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others, 1985). Granitic intrusion accompanied the uplift and consequent erosion in
New England, and where magma broke through to the surface between Drake and
Armidale, a major eruptive region developed, generating terrestrial felsic volcanics
(including the Annalee Pyroclastics), and some marine volcanics on the northeastern
fringe. Actual vents have been identified and described (e.g. by McPhie, 1986). There
was also some andesitic activity in southeastern Queensland. The Gympie Terrane,
initially continuing with carbonate deposition, changed over to sandstone and shale
shelf clastic sedimentation.
The Bowen Basin remained marine at first, with continuing transgression in the west
and onto the Springsure Shelf leading into the southern Galilee Basin. Dropstones,
rafted in by seasonal ice (Draper, 1983), are abundant at some levels. Late in the
interval a coal-prone deltaic facies prograded from the north (Moranbah and German
Creek formations), to be interrupted by the same eustatic highstand responsible for
the Dempsey Formation in the Sydney Basin. The small Moorlands Basin, between
the Galilee and Bowen Basins north of Clermont, experienced three marine episodes
interspersed with paralic and fluvial interludes, including peatland development (Sorby
& Scott, 1988).
Extensive fluvial coal measures deposition resumed in the Galilee Basin, and later in
the Cooper Basin, to enlarge these basins to their greatest ever areal extent. Outflow
from both basins was into the Bowen Basin sea via the Springsure Shelf embayment.
The Galilee Basin was bordered by highlands of moderate relief, with some uplift in the
east (Hawkins, 1978). In the Cooper Basin, subsidence was greatest at the
southeastern end, and especially in the troughs, while the adjacent anticlinal ridges,
such as the Gidgealpa-Merrimelia-Innamincka culminations, stood above the
depositional plain. Some lakes were present within the peatlands.
Rifting in two places on the site of the later Laura Basin on Cape York Peninsula,
attended by some rhyolitic volcanism, allowed entry of the sea in places and the
initiation of paralic and fluvial facies, some with impure coal seams (de Keyser &
Lucas, 1968). The small Mount Mulligan and Olive River Basins preserved wholly
terrestrial coal measures sequences, in the former because of contemporaneous
faulting. North from Olive River there is no indication whether land or sea was present.
In the Bonaparte Basin, an early marine shelf setting was succeeded by the
construction of the delta and lagoon complex of the Cape Hay Member of the Hyland
Bay Formation (Bhatia & others, 1984; Mory, 1988). This enormous delta was more
than twice the size of that of the Mississippi. Similarly, the eastern Fitzroy Trough
received large volumes of deltaic and fluvial fill (Condren Sandstone), while the western
portion stayed marine. Late in the interval (lower Hardman Formation), the sea briefly
re-invaded the site, until displaced by barrier bar and accompanying lagoonal fades
encroaching over the area.
The remainder of the continent saw little change from its condition in Permian 5 time.
Some marine advancement continued in the Carnarvon Basin, to be reversed in the
later half of the time span causing the region to become emergent. Three regressiontransgression
cycles have been recognized in Tasmania, each transgression exposing
successively smaller areas in the southeast of the state to open marine levels of
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