sensing , medicine , physics , acoustics
Summary Groundwater temperatures were measured in deep boreholes of the Tokai District (an earthquake‐prone region in central Japan) with precise thermometers. Observed temperatures have a resolution of better than 1 m°C, and were made simultaneously with observations of crustal strain. Sharp peaks of periods about 12 and 24 h were found in the fine spectra of groundwater temperature. The 12 h‐period components were found to be of tectonic origin, although 24 h components are of artificial origin, e.g. water pumping. At some stations, the groundwater temperature change is explained by the adiabatic temperature change of either water or rock. The water temperature observation sites are grouped by the phase differences of the 12 h‐period variations. This classification coincides well with the independent grouping obtained according to the resemblance of the strain change.