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elatively few.
As noted earlier, it was impractical at the time of compilation to present the maps on
a palinspastic base. For the New England Orogen, it is known that the Gynnpie
Terrane lay at an unspecified distance to the east of its present position, and docked
with eastern Australia during the mid-Triassic (Harrington, 1983). The Curtis Terrane
may have docked during the mid-Permian (Brakel & Totterdell, 1988). Strike-slip
movements of about 500 km have been postulated along the Mooki Fault system
(Harrington & Korsch, 1985b), and the Texas - Gaffs Harbour Megafold may have
formed as late as the Early Permian (Murray & others, 1987). As a result, the
palmogeography mapped for the orogen may bear little relationship to the distribution
of the rock units at the time of their formation. This tectonically naïve presentation is
preferable to leaving the orogen blank, because at least the palmo-environments of
the present outcrop areas are depicted. The exotic derivation of the Gympie and
Curtis Terranes is indicated on the maps by white line boundaries, but there may be
others not yet recognised. Flood & Aitchison (1988) defined 11 terranes in New
England, and some of these may not have been in their present positions in the
Permian. Research on the tectonic evolution of the New England Orogen is currently
being pursued vigorously on several fronts, and a reasonable palinspastic
reconstruction of this region will have to await the outcome of this work.
During the Permian, Australia was a part of eastern Gondwanaland (Fig. 5). The
present Lord Howe Rise and New Zealand lay to the east and southeast of Australia,
while Antarctica adjoined its southern margin (Lawyer & Scotese, 1987). To the west,
a land mass often referred to as "Greater India" was present, the part abutting
southwestern Australia probably being modern Assam. Palinspastic reconstruction of
the Himalayan fold belt (Klootwijk & others, 1985) suggests that this land mass
extended north along the Western Australian coast as far as North West Cape (Powell
& others, 1988). Farther along the northwestern and northern margins of the
Australian plate, reconstructions of former neighbouring continental blocks are more
nebulous. Most workers believe that blocks now incorporated into Asia were part of
this region of Gondwana. Palmomagnetic work on the Chinese blocks shows that
these were already moving across central Tethys by the Late Carboniferous (Lin,
1987), and were far from Australia during the Permian (McElhinny & others, 1981;
McFadden & others, 1988). A recent reconstruction by Audley-Charles (1988)
proposes that South Tibet lay opposite North West Cape, and Burma along the
Northwest Shelf, with a line of other blocks such as North Tibet and Indochina still
farther to the northwest; Thailand, Malaya, and various Indonesian fragments were
arrayed along the margin west and north of New Guinea. North Tibet - Indochina was
rifted off in the Late Permian, but the other blocks remained attached to Australia until
the Late Jurassic. Metcalfe (1988), however, argues that the latter blocks (Sibumasu)
had already been rifted from Gondwana by latest Early Permian times.
In the remainder of this section, each of the seven time slices will be dealt with in turn,
starting with the oldest. As the tectonics has already been treated under a separate
heading, the sedinnentological aspects of the palmogeography will be emphasised
here, although the two topics are of course inextricably associated. No attempt is
made to detail the entire Permian geology of Australia, or to cite every source of data,
because just listing every reference that has ever been published on the Permian
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