OFR 151.pdf - CRC LEME

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Nothofagus-gymnosperm temperate rainforest within (Late Miocene, Late Pliocene) predominantly wet sclerophyll forest types. Inferred climate The expansion of Nothofagus (Lophozonia) spp. is likely to be due to uniformly wet (perhumid) and cool (upper microtherm) conditions on the upper slopes of the Southern Highlands during an interval (Early Pliocene) when other sites in southern Australia experienced increasing warmth. The most plausible explanation is that warm sea surface temperatures and high relative sea levels resulted in increased orographic cloudiness, and therefore effectively cooler wetter conditions, over the Southeastern Highlands. 3. Otway Basin Grange Burn, at 180 m elevation, near Hamilton in south-western Victoria is located close to the limits of marine transgression in the Otway Basin during Late Neogene time. The site provides a record of an Early Pliocene environment that is unique in Australia for two reasons. A regressive non-marine alluvium is preserved between a late Miocene-Early Pliocene marine silt and a K/AR-dated 4.46 Ma old basalt. Fossils preserved in the alluvium include the remains of plants and mammals animals whose NLRs are confined to coastal northeastern Queensland (Flannery et al. 1992, Macphail 1996b). Commonly occurring microfossils include Cyathea, Araucariaceae (Araucaria), Podocarpaceae (Dacrycarpus, Podocarpus-Prumnopitys), Casuarinaceae and Myrtaceae (including Eucalyptus). Less common or rare taxa are Dacrydium, Asteraceae, Eucalyptus spathulata-type, Nothofagus (Brassospora, Fuscospora, Lophozonia) spp. and Poaceae. Inferred climate The combined microfloral and palaeontological evidence point to a mosaic vegetation of Araucariaceae (dry) rainforest and open-canopy sclerophyll communities, which may have been confined to the stream banks. There is no evidence that Nothofagus spp. were part of these communities or present elsewhere in the district. Poaceae are suggested to have colonised drier (interfluve) areas but there is no evidence that grasslands per se were part of the regional dryland vegetation. Macphail (1996b) has proposed that climates were wet (humid) and weakly seasonal. Mean annual temperatures are likely to have been very warm (upper mesotherm). 4. Murray Basin Marine transgressions during the Late Miocene and Early Pliocene resulted in the deposition of marginal marine facies in the south-west sector of the basin. Examples are the Bookpurnong Beds and basal Loxton-Parilla sands (Brown and Stephenson 1991). Microfloras from restricted marine and estuarine facies are dominated by Araucariaceae, Casuarinaceae and/or Myrtaceae, with relatively low and diminishing relative abundances of Nothofagus (Brassospora) spp. Microfloras from paralic facies where the marine influence was weak or absent are dominated by Nothofagus (Brassospora), Araucariaceae and Casuarinaceae, with lower abundances of Myrtaceae. These facies are difficult to correlate using plant microfossils and it is uncertain whether differences in pollen dominance are due to the Neves Effect, edaphic-forcing or evidence that Nothofagus-dominated rainforest was succeeded by drier, Araucariaceae-dominated, types of rainforest. 277
Inferred climate If the data merely reflect spatially heterogeneous rainforest communities, then climates in the central west Murray Basin were warm (mesotherm range) and wet to very wet (perhumid) during the Early Pliocene. Conversely if the data represent successional trends within the rainforest vegetation, then climates became increasing seasonal (effectively drier) and possibly warmer (upper mesotherm) during the same period. 5. Central Highlands of Victoria A probable Plio-Pleistocene sequence is preserved in a volcanic crater (Stony Creek Basin) at Daylesford in central highlands. Preliminary data (M.K. Macphail pers. observation, based on material supplied by K. Sneiderman) indicate plant communities surrounding the crater lake were a mosaic of sclerophyll and temperate rainforest taxa. The latter included taxa that were last recorded in the Gippsland Basin during the Late Miocene or Early Pliocene, e.g. Lophosoria, Dacrycarpus, Dacrydium, an extinct relative of Microcachrys (Podosporites microsaccatus), Nothofagus (Brassospora) spp. and Symplocos, rainforest taxa with subtropical to tropical NLRs that are typical of mid Pliocene sites in southern Australia, e.g. Araucaria and Agathis/Wollemia, and sclerophyll shrubs that are not part of the present-day vegetation in central Victoria, e.g. Stirlingia. Inferred climate The Stony Creek Basin appears to have been a refuge for Tertiary rainforest taxa, possibly due to highly fertile basaltic soils mitigating the effects of any wildfires (Jackson 1968). Conditions are likely to have been relatively warm (mesotherm range) and wetter than at present but by how much is unclear (see Section 5.1.1). 6. Gippsland Basin Microfloras recovered from deepwater carbonates (Seaspray Group) in Hapuku-1 provide a quasi-continuous record of plant communities occupying the Gippsland coastal plain throughout the Neogene. Relative abundance values reflect a strong Neves Effect due to the offshore/deepwater location of the well. Key events (Macphail 1997b) are: (1) the expansion of Araucaria and Podocarpus- Prumnopitys at the expense of Nothofagus (Brassospora) spp. during the latest early Miocene; (2) a marked increase in Cyathea, associated with a decrease in rainforest gymnosperms to low (
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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
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APPENDIX 1 CRETACEOUS DATA 167
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1. TIME SLICE K-1 Age Range: Berria
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Australian assemblages, located on
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2. Officer Basin Dinoflagellates in
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2. TIME SLICE K-2 Age Range: Aptian
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Inferred climate The combined data
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Dettmann et al. (1992) have argued
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3. TIME SLICE K-3 Age Range: Cenoma
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3.2.2 North-East Australia 1. Carpe
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4. TIME SLICE K-4 Age Range: Turoni
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1. Otway Basin Limited data (Macpha
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5. TIME SLICE K-5 Age Range: Early
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Inferred climate The data indicate
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6. TIME SLICE K-6 Age Range: Late C
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Contrary to global cooling trends d
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Inferred climate The relatively goo
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Inferred climate As for regions to
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APPENDIX 2 TERTIARY DATA 201
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1. TIME SLICE T-1 Age Range: Paleoc
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also include relatively frequent No
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Inferred climate Some differences b
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Microfloras preserved in the Lower
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subtropical affinities are rare, hi
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2. TIME SLICE T-2 Age Range: Early
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Inferred climate Climates appear to
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northern New South Wales. The assem
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2.2.5 Central southern Australia Ha
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a number of distinctive Proteaceae
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Inferred climate The Regatta Point
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3. TIME SLICE T-3 Age Range: Middle
Page 228 and 229: 2. Lake Torrens Basin Abundant leaf
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Page 234 and 235: Dacrycarpus), Euphorbiaceae (Austro
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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
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Page 250 and 251: Dominants include fresh to brackish
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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
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Page 270 and 271: 2. Otway Basin Oxygen isotope strat
Page 272 and 273: 5. TIME SLICE T-5 Age Range: Late M
Page 274 and 275: Casuarinaceae, Cunoniaceae, Elaeoca
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Page 280: 5.2.7 Tasmania Late Neogene sedimen
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