METHOD FOR DOWNHOLE LOGGING

摘要

A method and apparatus for measuring the properties such as permeability of the rock surrounding a borehole in which a directional seismic or sonic sign al is generated downhole and propagated into the surrounding formation to generate an electrokinetic signal and the focus of the seismic signal is mov ed in three dimensions in the surrounding rock by physically moving the source or by having two seismic sources which generate oscillating seismic signals at different frequencies and the focus of the seismic signal is varied by wave interference or wave interaction.