Paper Summary
Broadband seismic aims to provide a greater richness of both (a), robust low frequencies – ideal for deep structure imaging, and (b), high frequencies – which aid temporal resolution. However, the earth response will act as a frequency filter by attenuating high frequencies at a greater rate than low frequencies, a physical phenomenon described by the quality factor, Q. In this paper we consider effective attenuation, Qeff, which is the inseparable combination of intrinsic attenuation, Qint, and apparent attenuation, Qapp. This paper evaluates the changes in spectral content of broadband seismic versus conventional marine seismic through simple synthetic earth models. Results show that resolution of thin layers of sandstone (~50m) may not be resolved in broadband seismic where values of Qeff are at typical values found in prospective basins such as the North Sea (Europe). In conclusion, this paper suggests that while broadband seismic is desirable, solving for the effects of effective attenuation, Qeff, will be required to prevent a loss of resolution in some geological settings.
