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Intercontinental Correlation by Conchostracans and Palynomorphs from Antarctica, Western Australia, India, and Africa Palynomorp

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Intercontinental Correlation by Conchostracans and Palynomorphs from Antarctica, Western Australia, India, and Africa Palynomorp References genera nonmarine dispersal routes between Africa, India and western Australia can account for the distribution. Cosmopolitan distribution of Mesozoic conchostracan genera in the southern continents including Antarctica is at- Runnegar, B., and J Pojeta, Jr. 1974. Molluscan phylogeny: the . tributed to continental ligature or proximity. By contrast paleontological viewpoint. Science, 186: 311-317. the conchostracan speciation program was restricted to local Unusual Upper Cambrian fauna from West Webers, G.F. 1972. in Antarctica. Antarctic Geology and Geophysics. Universitet- or regional situations (isolated lakes or ponds) (Tasch, forlaget, Oslo, 235-237. press). Yochelson, EL., R.H. Flower, and G.F. Webers. 1973. The bear- This research was supported by National Science Founda- ing of the new Late Cambrian monoplacophoran genus tion grant OPP 73-05831. Knightoconus upon the origin of the Cephalopoda. Lethaza, 6: 275-310. References Tasch, P. In press. Crustacean branchiopod distribution and specia- Intercontinental correlation by tion in Mesozoic lakes of the southern continents. In: Antarctic Research Series (B.C. Parker, ed.). conchostracans and Tasch, P., and P.M. Oesterlen. 1977. New data on the "Phyllopod Beds" (Karroo System) Northern Angola. South Central palynomorphs from Antarctica, Geological Society America, Annual Meeting (El Paso). Abstracts western Australia, India, and with program: 77. Africa PAUL TASCH Palynomorph preservation in the Department of Geology Wichita State University Beacon Supergroup of the Wichita, Kansas 67208 Transantarctic Mountains All three Tasch stations at Carapace Nunatak were found ROSEMARY A. KYLE to have the components of Balmes Exesipollenites Assemblage from the Perth and Carnarvon Basins of Institute of Polar Studies western Australia (Jurassic, probably late Liassic). Excellent palynomorphs were recently recovered from a few Storm JAMES M. SCHOPF Peak samples (lower interbed, Tasch stations 0 and 1). Residues were good to massive. This contrasts with the Institute of Polar Studies and general situation of palynomorph- barren beds in both lower Department of Geology, and upper interbeds at Storm Peak, These new data will be The Ohio State University reported by P. Tasch and J.M. Lammons at the Interna- Columbus, Ohio 43210 tional Palynological Colloquium, Leon, Spain in September 1977. A paper with T.J. Jones on the "Conchostracan fauna of Flat-lying sedimentary rocks of the Early Devonian to Ear- the Carboniferous and Triassic of the Canning Basin" is be- lyjurassic Beacon Supergroup occur throughout the Trans- ing readied for publication by the Bureau of Mineral antarctic Mountains. Several workers (e.g. Schopf, 1962; Resources (CS I RO, Canberra, Australia). Besides descrip- Norris, 1965; Helby and McElroy, 1969; Kemp, 1972; Kyle, tion of the fauna, findings suggest a post-Carboniferous in press) have experienced difficulty in extracting dispersal of ribbed conchostracan eggs from Canning Basin recognizable palynomorphs from Beacon rocks. The poor of western Australia to the Bowen Basin and the Newcastle preservation or absence of palynomorphs is attributed to Coal Measures belt in eastern Australia. Permian ribbed thermal metamorphism during the intrusion of the Jurassic conchostracans from the Ohio Range, have long since been Ferrar Group dolerite sills and extrusion of the comagmatic shown to correlate with equivalents in the Newcastle Coal Kirkpatrick Basalt. This igneous activity has also resulted in Measures. the carbonization of plant cuticles and woody material, the Correlation of nonmarine deposits of the Karroo System semi-anthracite rank of the Permian and Triassic coal, and "Phyllopod Beds" (Northern Angola) and those of the the formation of zeolites typical of low grade metamor- Triassic Panchet Formation (Raniganj Basin, India) has phism. been strengthened by discovery of three conchostracan Over 500 samples from the Beacon Supergroup of the genera common to both formations: Estheriina, Cornia, Transantarctic Mountains have been processed for Paleolimnadia (Tasch and Oesterlen, 1977). Since the palynological study. In some areas (e.g., southern Victoria Triassic of the Canning Basin has species of two of these Land and the Nilsen Plateau, Queen Maud Mountains) only October 1977 121 25 percent of the samples processed have yielded palyno- Schopf, J.M. 1962. A preliminary report on plant remains and coal morphs, and 25 percent of these assemblages contain of the sedimentary section in the central range of the Horlick palynomorphs so rare or so poorly preserved that no worth- Mountains, Antarctica. Institute of Polar Studies, Ohio State while information can be gained from them. The yield in University, Report 2. 61p. the Ohio Range was somewhat higher; about 50 percent of Schopf, J.M., and W.E. Long. 1966. Coal metamorphism and ig- the processed samples contained palynomorphs, but neous associations in Antarctica. In: Coal Science (Gould, R.F., relatively few of these can be assigned with any certainty to ed.), American Chemical Society Advances in Chemistry Series, species level. The lithologies of productive samples include 55: 156-195. light grey to black mudstones, siltstones, very fine and fine sandstones. No palynomorphs have been extracted from coal samples. Carefully controlled oxidation and bleaching of the highly carbonized assemblages can often clear microfossils Thalassiosira torokina n. sp. sufficiently to allow identification to species level. Preserva- (diatom) and its significance in tion varies from barely recognizable black skeletal microfossils to relatively well preserved yellow-brown pollen Late Cenozoic biostratigraphy grains and spores readily assignable to species level without the need for clearing procedures. Palynomorphs probably differ in their susceptibility to thermal alteration, resulting HOWARD THOMAS BRADY in a bias in relative frequencies of species which should be taken into consideration when comparing the more poorly Department of Geology preserved of the antarctic assemblages with well preserved Northern Illinois University assemblages from other Gondwana continents. DeKalb, Illinois 60115 Palynomorph preservation shows no apparent relation- ship to proximity of dolerite, apart from the absence of microfossils within a few meters of a sill. Some stratigraphic Wrenn (1977) dates the lowermost intervals of Dry Valley sections free of dolerite have produced only barren samples, Drilling Project (DVDP) holes 10 (155.40 to 185.47 meters) while other sections containing several sills 50 to 200 meters and 11 (202.45 to 328 meters) as late Miocene to Early thick have yielded assemblages of moderately well preserved Pliocene. Diatoms have now been recovered from the sandy microfossils. Plots of the state of preservation against mudstones and siltstones of these intervals. Diamictites (in distance from and thickness of sills show random distribu- hole 11, 202.45 to 328 meters) contain foraminifera but no tion of barren, poor, and good samples. Schopf and Long diatoms. The thick ice tongues that produce diamictites pre- (1966) also found no systematic variation in coal rank (fixed vent photosynthesis, and this inhibits planktonic diatom carbon and British thermal units) with distance away from a production. sill. The effects of high temperature contact metamorphism The occurrence of Thalassiosira oestrupi (Ostenfeld) seem therefore to be restricted to strata immediately adja- Proskina-Lavrenko indicates an early Pliocene age for hole cent to dolerite sills. This seems to be an anomaly. 11, 197 to 242 meters. For future palynological work on the Beacon Supergroup Thalassiosira torokina n. sp. (figure) occurs with T. in the Transantarctic Mountains we suggest that light grey oestrupi. It is present in hole 10 between 157.76 and 183 to black mudstone to fine sandstone samples are most likely meters and in hole 11 between 202 and 291 meters. Neither to be productive. Collecting from sections with little or no taxa is known between 291 meters and the bottom (328 dolerite does not guarantee productive samples. meters) of the drilled succession in hole 11. This research is supported by National Science Founda- T. torokina n. sp. is in Deep Sea Drilling Project (DSDP) tion grant DPP 76-83030. This continues studies formerly hole 266, core barrels 8/1 through 9/4, and in Eltanin core done under National Science Foundation grant AG-82 to the 34-19, 1.50 to 2.50 meters. In DSDP hole 266 this new U.S. Geological Survey G.M. Schopf), and an Ohio State species ranges from the top of the b event in the Gilbert to University postdoctoral fellowship by R. A. Kyle. the Epoch 5 boundary. In Eltanin core 34-19, the species oc- curs in the interval below the c events in the Gilbert References (Watkins and Kennett, 1972). I examined the Miocene in- terval in DSDP holes 279 anbd 266, and it seems that T. torokina does not range down into the Miocene. Since this species was only abundant in DSDP hole 266 in the earliest Helby, R.J., and C.T. McElroy. 1969. Microfloras from the Devo- Pliocene, it is suggested that the lowermost intervals of nian and Triassic of the Beacon Group, Antarctica. N.Z.Journal of Geology and Geophysics, 12 (2&3): 376-382. DVDP holes 10 and 11 are 4.5 to 5.0 million years old. Kemp, E.M. 1972. Lower Devonian palynomorphs from the Horlick The presence of diamictites in DVDP hole 11 and their Formation, Ohio Range, Antarctica. Pala eontographica, 139B: absence in DVDP hole 10 indicate that in the early Pliocene 105-124. ice tongues advanced from the polar plateau (Taylor glacia- Kyle, R.A. In press. Palynostratigraphy of the Victoria Group of tions of Denton and Armstrong, 1968; Denton et al., 1970) south Victoria Land, Antarctica. N.Z. Journal of Geology and and floated within the valley fjord 4 kilometers from the Geophysics, 20(5). mouth of the valley. Miocene sediments may underlie this Norris, G. 1965. Triassic andJurassic miospores and acritarchs from early Pliocene succession, as neither hole 10 nor hole 11 the Beacon and Ferrar Groups, Victoria Land, Antarctica. N.Z. penetrated to basement. Journal of Geology and Geophysics, 8(2): 236.277. The species description is as follows. 122 ANTARCTIC JOURNAL.
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