The record and stratigraphie implications of organic-walled microfossils from the Ediacaran (terminal Proterozoic) of South Australia

Abstract

Two assemblages of organic-walled microfossils have been recognized in drillcore samples from the late Proterozoic Rodda Beds in theeastern Officer Basin, South Australia. The fossils include tube-like remains and large, simple and sculptured acritarchs. Lithostratigraphic studies and seismic information, in conjunction with previous (albeit limited) acritarch finds, allow local correlation of the Rodda Beds with Ediacaran or terminal Proterozoic sequences in the northern Adelaide Fold Belt (site of the nominated Ediacaran stratotype). The new palynofloras are comparable withacritarch assemblages in the Amadeus Basin of central Australia, and suggest tentative correlations with sequences in China and the U.S.S.R. The presence of isotopically heavy marine carbonate in the lower fossiliferous horizons of the Rodda Beds (σ13CPDB = +3 to +6%0) is consistent with isotopic data from the equivalent interval in China. In contrast, the upper fossiliferous strata occur higher in the Rodda Beds where carbonate is significantly lighter (σ13CPDB = -1 to + 3%0).

Taphonomy of Ediacaran Acritarchs From Australia: Significance for Taxonomy and Biostratigraphy

“…Generally only one or two TAPHONOMY OF EDIACARAN ACRITARCHS FROM AUSTRALIA specimens per sample were recovered using standard palynological techniques. However, using the modified method, Ͼ100 specimens were recovered from small samples (ϳ25 g); for example, compare material from Murnaroo 1 described by Jenkins et al (1992) with Willman et al (2006).…”

“…1, 2) (Damassa and Knoll, 1986;Zang andWalter, 1989, 1992;Jenkins et al, 1992;Zang, 1995;Grey et al, 2003;Grey, 2005;Willman et al, 2006;Willman and Moczydłowska, 2008). Preservation ranges from excellent to severely degraded, and some of the observed variability among samples is attributable to taphonomic alteration.…”

Remarkable preservation of microbial mats in Neoproterozoic siliciclastic settings: Implications for Ediacaran taphonomic models

“…One explanation for the preservation of fossils in negative relief on bedding plane soles ('Flinders-style' preservation of has been that organisms possessed a resistant external integument (Wade, 1968;Seilacher, 1984;1989;Jenkins et al, 1992;Retallack, 1994;Crimes et al, 1995;Retallack, 2007), although observations of overfolded, bent and torn specimens (Runnegar, 1982;Gehling et al, 2005;Brasier & Antcliffe, 2009) can be taken to suggest otherwise (Fig. 2D).…”

Carbon isotope geochemistry and palaeontology of Neoproterozoic to early Cambrian siliciclastic successions in the East European Platform, Poland

“…In this regard, continuous successions embracing this time interval have been studied extensively in China (Hsü et al 1985;Lambert et al 1987), Siberia (Magaritz, Holser & Kirschvink, 1986;Magaritz, 1989;Kirschvink et al 1991;Magaritz et al 1991;Brasier, Khomentovsky & Corfield, 1993;Brasier et al 1994;Kaufman & Knoll, 1995;Knoll et al 1995a,b), Morocco (Tucker, 1986;Renner, 1994), East Greenland and Spitsbergen (Knoll et al 1986;Fairchild & Spiro, 1987), the Lesser Himalaya (Aharon, Schidlowski & Singh, 1987), Australia (Tucker, 1989;Jenkins et al 1992;Walter et al 1995), Iran ), Namibia (Kaufman et al 1991) and the U.S. and Canada (Brasier, Anderson & Corfield, 1992;Grant, 1992;Kaufman, Knoll & Awramik, 1992;Peters, Wickham & Miller, 1992;Strauss et al 1992a;Narbonne, Kaufman & Knoll, 1994;Smith et al 1994). Most of these successions consist predominantly of platform carbonate deposits, and isotope data exist primarily for carbonate carbon and only to a lesser extent for organic carbon.…”