Starting in late 2010, seismic interpretation was undertaken on the PEP 381204 seismic data set by Kea Petroleum staff. This dataset consisted of 2D lines most of which had been reprocessed in 2008-2009. Kea's interpretation work focused mainly on the Eocene Mangahewa Formation and the Felix prospect. NZ Oil and Gas (NZOG) had drilled Opito-1 in 2001 and intersected sands of the Mangahewa Formation at the base of that well. Subsequent work by NZOG defined a structural closure up dip and north of Opito-1. Following the time interpretation of the seismic dataset, depth conversion was carried out using the Petrosys software package. Kea took a new approach to depth converting the Murihiku and sub-divided it. This work defined varying lithologies and allowed different interval velocities to be applied when depth conversion was carried out, resulting in a different interpretation than previous operators.