Amphibolites and related rocks from the Wongwibinda metamorphic complex, northern N.S.W., Australia

Stephenson, N. C. N.; Hensel, H. D.

doi:10.1016/s0024-4937(82)80006-6

Cited by 17 publications

(8 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…High-temperature metamorphic complexes in the southern New England orogen (Wongwibinda and Tia complexes; Fig. 7) are fault-bounded, and their possible relationship to extensional tectonism is not fully understood (Stephenson and Hensel, 1982;Danis et al, 2010;Craven et al, 2012;Fukui et al, 2012). Nevertheless, there is evidence that rocks were subjected to an elevated geothermal gradient with peak metamorphism (amphibolite-facies) dated at 296.8 ± 1.5 Ma (Craven et al, 2012).…”

Section: (C) Relative Probability (Red) and Number Of Concordant Analmentioning

confidence: 99%

Provenance of the Early Permian Nambucca block (eastern Australia) and implications for the role of trench retreat in accretionary orogens

Shaanan

Rosenbaum

Wormald

2015

Geological Society of America Bulletin

View full text Add to dashboard Cite

The New England orogen of eastern Australia is characterized by tight orogenic curvatures (oroclines). Oroclinal bending commenced in the Early Permian during a period of extension that involved crustal melting, widespread emplacement of S-type granitoids, high-temperature metamorphism, exhumation of metamorphic complexes, extensional faulting, and development of rift basins. One of these basins is the Early Permian Nambucca block, which is situated in the "core" of the oroclinal structure, but its origin and time of deposition are poorly constrained. Here, we present new U-Pb ages of detrital zircons from the Nambucca block, which include age populations as young as 299 and 285 Ma, confi rming the Early Permian deposition of the succession. Additional Devonian-Carboniferous and Precambrian ages indicate that detritus was mainly derived from the New England subduction complex and cratonic Gondwana. The range of ages suggests that the Nambucca Basin received detritus from both arc and continent and that deposition occurred in a back-arc setting. Given the coeval formation of the Nambucca Basin and the New England oroclines, we propose that this back-arc extensional basin was controlled by trench retreat, which resulted in "Mediterranean-style" orogenic curvatures along the plate boundary of eastern Gondwana. The recognition of a genetic link between oroclinal bending and back-arc extension may explain how accretionary orogens, such as the eastern Australian Tasmanides, were able to obtain an anomalous width without a substantial contribution of accreted exotic terranes. A similar mode of tectonism may have played an important role in other accretionary orogens.

show abstract

Section: (C) Relative Probability (Red) and Number Of Concordant Analmentioning

confidence: 99%

Provenance of the Early Permian Nambucca block (eastern Australia) and implications for the role of trench retreat in accretionary orogens

Shaanan

Rosenbaum

Wormald

2015

Geological Society of America Bulletin

View full text Add to dashboard Cite

show abstract

“…Typical lithologies include deep marine volcaniclastic turbidites, cherts and argillites, mafic volcanic rocks, and olistostromal deposits containing slabs of limestone, basalt, andesite and siltstone (Leitch and Cawood, 1980;Cawood, 1982;Fergusson, 1984). Rocks were subjected to varying degrees of metamorphism ranging from prehnitepumpellyite/lower greenschist (e.g., Texas Beds and Coffs Harbour Association, Korsch, 1978) to amphibolite (Tia and Wongwibinda metamorphic complexes; Binns, 1966;Stephenson and Hensel, 1982; Phillips et al, 2008;Danis et al, 2010;Craven et al, 2012) (Figure 1b). High-pressure rocks are relatively rare, but are recognised as an earlier blueschist assemblage in the Tia metamorphic complex (Phillips et al, 2008).…”

Section: Introductionmentioning

confidence: 99%

Oroclines of the southern New England Orogen, eastern Australia

Rosenbaum¹

2012

Episodes

View full text Add to dashboard Cite

Orocline (Figure 1d). This orocline has been suggested based on (1) paleomagnetic data showing block rotations of forearc basin terranes around vertical axes (Geeve et al., 2002; Klootwijk, 2009; Cawood et al., 2011b); (2) the recognition of a contorted serpentinite belt (Korsch and Harrington, 1987); and (3) the curved structure delineated by Early Permian (298-288 Ma) granitoids (Rosenbaum, 2010; Rosenbaum et al., 2012). Nevertheless, structural information supporting the existence of this orocline is more ambiguous. Based on the lateral continuation of early Permian granitoids, an even more complex structural model that involves four bends, has been proposed (Rosenbaum, 2010; Rosenbaum et al., 2012) (Figure 1e). The suggested fourth bend has been named the Nambucca Orocline (Rosenbaum, 2010). The kinematics associated with the development of the New England oroclines is relatively poorly constrained, with only patchy structural, paleomagnetic and geochronological data. In this respect, 'orocline' is used here in a general sense, as referring to orogenic curvatures rather than the strict sense that implies a secondary bending of an originally linear belt (Weil and Sussman, 2004). This paper aims to highlight the structure of the oroclines by outlining the spatiotemporal distribution of different tectonic elements within the southern NEO. This will be followed by a discussion on the large-scale tectonic implications of this spectacularly contorted orogenic structure. Tectonic elements Devonian-Carboniferous subduction complex The greater part of the exposed southern NEO is a Devonian-Carboniferous convergent margin complex (Figure 2) comprising forearc basin rocks of the Tamworth Belt and correlative terranes, and accretionary metasedimentary rocks of the Tablelands Complex. These domains are separated from each other by a tectonic contact, the Peel-Manning Fault System (PFZ and MFZ in Figure 1b), along which a lithological assemblage of serpentinites, blueschists and eclogites, is exposed. This assemblage, hereinafter referred to as the 'serpentinite belt' (Korsch and Harrington, 1987; Aitchison et al., 1994; Och et al., 2003), is most prominent along a long (c. 150 km), A series of tight bends (oroclines) are recognised in the late Paleozoic-early Mesozoic southern New England Orogen between Brisbane and Newcastle, but their exact geometry and tectonic evolution are still debated. This contribution provides an outline of the different tectonic elements within the orogen and the relationships of these elements with the oroclinal structure. Pre-oroclinal tectonic elements were derived from a Devonian-Carboniferous subduction zone, and include forearc basin terranes and accretionary wedge rocks that are separated from each other by a narrow belt of serpentinites and high-pressure rocks. Rocks are predominantly steeply dipping and their map-view pattern delineates three bends: the Z-shaped Texas and Coffs Harbour oroclines in the north and the U-shaped Manning Orocline in the south. During the early Permian (298-2...

show abstract

“…Such rocks are notably enriched in Ca relative to typical amphibolites (Williams 1982). Ca-rich, clinopyroxene-bearing metaigneous amphibolites have also been described from a number of other areas (Evans and Leake 1960;McGregor 1973;Stephenson and Hensel 1982). These examples have all been interpreted as metavolcanic rocks in which local Ca-enrichments are best explained as results of premetamorphic hydrothermal alteration.…”

Section: Discussionmentioning

confidence: 96%

Metamorphic carbonate–mafic amphibolite interactions from Arinteiro, northwest Spain

Williams

1987

Geological Journal

View full text Add to dashboard Cite

Some contacts between interlayered marbles and amphibolites at the Arinteiro copper mine are associated with zoned metasomatic calc-silicate assemblages. Texturcs indicate that formation o f thc calc-silicate zones involved mass transfer over distances up to 15 cm and that pore fluid solution (infiltration) may have been a significant reaction mechanism. The sequence of minerals is very similar to previously described products of metasomatic interactions between marbles and pelitcs. Similar metasomatic processes involving primary concentrations of carbonates can be invoked t o explain the common occurrence o f zoned calc-silicate patches and folia in metaigneous amphibolites both nciir Arinteiro and in other terrains.

show abstract

Amphibolites and related rocks from the Wongwibinda metamorphic complex, northern N.S.W., Australia

Cited by 17 publications

References 54 publications

Provenance of the Early Permian Nambucca block (eastern Australia) and implications for the role of trench retreat in accretionary orogens

Provenance of the Early Permian Nambucca block (eastern Australia) and implications for the role of trench retreat in accretionary orogens

Oroclines of the southern New England Orogen, eastern Australia

Metamorphic carbonate–mafic amphibolite interactions from Arinteiro, northwest Spain

Contact Info

Product

Resources

About