CPC E21B 49/00 (2013.01) [G01V 1/50 (2013.01); G01V 2210/1299 (2013.01); G01V 2210/1429 (2013.01); G01V 2210/47 (2013.01); G01V 2210/6222 (2013.01)] | 18 Claims |
1. A method of determining a drilling-induced rock damage map, comprising:
obtaining, using a sonic tool, a sonic dataset comprising a set of sonic waveforms recorded at each of a plurality of axial source positions along an axis of a wellbore,
wherein the sonic tool comprises at least one sonic source and a plurality of sonic receivers, and
wherein each of the set of sonic waveforms comprises a recording, by one of the plurality of sonic receivers, of sonic waves emitted by the sonic source;
determining, using a slowness time coherence method, a log of a P-wave slowness from the sonic dataset;
determining, using a tomographic method, a map of a P-wave velocity from the sonic dataset; and
determining the drilling-induced rock damage map by subtracting the log of the P-wave slowness from the map of the P-wave velocity at a plurality of depths along the axis of the wellbore.
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