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northern New South Wales. The assemblage is dominated by monolete and trilete ferns and fern allies, associated with infrequent Casuarinaceae, Euphorbiaceae, Nothofagus and (one specimen) Tiliaceae. Inferred climate The source vegetation appears to have been fern-dominated wet scrub growing under uniformly wet (perhumid) and probably cool (lower mesotherm) conditions. Whether the cryptogam dominance reflects a recent wildfire (fire succession) or highly fertile soils (edaphic disclimax) is unknown. 2.2.3 Central Australia Tertiary basins in the Alice Springs district and Lake Eyre Basin (Eyre Formation) preserve thin carbonaceous units of probable Early Eocene age (age range latest Paleocene-late Early Eocene). Many of these preserve very diverse microfloras, some of which also include dinoflagellate species that are usually associated with saline conditions (Sluiter 1991, Macphail 1996c, 1997a, Alley 1998). The reason for this is unclear but salinity levels may have been raised due to discharge of saline groundwater, leaching of salt from outcrops of Early Cretaceous or older marine sediments, e.g. the Bitter Springs Formation, or deposition within hydrologically-closed basins. Microfloras from the Eyre Formation are similar to those recorded in the Late Paleocene and, apart from the absence of mangroves, are also similar to Early Eocene assemblages found in coastal northwestern Australia. 1. Alice Springs district Early Eocene microfloras from the Santa Teresa and Ti-tree Basins, Alice Springs district are dominated by Casuarinaceae, Proteaceae including large (mostly described) and many small (undescribed) types, and tricolporate types. These are associated with occasional high values of monolete spores, Acrostichum-type (Cyathidites splendens), Gleicheniaceae and other trilete fern spores, and Euphorbiaceae (Malvacipollis). Araucariaceae, Dacrydium, Lagarostrobos (Phyllocladidites reticulosaccatus), Cupanieae and a member of the otherwise wholly Northern Hemisphere Triprojectites group (Integricorpus) are frequent in some samples. Rare taxa include Pteris, Lygodium, Lagarostrobos, Palmae (Arecipites, Longapertites, Nupharipollis), Anacardiaceae (Striacolporites cf. cephalus), Anacolosa (Anacolosidites acutullus), Beauprea, Callitrichaceae, Gunnera, Ilex, Sapotaceae (Sapotaceoidaepollenites latizonatus) and Tiliaceae. Nothofagus is very rare and the records may be due to downhole contamination. 2. Lake Eyre Basin Microfloras dated as Paleocene in Lake Eyre Bore 8A drillhole (Alley 1983a) are more likely to be Early Eocene, based on Myrtaceidites tenuis and Proteacidites pachypolus, which first occur in the Gippsland Basin in the Lower Malvacipollis diversus Zone. The assemblages are dominated by small angiosperm pollen types (possibly Cunoniaceae, Elaeocarpaceae) associated with Gleicheniaceae, Cupressaceae, Podocarpaceae (Dacrydium, Lagarostrobos, Microcachrys, Podocarpus-Prumnopitys), Ascarina, Casuarinaceae, Euphorbiaceae, Myrtaceae, Nothofagus (Nothofagidites flemingii), and diverse Proteaceae. Pollen data from the Muloorina-2 and Poonarunna-1 wells (Sluiter 1991) hint that Myrtaceae, Proteaceae, a wholly extinct lineage of Lagarostrobos (Phyllocladidites reticulosaccatus) and Podocarpus-Prumnopitys expanded at the expense of Cunoniaceae, Cupressaceae- 217
Taxodiaceae and Araucariaceae during the Early Eocene. Cyatheaceae are rare relative to the underlying Late Paleocene microfloras. Inferred climate The high degree of variation between assemblages points to the source being a mosaic of ecologically disparate taxa whose affinities may lie anywhere from modern tropical (megatherm) to cool-cold temperate (microtherm) rainforest. The combined evidence, however, implies that conditions were very warm (upper mesotherm) and seasonally very wet (perhumid). Sluiter (1991) has interpreted ecological trends in the Lake Eyre Basin as indicating the complex angiosperm rainforest types evolved in response to an increase in the mean annual rainfall and temperature (to ~22 0 C). 2.2.4 South-West Australia 1. Carnarvon Basin Basal Early to basal Middle Eocene sediments at 1135-1257 m in Alpha North-1 preserve diverse microfloras, which are dominated by Casuarinaceae (Haloragacidites harrisii), and unidentified tricolporate types and include frequent to common Euphorbiaceae (Malvacipollis diversus) and Proteaceae (M.K. Macphail unpubl. data). The gymnosperm flora is more diverse than in Jacaranda-1 (Bonaparte Basin). Gymnosperms (Araucaria, Cupressaceae, Dacrydium, Podocarpus-Prumnopitys, Agathis/Wollemia) are much more common and Myrtaceae, Cupanieae, Nypa and Restionaceae (Milfordia homeopunctata) less common than in the Bonaparte Basin. Rare taxa include Lycopodiaceae, Selaginella, Acrostichum-type (Cyathidites splendens), Gleicheniaceae, Lygodium, Pteris, Sphagnum, Anacardiaceae (Ailanthipites, Striacolporites cf. cephalus) Anacolosa (Anacolosidites acutullus), Banksia (Banksieaeidites elongatus), Convolvulaceae (Perfotricolpites), a possible Eucalyptus (Myrtaceidites tenuis), Euphorbiaceae (Malvacipollis spp.), Gunnera, Ilex, Musgraveinae (Banksieaeidites arcuatus), Nothofagus (Brassospora, Fuscospora), Nypa, Poaceae, Polygalaceae (Polycolporopollenites esobalteus), Santalum (Santalumidites cainozoicus) and Stylidiaceae (Tricolpites stylidioides). Inferred climate The paucity of megatherm taxa such as Nypa, the relatively prominent representation of gymnosperms and cryptogams, and the presence of Nothofagus indicates that mean air temperatures within the Carnarvon Basin were slightly cooler (upper mesotherm) than in the Bonaparte Basin (possibly megatherm). Rainfall may have been similar, i.e. very wet (perhumid), with a (pronounced) dry season. The apparent poor development of coastal swamps may be due to local tidal regimes rather than the regional rainfall. 2. Perth Basin Abundant angiosperm pollen, including Proteaceae, is reported to occur in dinoflagellatedominated assemblages from the Kings Park Shale interval intersected in the Sir James Mitchell Park-2A bore, Perth (Backhouse 1981). The age of this microflora is uncertain (possible Early Eocene) but Churchill (1973) and Jarzen and Pocknall (1993) have reported Nypa and Strasburgeriaceae (Bluffopollis scabratus) pollen, respectively, from the same formation. Inferred climate Assuming that the record of Nypa is correct, then conditions within the southern Perth Basin (palaeolatitude ~60 0 S) were very warm to hot (upper mesotherm) and seasonally very wet (perhumid). 218
Page 1 and 2:
CRCLEME Cooperative Research Centre
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Electronic copies of the publicatio
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and, for Tertiary continental seque
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2. Analysis of a Plio-Pleistocene l
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Table A (cont.) Basin and related s
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Figure A: Generalised climatic curv
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Carpenter, R.J., Hill, R.S., Greenw
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Hill, S.M., Eggleton, R.A. and Tayl
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Macphail, M.K. and Stone, M.S., 200
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Swenson, U., Backlund, McLoughlin,
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EXECUTIVE SUMMARY This review prese
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Temperature Climates in palaeo-sout
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SUMMARY OF INFERRED CRETACEOUS PALA
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INTRODUCTION Mineral resources, whe
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Professor B. Balme (Geology Departm
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Section 7 (Tertiary climates) This
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vegetation. Moreover, individual ta
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1.3 Flora, vegetation and climate 1
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TABLE 2: Classification of vegetati
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Figure 2: Relationship of different
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Accordingly, only at sites with exc
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2.1.3 Palaeoecology Palaeoecology i
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wind-pollinated trees and shrubs bu
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1. The usual practice of equating t
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1. Palaeontological evidence Like p
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5. Facies architecture and lithostr
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Subsequent developments include mel
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SECTION 4 (GEOGRAPHIC BOUNDARIES AN
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SECTION 5 (EARLY CRETACEOUS CLIMATE
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events on other continents and sugg
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If these considerations apply to th
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surrounding basins. Thick sands ero
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Haig and Lynch 1993, Erbacher et al
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SECTION 6 (LATE CRETACEOUS CLIMATES
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has highlighted the roles played by
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6.4.2 Palaeobotany Cenomanian flora
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Palaeo-southern Australia Dryland c
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6.7 Time Slice K-6. Late Campanian-
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7.1. Global backdrop SECTION 7 (TER
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Explanations for the PETM are centr
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East Antarctica and strengthening o
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amplifying, pacing and potentially
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southeastern Australia than elsewhe
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7.4 Time Slice T-1. Paleocene [65-5
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Palaeo-southern Australia Unlike no
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Palaeo-central Australia As for the
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7.6.2 Palaeobotany The palaeobotani
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Zone microfloras imply temporary wa
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in the Bass Basin, the basal Seaspr
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Similarly it is difficult to summar
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However, the data are emphatic that
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margin of plateau were cooler (~7 0
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fossil taxa that are morphologicall
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during Late Pleistocene glacial max
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SECTION 8 (CONCLUSIONS) Climatic in
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• On present indications, Early C
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TABLE 8a: INFERRED CRETACEOUS PALAE
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8.2 Results in prospect (recommenda
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The 10 μm sieved, oxidised extract
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phenology. The method also provides
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SECTION 9 (REFERENCES) Acton, G.D.
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Ashley, P.M., Duncan, R.A. and Feeb
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Birks, H.J.B. and Gordon, A.D., 198
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Burnham, R.J., 1989. Relationships
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Clarke, J.D.A., 1994. Evolution of
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Dettmann, M.E. and Playford, G., 19
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Evans, P.R., 1970b. Palynology of H
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Godthelp, H., Archer, M., Cifelli,
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Harris, W.K., 1974. Biostratigraphy
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Hill, R.S., 1994b. Nothofagus smith
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Holland, S.M. and Patzkowsky, M.E.,
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Australia: paleoceanographic implic
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Lindsay, J.M. and Harris, W.K., 196
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Macphail, M.K., Colhoun, E.A. and F
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McGowran, B. and Beecroft, A., 1985
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Morgan, R., 1977. Palynology of Ter
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Abstracts of the Annual General Mee
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Raymo, M.E., Grant, B., Horowitz, M
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Sereno, P.C., 1999. The evolution o
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Taylor, G., 1998. Prediction of mod
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Webb, L.G., 1968. Environmental rel
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Zachos, J.C., Stott, L.D. and Lohma
Page 168 and 169: APPENDIX 1 CRETACEOUS DATA 167
Page 170 and 171: 1. TIME SLICE K-1 Age Range: Berria
Page 172 and 173: Australian assemblages, located on
Page 174 and 175: 2. Officer Basin Dinoflagellates in
Page 176 and 177: 2. TIME SLICE K-2 Age Range: Aptian
Page 178 and 179: Inferred climate The combined data
Page 180 and 181: Dettmann et al. (1992) have argued
Page 182 and 183: 3. TIME SLICE K-3 Age Range: Cenoma
Page 184 and 185: 3.2.2 North-East Australia 1. Carpe
Page 186 and 187: 4. TIME SLICE K-4 Age Range: Turoni
Page 188 and 189: 1. Otway Basin Limited data (Macpha
Page 190 and 191: 5. TIME SLICE K-5 Age Range: Early
Page 192 and 193: Inferred climate The data indicate
Page 194 and 195: 6. TIME SLICE K-6 Age Range: Late C
Page 196 and 197: Contrary to global cooling trends d
Page 198 and 199: Inferred climate The relatively goo
Page 200 and 201: Inferred climate As for regions to
Page 202 and 203: APPENDIX 2 TERTIARY DATA 201
Page 204 and 205: 1. TIME SLICE T-1 Age Range: Paleoc
Page 206 and 207: also include relatively frequent No
Page 208 and 209: Inferred climate Some differences b
Page 210 and 211: Microfloras preserved in the Lower
Page 212 and 213: subtropical affinities are rare, hi
Page 214 and 215: 2. TIME SLICE T-2 Age Range: Early
Page 216 and 217: Inferred climate Climates appear to
Page 220 and 221: 2.2.5 Central southern Australia Ha
Page 222 and 223: a number of distinctive Proteaceae
Page 224 and 225: Inferred climate The Regatta Point
Page 226 and 227: 3. TIME SLICE T-3 Age Range: Middle
Page 228 and 229: 2. Lake Torrens Basin Abundant leaf
Page 230 and 231: Dominance is highly variable. For e
Page 232 and 233: types (M.K. Macphail unpubl. data).
Page 234 and 235: Dacrycarpus), Euphorbiaceae (Austro
Page 236 and 237: (possibly upper mesotherm) and drie
Page 238 and 239: Basin) on the Eyre Peninsula (Alley
Page 240 and 241: explanation is that a warm water gy
Page 242 and 243: several taxa, which first appear in
Page 244 and 245: 4. TIME SLICE T-4 Age Range: Oligoc
Page 246 and 247: Inferred climate The southern limit
Page 248 and 249: The lowest and possibly the oldest
Page 250 and 251: Dominants include fresh to brackish
Page 252 and 253: Based on the relative abundance of
Page 254 and 255: (Morgan 1977, McMinn 1981a, Martin
Page 256 and 257: common (up to 5-6%) in the middle s
Page 258 and 259: Polypodiaceae, Palmae (Dicolpopolli
Page 260 and 261: Strasburgeriaceae. Proprietary info
Page 262 and 263: Rare taxa which first appear in the
Page 264 and 265: Correlative microfloras in the onsh
Page 266 and 267: impression of floristic impoverishm
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(Lophosoria) reached Tasmania befor
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2. Otway Basin Oxygen isotope strat
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5. TIME SLICE T-5 Age Range: Late M
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Casuarinaceae, Cunoniaceae, Elaeoca
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maximum temperature of the hottest
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Nothofagus-gymnosperm temperate rai
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5.2.7 Tasmania Late Neogene sedimen
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