Locating oil or gas actively or passively by observing a porous oil and gas saturated system giving off its characteristic resonance response to artificial excitation or ambient background noise, including optional differentiation of oil, gas and water

摘要

#$%^&*AU2009243472B220150604.pdf#####EDITORIAL NOTE 2009243472 Please note that the claim paragraphs before the abstract are not considered to belong to the specification as accepted.10. testing seismograms to identify rock-volume only oscillations based on shear wave effects, 11. selecting from the so gained set of synthetic seismograms a set best fitting the real ones, thereby obtaining the most likely fitting fluid from for oils, gas or water and so differentiating between them. ABSTRACT This patent deals with methods to extract and analyze seismic signals due to resonance phenomena in an enclosed oil, gas, or water reservoir, due to either passive excitation by seismic background noise, or selective active applied excitation, locating thereby the presence of the reservoir by doing qualitative and quantitative estimates via forward modeling. Eight excitation steps are covered. Nine qualitative analysis steps are presented. Several specific techniques are used to relate the actual measurement with a numerical or theoretical model based on specific physical concepts, and so arriving at relevant conclusions about the reservoir. A qualitative survey method and a quantitative method based on a numerical modeling in conjunction with the Monte Carlo method are used to relate the oscillation characteristics to fluid properties. Differentiation between fluids is included. The uniqueness of these methods is that they are directly sensitive to the oil or gas itself, because the resonance effect is only present for a fluid. Gas bubbles can strongly influence results. DRAWINGS