Stratigraphic Aspects
Majors Creek Formation
Lennox et al. (2013) claim that we have arbitrarily changed the age of the Majors Creek Formation from Namurian (Roberts et al., 1995) to Visean. However, on page 38 we wrote that The Devonian-Carboniferous stratigraphy of the Hasting Block (Figure. 5) was based on Roberts et al. (1995), with the latest Carboniferous-early Permian stratigraphy from Schmidt, Aubourg, Lennox and Roberts (1994). This same stratigraphy is used in the current regional unpublished correlation charts of Roberts.
Tournasian and Visean zones in figure 3
We agree with Lennox et al. (2013) that there are some miscoloured chronostratigraphic horizons in figure 3 of Glen and Roberts (2012). In the caption to our figure 3 we wrote that "the Tournasian zones are over-emphasised in the Hastings Block, as are the Visean zones just north of Nelson Bay". This is simply a consequence of the problems of extracting key chronostratigraphic elements of figure 3 from the stratigraphic NSW state geology GIS database.
Offshore Uplift
Lennox et al. (2013) complain that no evidence has been provided to support the seismic interpretation of the Offshore Uplift of the cited authors. However, we pointed out in text and also in the caption to figure 9 (Glen and Roberts, 2012) that the shape of the aeromagnetic high northeast of the Newcastle Syncline (in figure 9a, and reproduced as a solid colour polygon in figure 1b, coincides with mapped arc volcanic rocks at Port Stephens (caption to figure 1b). On page 6 we wrote that "Petroleum exploration has identified undated (our emphasis) volcanic and volcaniclastic rocks that define the Offshore Uplift (Grybowski, 1992; Bradley, 1993; Alder et al., 1998; Bounty Oil and Gas NL, 2002; Breeze, 2009) (Figs. 1b) (see later). Breeze (2009) suggested these volcanic rocks are progressively overlain by Permian to Cenozoic strata, and aeromagnetic data indicate continuity and similarity with the Carboniferous arc (Nerong Volcanics) at Port Stephens (Fig. 1b)".
Curvature of early Permian units
Lennox et al. (point 2 shortcomings with figures, page 7, 2013) suggest that there are no Permian rocks near point G of Glen and Roberts (2012, figure 3). In fact, we did not indicate that there are Permian rocks at this locality. We used the letter G on figure 3 as a geographic marker when we said «Between E and G, the trends of these (Permian) outliers change from SSE to NNE, outlining a north-plunging synform in the east that overlies the forearc basin/subduction complex boundary». Between G and H (Fig. 3), shallow-water early Permian strata have been folded around the Hastings Block, separated from underlying Late Carboniferous strata by a disconformity or unconformity (Roberts et al., 1995).