Piezoelectric and a-axes fabric along a quartz vein

Abstract Conversion of seismic energy to radio emissions in geological environments associated with quartz-rich rocks has long been reported in Soviet literature. Seismoelectric signals with the same characteristics have also been detected in recent field experiments in Canada and Australia. While some investigators consider the possible piezoelectric fabric of quartz-bearing rocks as a source for these signals, the mere existence of a natural piezoelectric fabric has been disputed by others owing to absence of reported analytical data at a satisfactorily large scale. A new observation has been made on the consistency of piezoelectric polarity on distinct cubic samples with common orientations from separated points along a quartz vein. The data strongly suggest the existence of a piezoelectric fabric at large scale. Crystallographic data from neutron diffraction texture analysis independently suggest the presence of a quasi-homogeneous fabric of a -axes (which are the piezoelectric axes of quartz). The piezoelectrically polarizable fabric of the rock at large scale makes it an attractive target for seismoelectric exploration and a possible source for some radio emissions associated with earthquakes.

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