Skip to main content
    • Aa
    • Aa
  • Get access
    Check if you have access via personal or institutional login
  • Cited by 4
  • Cited by
    This article has been cited by the following publications. This list is generated based on data provided by CrossRef.

    Beltrando, Marco Lister, Gordon S. Rosenbaum, Gideon Richards, Simon and Forster, Marnie A. 2010. Recognizing episodic lithospheric thinning along a convergent plate margin: The example of the Early Oligocene Alps. Earth-Science Reviews, Vol. 103, Issue. 3-4, p. 81.

    Fergusson, C. L. 2010. Plate-driven extension and convergence along the East Gondwana active margin: Late Silurian–Middle Devonian tectonics of the Lachlan Fold Belt, southeastern Australia. Australian Journal of Earth Sciences, Vol. 57, Issue. 5, p. 627.

    Hongn, Fernando D. Tubía, José M. Aranguren, Aitor Vegas, Néstor Mon, Ricardo and Dunning, Gregory R. 2010. Magmatism coeval with lower Paleozoic shelf basins in NW-Argentina (Tastil batholith): Constraints on current stratigraphic and tectonic interpretations. Journal of South American Earth Sciences, Vol. 29, Issue. 2, p. 289.

    Brown, Michael Clemens, John D. Pitcher, Wallace S. and Vernon, Ron H. 2005. Invited comments on Clemens's ‘Granites and granitic magmas’. Proceedings of the Geologists' Association, Vol. 116, Issue. 1, p. 17.

  • Earth and Environmental Science Transactions of the Royal Society of Edinburgh, Volume 95, Issue 1-2
  • March 2004, pp. 309-317

Growth of wedge-shaped plutons at the base of active half-grabens

  • S. W. Richards (a1) and W. J. Collins (a2)
  • DOI:
  • Published online: 01 July 2007

Combined field and geophysical data show that plutons from the Bega Batholith are elongate, meridional, wedge-shaped bodies which intruded during a period of regional east–west extension in the Palaeozoic eastern Lachlan orogen, eastern Australia. Plutons within the core of the batholith have intruded coeval, syn-rift sediments and co-magmatic volcanics. The batholith is bound by high-temperature, dip-slip faults, and contains several major NE-trending transtensional faults which were active during batholith construction. In the central part of the batholith, the Kameruka pluton is an asymmetric, eastward-thickening, wedge-shaped body with the base exposed as the western contact, which is characterised by abundant, shallow-dipping schlieren migmatites which contain recumbent folds and extensional shear bands. A shallow (<30°), east-dipping, primary magmatic layering in the Kameruka pluton steepens progressively westward, where it becomes conformable to the east-dipping basal migmatites. The systematic steepening of the layering is comparable to sedimentary units formed during floor depression in syn-rift settings. The present authors suggest that the wedge-shaped plutons of the Bega Batholith are the deeper, plutonic expression of a hot, active rift. The batholith was fed and sustained by injection of magma through sub-vertical dykes. Displacement along syn-magmatic, NE-trending faults suggests up to 25 km of arc-perpendicular extension during batholith construction. The inferred tectonic setting for batholith emplacement is a continental back-arc, where modern half-extension rates of 20–40 mm yr−1 are not unusual, and are sufficient to emplace the entire batholith in ∼1 Ma. This structural model provides a mechanism for the emplacement of some wedge-shaped plutons and is one solution to the ‘room problem’ of batholith emplace

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Earth and Environmental Science Transactions of The Royal Society of Edinburgh
  • ISSN: 1755-6910
  • EISSN: 1755-6929
  • URL: /core/journals/earth-and-environmental-science-transactions-of-royal-society-of-edinburgh
Please enter your name
Please enter a valid email address
Who would you like to send this to? *