Sequence-stratigraphic interpretations of outcrop, drillcore, wireline and seismic datasets are integrated with SHRIMP zircon and palaeomagnetic determinations to provide a detailed chronostratigraphic basin framework for the base-metal-rich Palaeoproterozoic rocks of the southern McArthur, Lawn Hill and Mt Isa regions. The analysis forms a basis for future correlations across northern Australia. Nine second-order unconformity-bounded supersequences are identified. Supersequences have a duration of 10-20 million years; some hitherto-unrecognised unconformity surfaces record up to 25 million years of missing rock record. The second-order supersequences contain a series of nested third-, fourth-and fifth-order sequences many of which can be correlated across the Mt Isa, Lawn Hill and southern McArthur regions. The analysis relates accommodation history to major intraplate tectonic events evident on the apparent polar wander path for northern Australia. Major tectonic events at approximately 1735 Ma, and 1575 Ma impacted on accommodation rates and basin shape in northern Australia. Sub-basin depocentres, the hosts for major sulfide mineralisation, are attributed to reactivated faults that controlled local subsidence. Pb/Pb model ages of 1653 Ma, 1640 Ma and 1575 Ma for the Mt Isa, McArthur River and Century Pb-Zn-Ag deposits, suggest that changes to intraplate stresses at tectonic events of like age resulted in the migration of metal-bearing fluids into the sub-basins. A Pb/Pb model age of 1675 for the Broken Hill deposit suggests that intraplate stresses manifest in northern Australia also affected rocks of similar age further south. Magmatic events close to 1700 Ma (Weberra Granite) and 1675 Ma (Sybella Granite) coincide with times of regional incision and the formation of supersequence-bounding unconformity surfaces.

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The Mount Isa Basin is a new concept to describe the area of Palaeo- to Mesoproterozoic rocks south of the Murphy Inlier (not the Murphy Tectonic Ridge) and inappropriately described as the Mount Isa Inlier. The new basin concept presented in this paper allows the characterisation of basin-wide structural deformation and the recognition of areas with petroleum exploration potential.The northern depositional margin of the Mount Isa Basin is the metamorphic, intrusive and volcanic complex referred to as the Murphy Inlier. The eastern, southern and western boundaries of the basin are obscured by younger basins (Carpentaria, Eromanga and Georgina Basins). The Murphy Inlier rocks comprise the seismic basement to the Mount Isa Basin sequence. Evidence for the continuity of the Mount Isa Basin with the McArthur Basin to the northwest and the Willyama Block (Basin) at Broken Hill to the south is presented. These areas combined with several other areas of similar age are believed to have comprised the Carpentarian Superbasin.The application of seismic exploration within Authority to Prospect (ATP) 423P at the northern margin of the basin was critical to the recognition and definition of the Mount Isa Basin. The northern Mount Isa Basin is structurally analogous to the Palaeozoic Arkoma Basin of Oklahoma and Arkansas in the southern USA but as with all basins it contains unique characteristics, a function of its individual development history. The northern Mount Isa Basin is defined as the basin area northwest of the Mount Gordon Fault.

This essay argues that theatre and performance scholars should use theories that can be scientifically validated whenever possible. Scientists cannot arrive at objective knowledge, but through the process of falsification they can narrow their range of possible interpretations to provide explanations that best suit the evidence and counter the arguments of others. The cognitive sciences are now providing falsifiable explanations for many theatre and performance phenomena, such as attention, empathy, and conceptualization. In contrast, many of the theories current in our discipline, including those reliant on psychoanalysis and poststructuralism, are not open to the protocols of good science. On the basis of falsifiablity, the essay demonstrates the superiority of two theories from cognitive science over approaches current in our discipline with regard to the problem of how spectators understand theatrical doubleness and action on the stage. It also suggests that a-scientific theories can be useful for scholarship when they are in accord with good science and allow us to extend the range of our discussions and conclusions.

Sequence‐stratigraphic interpretations of the 4200 m‐thick Palaeoproterozoic (1700–1650 Ma) Mt Isa Group and underlying Surprise Creek Formation identify three unconformity‐bounded packages termed the Prize, Gun and Loretta Supersequences. Siliciclastic rocks of the Surprise Creek Formation and Warrina Park Quartzite comprise the Prize Supersequence. Rapid facies changes from proximal, conglomeratic fluvial packages to distal, fine‐grained and deep‐water, rhythmites characterise this supersequence. Conglomeratic intervals in the Mt Isa area reflect syndepositional movement along basin‐margin faults during the period of supersequence initiation. A major unconformity, which extends over a period of about 25 million years, separates the Gun and Prize Supersequences. In the Leichhardt River Fault Trough uplift and incision of Prize sedimentary rocks coincided with emplacement of the Sybella Granite (1671 ± 8 Ma) and Carters Bore Rhyolite (1678 ± 2 Ma) and the removal of an unknown thickness of Prize Supersequence section. Deep‐water, turbiditic rhythmites of the Mt Isa Group dominated the Gun and Loretta Supersequences. Tempestites are present over discrete intervals and represent times of relative shallowing. High accommodation and sedimentation rates at the base of the Gun Supersequence resulted in the deposition of transgressive nearshore facies (uppermost Warrina Park Quartzite) overlain by a thick interval of deep‐water, siltstone–mudstone rhythmites of the Moondarra Siltstone and Breakaway Shale. With declining rates of siliciclastic sedimentation and shallowing of the succession, calcareous sediments of the Native Bee Siltstone prograded over the deeper water deposits. Two third‐order sequences, Gun 1 and 2, characterise these lower parts of the Gun Supersequence. An increase in accommodation rates near the top of the Native Bee Siltstone in Gun 3 time, resulted in a return to deep‐water sedimentation with deposition of dolomitic rhythmites of the Urquhart Shale and Spear Siltstone. The Pb–Zn–Ag ore‐ hosting interval of the Urquhart Shale is interpreted to occur in progradational highstand deposits of the Gun 3 Sequence. In the Leichhardt River Fault Trough the Loretta Supersequence boundary forms a correlative conformity. Coarser grained and thicker bedded sediments of the Kennedy Siltstone comprise lowstand deposits at the base of this cycle. These sediments fine up into the transgressive, deep‐water, siliciclastic facies of the Magazine Shale, which in turn are truncated against the Mt Isa Fault.