| Summary: | This thesis presents two new sensors for measuring permeability and acoustic properties on slabbed core samples in the petrophysics laboratory. Prototypes were built to demonstrate that the new techniques are viable. The permeability sensor is the first non-contact, high spatial resolution, permeameter ever to have been developed; it has been called a micro-permeameter. It was calibrated using both synthetic and real rock samples. The collected data were compared with results from the industry-standard CoreLab PDPK-400 mini-permeameter. The comparison shows that the new micro-permeameter is much faster than the CoreLab instrument. In addition, the new micro-permeameter is more sensitive to permeability changes and yet still makes more repeatable measurements. The uniqueness of the new micro-permeameter project resulted in the granting of US patent No. 6715341 (see Appendix D). The acoustic sensor developed is laser-based for the excitation stage only, and piezoelectric-based for the detection stage. The laser was tuned to generate acoustic waves in the rock without harming the rock surface. The new experimental method is comparable with exploration seismic surveys, but unique in the petrophysics laboratory. As a result, seismic software may be used to analyse the collected data. A significant discovery was made that not only was the new laser-acoustic system able to identify the standard direct-wave events, but also it reflected and refracted events never identified in petrophysics laboratory before. The standard velocity measurements for the pressure- wave (Yp) and the shear-wave (Ys) may now be made with a far greater accuracy than is possible with the established single-path method. Furthermore, the accuracy may now be measured statistically, rather than as an estimate. Direct measurements of amplitude-versus-offset (AYO) phenomena, which are impossible with the established method, may now be made. The results could be used to calibrate exploration seismic data, with fewer assumptions than the standard approach.
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