Deformation history and timing of granite emplacement in the Butchers Hill — Helenvale region, northern Hodgkinson Province, Queensland

Abstract

Granite plutons of the Whypalla Supersuite in the Butchers Hill -Helenvale region of north Queensland were intruded into the upper crust of the Hodgkinson Formation during contractional deformation associated with the Permian-Triassic Hunter-Bowen Orogeny. A four-stage structural history has been resolved for the area, with fabric overprinting relationships, porphyroblast-matrix microstructural geometries and isotopic ages being consistent with granite emplacement during D 4 shortening at ca 274 Ma. Microstructural relationships suggest the possibility of a minor syn-D 3 phase of granite emplacement. The deformation-emplacement history of the Butchers Hill -Helenvale area is consistent with that recognised regionally for the Hodgkinson Province, indicating province-wide synchronous syntectonic granite intrusion during a major phase of contractional deformation. Intense syn-emplacement deformation partitioning was ongoing in the country rocks during progressive D 4 and was associated with upward translation of country rock from the microscale to the macroscale along D 4 cleavages and shears. Kinematic indicators show that this progressive uplift, at the scale of the area examined, was east-side-up.

Temporal correlation of magmatic-tectonic events in the lower and upper crust in north-east Australia

“…The back-arc extension and related volcanism were followed by compressional tectonism and emplacement of Permian granitoids in the north-east Hodgkinson Province (Kositcin et al 2009). The coincidence of the Atherton lherzolite xenolith Sm-Nd isochron age of 275 Ma with the widespread 265 to 280 Ma granitoid magmatism (Bultitude and Champion 1992;Davis et al 2002) led Handler et al (2005) to suggest the growth of the lithosphere beneath the Atherton Province. Handler et al (2005) also proposed that the early Palaeozoic lithospheric mantle below the lower crust may have been removed and replaced with a new mantle during the Permian magmatism, whereas Murgulov et al (2011) suggested that the scattered fragments of the *1.75 and 1.23 Ga metasomatised cratonic lithosphere have been embedded within the lithospheric mantle column beneath the Atherton Province since at least *0.44 Ga. No age data have been obtained on the Atherton granulite xenoliths in this study.…”

Nd, Sr and Os isotope systematics in young, fertile spinel peridotite xenoliths from northern Queensland, Australia: A unique view of depleted MORB mantle?

“…For example, the Whypalla and Mt Alto Supersuite granitoids have ages of 265 to 280 Ma and ϳ270 Ma respectively (Bultitude and Champion, 1992;Davis et al, 1998Davis et al, , 2002, and the Wangetti Granite is ϳ273 to 285 Ma (Bultitude and Champion, 1992). Zhang et al (2001) reported Nd data for seven peridotites from various localities in the Atherton Tablelands.…”

The Onset of Gondwanide Orogeny in Eastern Australia: Insight From the Provenance of Syn‐Orogenic Strata in the New England Orogen (Australia)

“…The first evidence for major contractional tectonism marking the onset of the Gondwanide Orogeny in eastern Australia is recorded in the most outboard part of the orogenic belt, which is now partly preserved in geological units along the present‐day coastline (Figure 11a). The Mossman Orogen shows evidence of a regional contractional event that has been dated at 275–273 Ma by U‐Pb zircon geochronology of syn‐kinematic granitoids (Davis, Bell, et al., 2002; Davis, Hendreson, et al., 2002). In the Gympie Terrane (Figure 11a), the onset of orogenesis, prior to ∼263 Ma, is expressed by an abrupt change in the sedimentological record, involving an increased proportion of clastic sediments (Rosenbaum et al., 2020).…”