CPC G01V 1/345 (2013.01) [E21B 49/00 (2013.01); G01V 1/003 (2013.01); G01V 1/303 (2013.01); G01V 2210/1295 (2013.01); G01V 2210/1425 (2013.01); G01V 2210/6222 (2013.01); G01V 2210/74 (2013.01)] | 14 Claims |
1. A method of determining a set of first breaks of a seismic dataset generated by a seismic source, comprising:
obtaining the seismic dataset, wherein the seismic dataset comprises a plurality of seismic traces and a provisional first break for each of the plurality of seismic traces;
selecting, using a computer processor, a plurality of proximal picks for each seismic trace, wherein each proximal pick lies within a time window enclosing the provisional first break;
determining, using the computer processor, a near-offset pick for a seismic trace with a shortest offset and sequentially selecting, in order of increasing offset, a first selected trace and determining the near-offset pick for the first selected trace based on proximal picks of the first selected trace and the near-offset pick for at least one seismic trace with a shorter offset than the first selected trace;
determining, using the computer processor, a far-offset pick for a seismic trace with a farthest offset and sequentially selecting, in order of decreasing offset, a second selected trace and determining a far-offset pick for the second selected trace based on the proximal picks of the second selected trace and the far-offset pick for at least one seismic trace with a farther offset than the second selected trace;
determining, using the computer processor, a set of coincident picks based on the near-offset pick and the far-offset pick for each seismic trace;
fitting, using the computer processor, a first break curve to the set of coincident picks;
determining, using the computer processor, the set of first breaks of the seismic dataset based, at least in part, on the first break curve;
determining, using the computer processor, a seismic velocity model based, at least in part, on the set of first breaks of the seismic dataset;
determining, using the computer processor, a seismic image of a subsurface region of interest based, at least in part, on the seismic velocity model;
planning a wellbore trajectory based, at least in part, on the seismic image, and
drilling the wellbore trajectory.
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