Fluvial sequences and basin development in the northern Galilee Basin |
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| Authors: | A Van Heeswijck |
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| Institution: | Eurydesma Geological Service, 5 Blowering Court, Petrie, Qld 4502, Australia |
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| Abstract: | In the northern Galilee Basin, 10 third-order depositional sequences have been recognised in multi-suite geophysical logs of 16 wells and boreholes. Sequences can be subdivided into genetic systems tracts characterised by geometry, facies associations, types of bounding surface, parasequence set distribution and position within the sequence. Stacking trends of parasequence sets may be observed as a shift in the sand or shale base line. These sequences reflect basinal and hinterland tectonics with a subordinate climate and sea-level cycle signature. The initial development of the northern Galilee Basin in the upper Carboniferous reflects thermal subsidence that characterised the underlying Drummond Basin. This subsidence is overprinted by the commencement of foreland-basin tectonics associated with extension in the Bowen Basin. The foreland tectonics waned before a major regional uplift occurred in the northern Galilee Basin in the middle Permian. This uplift is associated with an early phase of the Hunter–Bowen Orogeny. A quiescent period where accommodation is controlled by sea-level changes is reflected in extensive development of mires. Renewed episodic contraction overprinted on thermal sag subsidence in the Lower Triassic reflects far-field tectonics associated with the Hunter–Bowen Orogeny. In the Upper Triassic, an end-phase event of the Hunter–Bowen Orogeny inverted the Galilee Basin. |
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| Keywords: | aggradational Carboniferous degradational fluvial sequence Permian system tract transitional Triassic |
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