Hitta hit:
T-bana: Universitetet
Frescativägen 40

Ordinarie öppettider:
Tisdag–fredag 11–17
Lördag–söndag 10–18

  • Huvudmeny
PERMIAN PLANTS OF AUSTRALIA

Mersey Coal Measures

Specimens by taxa

Flora of the Mersey Coal Measures, Latrobe, Tasmania
Coal is found in thin seams and as comminuted carbonaceous material in alluvial plain sequences at Latrobe in central-north Tasmania. These deposits are traditionally assigned to the “Lower Freshwater Sequence" considered by Martini & Banks (1989) to be laterally equivalent to the Mersey Coal Measures of the lower Parmeener Supergroup. These coal-bearing strata host a lower Stage 3b palynoflora (Bacon 1995) considered to be of Sakmarian—Artinskian (Early Permian) age (Briggs, 1998). The coals were deposited in alluvial plain to paralic environments under cold climatic conditions. Glacial dropstones and a cold-water Eurydesma fauna occur in associated marine sediments. This area is also notable for yielding Tasmanite — a type of sapropelic coal rich in the alga Tasmanites (see Revill et al. 1994). Coal seams within the Mersey Coal Measures and equivalents are thin and discontinuous. They were intermittently mined from the mid-19th to mid-20th centuries (Bacon 1995). The fossil flora of the Mersey Coal Measures has never been thoroughly described, although White (1986) illustrated Glossopteris leaves and an ovuliferous reproductive structure from the Latrobe area. The two samples from Latrobe, Tasmania, held in the NRM collections host well-preserved pinkish-brown Glossopteris leaf impressions on a pale grey shale matrix.

References

Bacon, C.A. 1995. Tasmania Basin. In Geology of Australian coal basins. C.R. Ward, H.J. Harrington, C.W. Mallett & J.W. Beeston, eds, Geological Society of Australia, Coal Geology Group, Special Publication 1, Sydney, 441-453.

Briggs D. J. C. 1998. Permian Productina and Strophalosiidina from the Sydney-Bowen Basin and the New England Orogen: systematics and biostratigraphic significance. Association of Australasian Palaeontologists Memoir 19, 1-258.

Martini,  I.P. & Banks, M.R. 1989. Sedimentology of the cold-climate, coal-bearing, Lower Permian "Lower Freshwater Sequence" of Tasmania. Sedimentary Geology 64, 25-41.

Revill, A.T., Volkman, J.K., O'Leary, T., Summons, R.E., Boreham, C.J., Banks M.R. & Denwer, K., 1994. Hydrocarbon biomarkers, thermal maturity, and depositional setting of tasmanite oil shales from Tasmania, Australia. Geochemica et Cosmochemica Acta 58, 3803-3822.

White, M.E., 1986. The Greening of Gondwana. The 400 Million Year Story of Australia´s plants. Reed, Frenchs Forest, NSW, 256 pp.

Map of Australia showing the distribution of Permian sedimentary basins and indicating the location of Latrobe, Tasmania.