OFR 151.pdf - CRC LEME

5. TIME SLICE T-5
Age Range: Late Miocene-Pliocene [11.2-1.78 Ma]
Zones: Monotocidites galeatus (Murray Basin)/Cingulatisporites bifurcatus
(Gippsland Basin) to Tubulifloridites pleistocenicus Zones. Informal
Oligospheridium Zones
5.1 Macrofloras
5.1.1 South-East Australia
1. Central Highlands of Victoria
Foliage of Callitris (Cupressaceae) is preserved in probable Plio-Pleistocene lacustrine clays
at Daylesford in the central highlands (K. Sneiderman pers. comm.).
Inferred climate
With the exception of C. macleayana, which occurs on rainforest margins, all Australian
Callitris are canopy species in open (dry sclerophyll) forests and woodlands (Boland et al.
1994). Most occur at lower elevations although one species, Callitris endlicheri, dominates
low open forest at higher elevations on the granite massif of Mt. Burrowa (1277 m) in
southeastern Victoria (Foreman and Walsh 1993). The Daylesford population may indicate
seasonally dry (possibly humid) and relatively warm (possible lower mesotherm) conditions.
5.1.2 Tasmania
1. West Coast
Phyllocladus stumps, which have been radiocarbon-dated as 26 ka, are preserved in situ occur
in a Late Pliocene palaeosol in the Linda Valley, western Tasmania (Macphail et al. 1993).
Inferred climate
Cool (microtherm) and wet (humid-perhumid) conditions are indicated.
5.2 Microfloras
Palaeobotanical evidence for Late Neogene climates in Australia up to 1991 are reviewed by
Kershaw et al. (1994) and Macphail (1997b). Climatic reconstructions are based on circular
reasoning to the extent that the inferred age of the assemblage is based on the presence or
absence of Tertiary rainforest species. The palaeoclimatic implications of a world class mid
Pliocene sequence at Yallalie in south-west Western Australia (Macphail 1994b) are
discussed in Dodson and Macphail (in press).
5.2.1 North-West Australia
1. North West Shelf
Turbidites, which have been deposited at depths of ~4000 m on the Argo abyssal plain,
preserve a highly generalised pollen record of the Late Miocene-Pleistocene vegetation
growing in the Kimberley region 600 km to the south (Martin and McMinn 1994). The Late
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