Case Studies on 2D- and 3D-Time Reverse Modeling of Low-frequency Microtremors - Application to Reservoir Localization

A fast and economically attractive procedure to detect hydrocarbon reservoirs is of main interest for the exploration and development of new oil or gas fields. Several studies at different oil and gas fields around the world have shown spectral anomalies with a high degree of correlation to the location and geometry of hydrocarbon reservoirs. It is reported that the narrow-band low frequency (1.5Hz-6Hz) tremor signals measured at the surface may originate from the reservoirs themselves. However, standard localization techniques fail to localize the signals for real data as one observes continuous tremors rather than single events. Time reverse modeling is a promising technique to reliably localize the so called hydrocarbon microtremors. We show with a numerical feasibility study and real data the potential of such an approach. By using a realistic geologic section we demonstrate with 2D- and 3D-Time reverse modeling that it is possible to localize the origin of tremor-signals.