Aligning microseismic reflections for imaging

Aligning microseismic reflections for imaging

Noha S. Farghal and Stewart A. Levin

Abstract:

Microseismic data are not created ready for imaging. They can be extremely noisy and it is not a straightforward task identifying reflections. In a previous work, we were able to use multiplets or events of the same waveform to identify some reflections. However, realizing that reflections were weaker on the stack than they are on the individual seismograms, we inferred we had a misalignment issue between the different seismograms. In this work, we use fractional shifts and receiver-by-receiver shifting to align seismograms more effectively. We also investigate some aspects of multiplets and how they are related to each other in space and time, as well test the use of cross correlations of P-direct arrivals with whole seismograms to identify the unfound P-reflections.