Reducing Uncertainty With Seismic Measurements While Drilling

摘要: This paper discusses both seismic checkshot data inversion and waveform look-ahead imaging while drilling. We investigate the estimation under real-time uncertainties of interval velocity profiles calculated from measurements acquired It is found that checkshots may suffer downhole time-picking errors in addition to an unpredictable clock drift uncertainty. developed a method account for these provide drillers with reliable formation models real time, regardless whether direct arrival times are detected by automated process or picked interpreter uphole once seismograms have been transmitted surface through mud-pulse telemetry. By quantifying posterior interpreted measurements, we then demonstrate: 1) value making waveforms recorded memory available time at 2) benefit accounting standard deviations, which describe errors, case when not available. exemplified application proposed methodology collected deep water Gulf Mexico, inverted consistent comparable ones obtained travel after drilling complete. Finally, study shown combining downhole-to-surface look ahead optimal well steering high-probability hydrocarbon sands.