Different styles of modern and ancient non-collisional orogens and implications for crustal growth: a Gondwanaland perspective

Abstract

Non-collisional, convergent margin orogens are generally called accretionary orogens, although there may not have been horizontal accretion across the plate boundary. We revive the term non-collisional orogen and use a Gondwanaland perspective to discuss different types. On the northern margin of the Australian Plate, the New Guinea non-collisional, accretionary orogen was formed by large-scale terrane accretion across an advancing plate margin. On the eastern margin, the Southwest Pacific Orogen is a non-collisional and non-accretionary orogen, involving virtually no horizontal transfer of material across its eastward-retreating plate boundary. In the Tasmanides, the Lachlan Orogen, commonly described as an accretionary orogen, is another non-collisional, non-accretionary orogen developed behind the plate margin after major Cambrian rollback, with resultant backarc basins filled mainly by quartz-rich turbidites subsequently recycled. The outboard New England Orogen is a non-collisional but accretionary orogen, marked by the frontal accretion of continental margin arc detritus, subsequently recycled into younger arcs. The Permian to Cretaceous Rangitata Orogen of New Zealand is an ?oblique non-collisional, accretionary orogen in which Permian-Triassic sediments of the accretionary wedge have no link with inboard (near) arc terranes. Late Jurassic to Cretaceous parts were sourced by a combination of first cycle volcanogenic detritus passing through the forearc basin together with recycling of the exhumed parts of the wedge. All non-collisional orogens involve continental growth, but only the New England Orogen and to a lesser extent the New Guinea Orogen involve significant crustal growth.

The mechanisms underpinning Cenozoic intraplate volcanism in eastern Australia: Insights from seismic tomography and geodynamic modeling

“…To the north of the CP, the thicker lithosphere is likely associated with stable shield region of the continent, although it appears to extend further east than previously thought [e.g., Fishwick et al, 2008], possibly due to the presence of a Precambrian continental sliver beneath the southern Thomson Orogen [Glen et al, 2013[Glen et al, , 2016. The New England Orogen, which lies at the very eastern edge of the continent, exhibits zircon 10.1002/2017GL074911 age dates which also suggest the presence of an older continental fragment [Aitchison et al, 1992;Glen et al, 2016], the location of which approximately corresponds with the locally thick zone that forms the eastern margin of C2 (Figure 2b).…”

“…For example, the Curnamona Province (CP), which stands out clearly in total magnetic intensity (Figure b), appears as a locally thick region of lithosphere (Figure a), which is consistent with its Palaeoproterozoic‐Archean origins [ Page , ; Hand et al , ]. To the north of the CP, the thicker lithosphere is likely associated with stable shield region of the continent, although it appears to extend further east than previously thought [e.g., Fishwick et al , ], possibly due to the presence of a Precambrian continental sliver beneath the southern Thomson Orogen [ Glen et al , , ]. The New England Orogen, which lies at the very eastern edge of the continent, exhibits zircon age dates which also suggest the presence of an older continental fragment [ Aitchison et al , ; Glen et al , ], the location of which approximately corresponds with the locally thick zone that forms the eastern margin of C2 (Figure b).…”

“…NVP = Newer Volcanics Province. Black lines indicate the approximate locations of Palaeozoic orogen boundaries [ Glen et al , ]. Although not shown, recent evidence points to the presence of early to middle Miocene lava fields south of the NVP in Bass Strait [ Reynolds et al , ].…”

“…NVP = Newer Volcanics Province. Black lines indicate the approximate locations of Palaeozoic orogen boundaries [Glen et al, 2016]. Although not shown, recent evidence points to the presence of early to middle Miocene lava fields south of the NVP in Bass Strait [Reynolds et al, 2017]. convection in the upper mantle, the composition of erupted material, and the pathway(s) taken by melt on route to the surface [e.g., Ashwal and Burke, 1989;King and Anderson, 1998;Huang et al, 2002].…”

Two giants of geology: Kevin Charles Antony Burke and John Frederick Dewey

“…(17) A paper by Glen et al (2016) discusses crustal growth processes in modern and ancient orogenic belts, using a Gondwanaland perspective. In their discussion, the authors focus on the orogenic belts in northern Australia, New Guinea, Southwest Pacific, Tasmania, and New Zealand.…”