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RST Apology to Tasmanian Aboriginal people 2021.

A Cretaceous phonolite dyke from the Tomahawk River, northeast Tasmania

Papers & Reports

Summary

Field mapping and indicate that a phonolite which intrudes Devonian granite in the upper Tomahawk River area, Tasmania, is 3.2 km long and with a true thickness of 10-15 m. The rock contains of anorthoclase, sparse fayalitic olivine and low-Ti and rare biotite in a alkali feldspar laths, with interstitial clinopyroxene to amphibole or analcime and accessory apatite. It is peralkaline and evolved, even for phonolites, with very and CaO, and high and incompatible elements. However, relatively high Sr and Ba and the absence of a negative Eu anomaly suggest little feldspar fractionation in its petrogenesis. Its Late Cretaceous age 80.4 ± 1.6 Ma, 4oAr/39Ar plateau 75.8 ± 0.3 Ma, 4oAr/39Ar total fusion 76 ± 3.1 Ma) and geochemistry are unique for Tasmania and it represents a recognised, although very minor, igneous episode. It may be related to a change in dynamic regime following continental rifting, the opening of the Tasman Sea and the subsidence of Bass Basin.

 

Keywords:

Royal Society of Tasmania, RST, Van Diemens Land, natural history, science, ecology, taxonomy, botany, zoology, geology, geography, papers & proceedings, Australia, UTAS Library

Acknowledgement of Country

The Royal Society of Tasmania acknowledges, with deep respect, the traditional owners of this land, and the ongoing custodianship of the Aboriginal people of Tasmania. The Society pays respect to Elders past, present and emerging. We acknowledge that Tasmanian Aboriginal Peoples have survived severe and unjust impacts resulting from invasion and dispossession of their Country. As an institution dedicated to the advancement of knowledge, the Royal Society of Tasmania recognises Aboriginal cultural knowledge and practices and seeks to respect and honour these traditions and the deep understanding they represent.

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On 15 February 2021, the Royal Society of Tasmania offered a formal Apology to the Tasmanian Aboriginal people.