P. Sailhac et G. Marquis, Analytic potentials for the forward and inverse modeling of SP anomalies caused by subsurface fluid flow, GEOPHYS R L, 28(9), 2001, pp. 1851-1854
Classical interpretation techniques developed primarily for gravity and mag
netic data have been adapted to electric self-potential (SP) data. From a r
ecently developed wavelet-based technique for potential field interpretatio
n, we propose a novel approach for the forward and inverse modeling of SP a
nomalies caused by subsurface fluid flow. We use analytic. signals and wave
lets associated with the electric and fluid flow potentials. Fluid flow sin
gularities have typical signatures in the wavelet-domain SP data that can b
e used in the inversion scheme. For cases where electrokinetics is unambigu
ously the origin of SP anomalies, our interpretation method provides key pa
rameters of the subsurface fluid flow (e.g. position, geometry, flow rate).
To illustrate the theory, we consider synthetic 2D flows for which analyti
c solutions exist. and actual SP data acquired around the Vulcarolo fissure
on Mount Etna that show sources between 3 to 18 m depths.