Can full waveform refraction imaging overcome the century-long impasse at the first breaks?

Summary

The signal-to-noise ratios (SNR) of the first arrivals are a function of the source-to-receiver distance and the head wave coefficient (HWC), the refraction analogue of the reflection coefficient. In turn, the precision of the first break traveltimes is a function of the SNR.

Stacking with the refraction convolution section (RCS) can significantly reduce the effects of geometrical spreading. However, the effects of the HWC still remain.

The time models of the base of the weathering computed with the common reciprocal method are comparable to those computed with the RCS. However, only the RCS is able to detect small thrusts within the Fresnel zone.

• first breaks
• precision
• signal-to-noise
• RCS