As part of initiatives by the Australian and Queensland Governments to support energy security and mineral exploration, a deep seismic reflection and magnetotelluric survey was conducted in 2007 to establish the architecture and geodynamic framework of north Queensland. With additional support from AuScope, nearly 1400 km of seismic data were acquired along four lines, extending from near Cloncurry in the west to almost the Queensland coast.

Elan Bank, a large western protrusion of the Kerguelen Plateau, is a microcontinent that originally lay between India and Antarctica in Gondwana. The acticle analyses seismic stratigraphy and crustal structure of the Elan Bank and discusses tectonic history of this feature. The paper contributes to understanding of dispersal and accretion of continental fragments in association with both plate tectonics and hotspot activity has likely been a significant process for much of Earth's history.

This Australian volcanoes image set comprises 15 images on CD-ROM with accompanying descriptive text and student question/s for each image. Learn the history of Australia's hot spot volcanoes over 60 million years and examine 9 Australian volcanoes in detail. Suitable for primary levels Years 5-6 and secondary levels Years 7-10

Subduction of oceanic crust at an unusually low angle (flat-subduction) has been proposed as a general model for the growth of continental crust older than about 2.5 Ga. At modern zones of flat subduction, magmatic additions to new crust come from partial melting of both the subducting oceanic crust (slab) and the thin wedge of mantle above the slab. Evidence for both a slab and wedge source is commonly preserved in some, but not all, late Archaean (3.0-2.5 Ga) terrains, but we find little evidence that a mantle wedge contributed to early Archaean (>3.0 Ga) crustal growth. In contrast to most modern terrains and some late-Archaean terrains, early Archaean continental crust evolved through direct melting of thick mafic crust.

Regional geology of the Eastern Goldfields and component terranes; deformation history and structural architecture; previous seismic interpretations; granitoids; tectonics constraints imposed by greenstones; tectonic settings and models

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The lower part of the Pilbara Supergroup records 300 million years of voluminous basaltic magmatism from c. 3.515 to 3.24 Ga. The basalts are divided into two compositionally distinct (high-Ti and low-Ti) but contemporaneous and interbeded types. Compared to the low-Ti basalts, the high-Ti basalts (TiO2>0.8 wt%) have relatively high concentrations of HFSE and REE, are generally more Fe-rich, have very low Al2O3/TiO2 (18.7 - 8.9) and high Gd/Yb ratios (1.12-2.23) - they have affinities with Al-depleted (or Barberton-type) komatiites and komatiitic basalts that formed during high pressure melting in particularly hot mantle plumes. The composition of these basalts, and their source, did not change significantly throughout the 300 m.y. period of basalt eruption. In contrast, low-Ti basalts show distinct secular trends to lower concentrations of incompatible trace elements and lower ratios of La/Sm, La/Gd, La/Yb and Gd/Yb that reflect a source progressively more depleted than NMORB source. Gd/Yb ratios in the younger basalts are as low as 0.67, well below estimates for modern depleted mantle (0.98), and reflect a strongly depleted source. The source for the low-Ti basalts formed from the depleted residue of the plumes that produced the earliest high-Ti basalts. It remained isolated from the convecting asthenosphere throughout the 300 m.y. period of basaltic magmatism, but remelted each time one of several younger plumes (the sources for contemporaneous high-Ti basalts) impinged on the lithospheric mantle. The result was a thick pile of interbedded high- and low-Ti basalt. A complimentary, thick, depleted, and buoyant sub-continental lithospheric mantle (SCLM), developed, in situ from the Low-Ti basalt source, and also by accumulation of the plume source for the high-Ti basalts. These results support models for Palaeoarchaean protocrust formation through extensive mantle plume magmatic events, and models that suggest that the Archaean SCLM formed at the same time as early voluminous mafic magmatism. Basalts in the lower Pilbara Supergroup are typically not highly contaminated by felsic crust. Neither the degree of contamination nor the proportion of contaminated rocks appears to have increased significantly with decreasing age, despite clear evidence that the volume of co-existing felsic material increased significantly over that period. Likewise, there is no evidence for subduction modification of mantle sources until the youngest basalts of the uppermost Pilbara Supergroup erupted at c. 3.0 Ga.

This book describes the evolution of the Australian continent over the last 600 million years. In particular, it focuses on the palaeogeography of Australia. This book is the result of several years' work by a dedicated group of people. The work has begun at the Australian National University by Dr Peter Cook, then the initiative was continued at the BMR. Later work has expanded the study from the Australian continent into the broader context of the supercontinent of Gondwana, and also into more detailed studies of smaller areas of the Australian continental margin. - comprises a 96 page, full colour book with sections on geological time, plate tectonics, the break up of Gondwana, climate and sea level change, evidence for ancient environments & Australia's geological framework. - 70 palaeogeographic maps; Cambrian through to Quaternary - foldout legend - 6 page glossary of relevant terms

Comparison of Pb and Nd isotopes of the well-endowed Abitibi-Wawa Subprovince with the poorly endowed Eastern Goldfields Province implies that volcanic-hosted massive sulfide (VHMS) endowment in Archean terrains is controlled by crustal character. The Abitibi-Wawa Subprovince contains mostly primitive crust formed in a wide extensional environment. The high heat flow, promoted by thin crust and high level intrusions, and the extensional structures that characterize such an environment encouraged the formation of extensive VHMS deposits. In contrast, extensional environments are limited to a relatively narrow zone in the Eastern Goldfields Province. Although this zone contains VHMS deposits, they are not abundant enough to create high endowment. Provinciality of Pb isotopes in lode Au deposits from near Leonora in the Eastern Goldfields Province supports the concept of a rift-like zone.