OFR 151.pdf - CRC LEME

frequent only in occasional samples. Maastrichtian microfloras in Borda-1 are dominated by
Proteaceae, podocarps and ferns (Cyatheaceae, Gleicheniaceae), with lesser abundances of
Sphagnum. The combined data indicate that Austral Conifer Forest expanded at the expense
of Nothofagus communities during the Late Campanian-Maastrichtian, whilst coastal
communities continued to be dominated by mixed angiosperm-fern heath.
Inferred climate
Trends in the relative abundance of Nothofagus are likely to reflect drier (humid) conditions
during summer months (cf. Alley and Clarke 1992) and probably cooler (upper microtherm)
temperatures during winter given the persistent presence of Sphagnum, the absence of palms,
and the high latitude position of the basin (~70 0 S). Cooler ocean currents flowing into the
Australo-Antarctic Seaway are one explanation.
6.2.6 South-East Australia
1. Northern Tablelands
Undocumented samples submitted to the New South Wales Department of Mines indicate that
Maastrichtian coals outcrop somewhere near Kempsey on the Northern Tablelands,
northeastern New South Wales (McMinn 1986a). Neither the site, nor plant microfossils
recovered from the samples, can be relocated (A. McMinn pers. comm.).
Inferred climate
Unpublished notes (McMinn 1986a) only indicate the microflora included Gambierina. The
record is consistent with cool and probably humid climates. Whether these conditions reflect
topography or the mid latitude position (~60 o S) is unknown.
2. Otway Basin
Presence/absence data from Copa-1 (Macphail and Hos 1990) demonstrate Maastrichtian
(Manumiella druggii Zone) flora in the western Otway Basin included Dacrydium
(Lygistepollenites balmei), Gambierina, ancestral Nothofagus (Nothofagidites
brachyspinulosus, N. senectus), and a possible palm (Monosulcites gemmatus ms). These
data confirm climates were wet (humid-perhumid) and relatively cool (upper microtherm).
3. Gambier Basin
Rowett (1997b) has recorded a Cyatheaceae-Proteaceae dominated Forcipites longus Zone
Equivalent microflora in (onshore) McNicol-1 well. Rare taxa include Agathis/Wollemia,
Gambierina, Forcipites longus and Tricolporites lilliei.
4. Gippsland Basin
Detailed counts for the Sunfish-2, Tuna-1 and Tuna-4 wells (Tulip 1985, Tulip and Macphail
1986) indicate podocarps and Nothofagus populations were mostly replaced by floristically
complex communities dominated by Forcipites, Gambierina and Proteaceae. Many of the
latter produced large and/or highly ornamented pollen types that are likely to indicate insectpollination
(Macphail 1994a). Cryptogam values are more variable. For example
Cyatheaceae and Sphagnum are uncommon in Tuna-1 but remain frequent in Tuna-4.
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