Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

M. F. Glaessner ¹

Affiliations
1 Department of Geology, University of Adelaide, AU

Abstract

A correlation of the Tertiary stratal sequences throughout the area from India to the islands of the Western Pacific and to Australia is attempted. As far as it concerns the Miocene, reference is made to Drooger's work on the stratigraphic distribution of Miogypsinidae and of pelagic Foraminifera. Apparent discrepancies reported from Formosa and Saipan are examined and the factual data are found to be compatible with Drooger's dating of the entry of Orbulina. Abundant information from south. eastern Australia on foraminiferal biostratigraphy is reviewed. Upper Eocene to Miocene foraminiferal zones can be regionally recognised, among them the important Globigerinoides bispherica zone. While its placing in the Helvetian in accordance with Drooger's findings in Europe is compatible with n!'!w observations and is tentatively accepted, a Burdigalian age cannot be ruled out on present evidence. The occurrence of Paleocene, Eocene and Miocene distinctive markers leads to the first fairly detailed correlation of Australian and Indo-Pacific Tertiary strata.

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M. F. Glaessner ¹

Affiliations
1 University of Adelaide, AU

Abstract

A brief review of recent datings of rocks of Early Cambrian and Late Precambrian age in the light of stratigraphic data and definitions leads to the conclusion that the most likely age of the base of the Cambrian is about 550-570 million years.

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M. F. Glaessner ¹

Affiliations
1 Department of Geology, University of Adelaide, AU

Abstract

Modern approaches to palaeontological problems are characteristically based on appreciation and analysis of geological as well as biological factors, tending to minimize the distinction between palaeobiological and biostratigraphic aspects of the subject. A rational approach to stratigraphic index fossils implies detailed evolutionary studies. Classification of fossils can no longer be expected to provide a definite name for every single object. The fossil record is incomplete not only in the sense of absence of formerly living organisms from the record hut also in the sense of incomplete representation of former biological systems by fossils. Physiological factors may be more important than shell or skeleton mechanics within these systems and also in the evolutionary origination of mineralized tissues. Faunal change, the basis of biostratigraphy, is being approached by microecological analysis rather than by empirical compilation of faunal lists. Methods are becoming more quantitative but guidance from biological models as to the significance of measurements and from some aspects of palaeontology as to the significance of samples is essential. Palaeontology is now a unified science, unique as the study of life processes in the past.

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