CREWES participated in two collaborative seismic surveys that were conducted in New Zealand in early 2016. The target of interest in the Whataroa valley (South Island) is the Alpine Fault, which forms part of the boundary between the Australian and Pacific Plates in southern New Zealand, and has the potential to produce M8+ earthquakes. The Deep Fault Drilling Project (DFDP) drilled and instrumented borehole DFDP-2b prior to the seismic program. The Hauraki Rift survey (North Island) crossed the northern Kerepehi fault, which has previously been inferred from gravity data. The Kerepehi fault is considered to be active, and is thought to have produced M6+ earthquakes in the past. The primary objective of both programs was to better define seismic velocities and geometries of faults that are known to be earthquake risks. Initial processing of surface seismic data has provided relatively good images of sediments, the base of sediments and, we believe, the Alpine and Kerepehi faults.

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Seismic characterization of the Devonian Nisku Formation in the Wabamun area, Alberta, Canada has revealed two primary groups of anomalies. The first group is interpreted to be footprints of geological discontinuities which are induced by dissolution and karsting in a geologic formation shallower in the stratigraphy. Even though there is no evidence to indicate that the integrity of the Nisku Formation or the overlying caprock has been compromised, such geologic discontinuities should be taken into consideration if supercritical CO 2 were to be injected into the Nisku Formation. The second group is interpreted to be due to contrasts in lithology and/or porosity of the Nisku Formation. This interpretation is supported by constraints provided by well control and by seismic modeling. Finally, our analysis has identified favorable low-impedance, potentially high-porosity, locations that could be developed for a CO 2 injection site.

A method for receiver statics correction of converted waves (PS-waves) is proposed here. It is based on the observation that the static time delay on PS-wave events between two adjacent receivers, after the source statics correction has been applied, should correspond mostly to the differential receiver statics. The surface consistent statics model provides the theoretical framework. Adjacent Common Receiver Gathers (CRG) are crosscorrelated to obtain their time delay, namely their differential receiver statics. Stacking of PS-waves is not required, therefore the method does not depend on Vc (stacking velocity for converted wave), neither does it assume a simplified PS-wave stacking model. Application of receiver statics computed using this method on both synthetic and real data yielded encouraging results.