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Because of these differences, we chose two viable conceptual models for the SW Hub. The first conceptualmodel for the SW Hub project (Figure 2.9) is based on a structural interpretation of the northern-mostEast-West seismic line (GA2011-LL1) across the Harvey Ridge. Of the new seismic data, this line hasthe best S/N ratio when compared to the existing seismic lines, a greater amount of geological structureand intersects a likely (Barclay et al., 2009) injection site at about 10 km horizontal distance. Thisconceptual model will be used in Sections 4.1.3 and 4.1.4 of this report.A0Westhorizontal distance (km)East0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16B−1elevation (km)−2−3Tertiary sedimentsJurassic sedimentsMyallupWonnerupSabina sandstones & Sue group1D model location−4Figure 2.9: South West Hub Project conceptual model 1. This model was derived from line GA2011-LL1, the northern most seismic line AB in Figure 2.2. This report takes the region around10 km as the most likely injection site. Seismic data from GA2011-LL1 were shown inFigure 2.8(a).The second conceptual model is illustrated in Figure 2.10. From Figure 2.6, this is most central of theWest-East 2011-vintage seismic lines and it intersects the Harvey-1 well. The veracity and applicabilityof this model should be proven once data from this well are available. This conceptual model will beused in Sections 4.1.4 and 4.1.6.1 of this report. Since these sections deal with 2D surface and boreholeseismic monitoring, we choose to include more structure in the model by including interpreted subdivisionof Jurassic into Eneabba, Cattamarra, and Cadda formations, and adding Cretaceous sediments(Wanbro).To construct the model, the interpreted horizons were converted from time to depth using interval velocitiesobtained from the migration velocities. The corresponding interval velocities are summarisedin Table 2.1. The P-wave velocities are well correlated with log data from Lake Preston 1 well. Thedensities of the interval were obtained using Gardner’s empirical relation Gardner et al. (1974). Sincewe do not have direct measurements of S- wave velocities, these were derived using Castagna’s equation(mudrock line).| 21