Viability assessment of integrated P- and S-wave surveys using ultrasound

Abstract

Potential of, integrated geophysical, especially P- and S-wave combined near surface surveys, is assessed; demonstrated with use of sparingly, reduced chronographic i. e., time and velocity, (1 MHz) ultrasonic imaged data. Case of aqueous and non-aqueous, predominantly, fossil fuel origins spills seepage within near-surface geology is examined in terms of evaluation of possible complexities of fluids and surrounding interactions; which are experimentally simulated embodied as flow components of an immiscible displacement process. Such processes are understood and studied widely, within various, especially near-field geo- and engineering including environmental and also geo-disaster contexts. Interesting relevant scenarios, including aspects, of geological complexity of well known geographical locations while their subjugation also to various, whether natural or anthropogenic, stressors are presented alongside pertinent theory for better grasp, including plausibility, of methodology and inferring. Experimental analogues and geometrical constraints are explained in detail. Ultrasonic P- and S-wave, data in relevant context, also verified analytically, are comprehensively evaluated. S-wave data not only corroborates P-wave data attributes in time-space localization of displaced, from displacing phase, including a “dim spot”, an interesting artifact corresponding to interface (or mixed phase) region, S-wave also manifested other elastic and thermo-mechanical characteristics of the same feature. Further a flow rate, especially, that of injection, control or dependence of a planned displacement process was confirmed, for example if required in tracer and remedial studies. S-waves characteristic suitability to reveal other fluid-fluid and fluid-solid interaction peculiarities at micro and possibly at nano scale, as amplitude effects, is foreseen to assume significant promise.