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  • Legacy product - no abstract available

  • Legacy product - no abstract available

  • <p>The present Correlation Chart summarizes the published information concerning the stratigraphy of the Cambrian and Ordovician of Australla as outlined in the "Notes" at the end of this record. The Chart is incomplete, but it can be amplified concurrently with the publication of new information from the field . The main part of the chart is its "Time-Scale", which also is subject to improvement and amplification. The main objective of forthcoming studies is a more detailed subdivision of the upper two-thirds of the Upper Cambrian and of the Ordovician. But even now the scale is fully applicable for correlation of the deposits of central Australia (MacDonnell Ranges to western Toka Range region), as seen from fossil collections and field studies. <p>The author has had the opportunity to communicate orally to his colleagues his ideas concerning the meaning, principles, and methods of geological correlation. These ideas are now summarized to give a brief outline of the philosophical background to the present Chart.

  • <p>A basement of Precambrian volcanic and granitic rocks is overlain by two sequences of shallow-water sedimentary rocks regarded as of Upper Proterozoic age, and by a sequence of terrestrial and paludal or lacustrine sedimentary rocks of Upper Jurassic to Lower Cretaceous age. The older Upper Proterozoic sequence contains volcanics and intrusives and has been moderately folded. The younger Upper Proterozoic sequence has been weakly folded. <p>Remnants of Miocene (?) laterite occur near the headwaters and on the interfluves of streams flowing towards the Gulf of Carpentaria. <p>Faults (both normal and transcurrent) and joints with a dominant north-west trend are numerous. The most prominent fault, the Calvert Hills fault is transcurrent, quartz-filled in places, and trends north-west across the sheet. <p>The Precambrian basement rocks contain small deposits of uranium, copper, tin and gold. The older sequence of Upper Proterozoic rocks contains small deposits of uranium and copper. The younger sequence contains small deposits of copper and manganese. Some of the sedimentary rocks are aquifers and would supply adequate quantities of bore water for stock. <p>Two second order relief forms occur; one the dissected country drained by streams flowing to the Gulf of Carpentaria, the other the tableland country drained by streams flowing into an internal drainage basin. Fossil erosion surfaces are present in the area. Some land-forms are controlled by structure.

  • Legacy product - no abstract available

  • Legacy product - no abstract available

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