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  • Virtual sources can yield real results

    R. Calvert

    The Virtual Source (VS) idea is to reconsider receivers of wave energy as virtual sources with a known and controllable output waveform and radiation pattern for a wide range of conditions. This idea allows us to improve what we can do with physical sources and leads to many new possibilities, some described below, and many more to explore. Acoustic waves going through a receiver are measured and recorded in various ways. These measured signals may be filtered to a desired waveform and selectively weighted and summed. This allows us to mathematically build a virtual source with the known desired waveform radiating from our illuminated receiver. Properly designed downhole geophone configurations allow wave energy to pass through the virtual source receiver to the target and scatter back wave energy to this and other receivers. With this in mind, we can mathematically create a source that is as unobtrusive and cheap as a geophone . . .

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2013 Fracturing Technology

2013 Fracturing Technology