摘要:

The occurrence of ammonoids in the Lower Carboniferous rocks of eastern Australia is reviewed within a biostratigraphic framework provided by the brachiopod zones that have been summarized most recently by Jones & Roberts (1976). Ammonoid abundance is low at all stratigraphic levels. Nowhere are more than 20 specimens known at a locality, and usually there are only one or two. The group is too sparse to be used for local or regional correlation, and its main value is for the intercontinental correlation of a number of well separated horizons. The rocks dated range in age from middle Tournaisian (Tn2a) to late Visean V3c). Some relatively minor differences between ammonoid and conodont ages remain to be resolved. The biogeography is briefly discussed.

ISSN:0311-5518    

DOI:10.1080/03115518308619623

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Late Pleistocene mammalian faunas of Australia contain many extant taxa that indicate more mesic conditions. The presence of many disharmonious pairs of taxa in these faunas implies that the Pleistocene climate was more equable than at present. The climate began to change between 16,000 and 20,000 years B.P. to less equable conditions. Faunas younger than 16,000 years B.P. contain fewer disharmonious associations and show changes in the geographic distribution of many taxa approaching their present ranges. The disappearance of numerous disharmonious associations takes place at the same time as the extinction of the Pleistocene megafauna. The correspondence in time of the extinction of many Pleistocene taxa and the decrease in equability of the climate suggests that the cause of the widespread extinction 16,000 to 20,000 years ago lies in this climatic change which would lower plant productivity at certain seasons, putting stress on some components of the fauna.

ISSN:0311-5518    

DOI:10.1080/03115518308619624

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The medial Miocene Namba Formation at Lake Tarkarooloo, southeast of Lake Frome, South Australia, has yielded two nearly complete turtle shells that can be identified asEmydurasp., a pleurodire of the family Chelidae. Well preserved specimens of Australian Tertiary chelids are rare and these specimens form a significant addition to other specimens known from the Lake Eyre region of South Australia and Tasmania.

ISSN:0311-5518    

DOI:10.1080/03115518308619625

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The description of the type species,Anthoceras decorumTeichert & Glenister 1954, is emended, based on collections from Mt Arrowsmith, New South Wales. The generic description is emended to include changes made to the type species and attributes of Siberian and Chinese species. Range of the genus is Arenigian.

ISSN:0311-5518    

DOI:10.1080/03115518308619626

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Species of the strophomenoid brachiopodMaoristrophiahave hitherto been described only from Early Devonian strata, although Banks (in Talent & Banks, 1967) listed the genus from the Wenlockian to Ludlovian Austral Siltstone in Tasmania, and Garratt (1978, 1981) has reported Late Silurian occurrences in Victoria. That the genus appeared prior to the Devonian is confirmed by the description ofM. papilion. sp. from rocks of undoubted Wenlockian age in Canberra, Australia.

ISSN:0311-5518    

DOI:10.1080/03115518308619627

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor