Differential Acoustic Spectroscopy for Low Frequency Laboratory Measurement of Compressibility and Attenuation
Event name: 24th European Meeting of Environmental and Engineering Geophysics
Session: New Technologies, Developments and Research Trends I
Publication date: 09 September 2018
Info: Extended abstract, PDF ( 1.02Mb )
Price: € 20
Differential Acoustic Resonance Spectroscopy (DARS) was developed as a laboratory method for measuring compressibility and attenuation of small samples of materials at low acoustic frequencies. The DARS concept begins with a baseline measurement of resonance frequency and resonance linewidth of a fluid-filled but otherwise empty cavity. When a small sample of rock or other material is placed inside the cavity, shifts in resonance frequency and linewidth occur. The changes in resonance can be inverted for sample compressibility and attenuation. Previous DARS studies focussed on the estimation of compressibility. In this paper, I report the first quantitative estimates of attenuation (Q) from the DARS system. The paper begins with a brief review of the DARS concept, followed by a summary of the DARS theory developed to support Q analysis, and finally measurements and analysis of non-porous and porous samples.