The origin of Archaean gneisses in the Fyfe Hills Region, Enderby Land; field occurrence, petrography and geochemistry

Thermal History of UHT Metamorphism in the Napier Complex, East Antarctica: Insights from Zircon, Monazite, and Garnet Ages

“…Many workers have argued, to the contrary, that the metamorphism at ∼2.5 Ga (often focused at ∼2.48-2.47 Ga) was the UHT event (e.g., Grew and Manton 1979;Sandiford and Wilson 1986;Sandiford and Powell 1986;Owada et al 1994;Grew 1998;Asami et al 2002;Carson et al 2002;Hokada et al 2003Hokada and Harley 2004). Carson et al (2002) pointed out that there are numerous ∼2.48-2.45-Ga SHRIMP U-Pb zircon ages from Tonagh Island despite the F 2 folding associated with the ∼2.5-Ga D 3 deformation having been less intense there than in the Fyfe Hills (Black and James 1983).…”

High-temperature Metamorphism and Crustal Anatexis

“…12.2) have been described extensively (Sheraton et al , 1987James & Black 1981;Black & James 1983;Black et al 1983a,b;Sandiford & Wilson 1983Harley & Black 1987) and will not be discussed here except within the context of the metamorphie history. Although layered paragneiss sequences of mainly supracrustal origin (Sheraton et al , 1987Sandiford & Wilson 1986) are important components of the complex, the terrane is dominated by felsic to intermediate orthogneisses. Although layered paragneiss sequences of mainly supracrustal origin (Sheraton et al , 1987Sandiford & Wilson 1986) are important components of the complex, the terrane is dominated by felsic to intermediate orthogneisses.…”

Protoliths of the Napier Complex in Enderby Land, East Antarctica; an overview and implication for crustal formation of Archaean continents

“…SB -1, High -Mg mafic gneiss (Sheraton and Black, 1981); SZ -1, Average of 3 phlogopite -free ultramafic rocks (Suzuki et al, 1999); SZ -2, Average of 5 phlogopite -bearing ultramafic rocks (Suzuki et al, 1999); OW -1, Hornblende -bearing lherzolitic peridotite (Owada et al, 2000; SH -1, Average of 10 mafic gneisses (Sheraton et al, 1987); SZ -3, Average of 5 quartz -free mafic gneisses (Suzuki et al, 1999); SZ -4, Average of 3 quartz -bearing mafic gneisses (Suzuki et al, 1999); OW -2, Average of 4 brown bornblende two pyroxene gneisses (Owada et al, 2000); OW -3, Average of 3 two pyroxene gneiises (Owada et al, 2000); OW -4, Average of 2 biotite -bearing two pyroxene gneiises (Owada et al, 2000); SH -2, Average of 21 depleted orthopyroxene felsic gneisses (Sheraton et al, 1987); SH -3, Average of 6 undepleted granitic gneisses (Sheraton et al, 1987); SZ -5, Average of 6 orthopyroxene felsic gneisses (Suzuki et al, 1999); SZ -6, Average of 7 garnet -poor felsic gneisses (Suzuki et al, 1999); SH -4, Sillimanite -sapphirine -osumilite -garnet granulite (Sheraton et al, 1987); SZ -7, Average of 3 garnet -sillimanite gneisses (Suzuki et al, 1999); SH -5, Sillimanite -garnet -osumilite( -spinel) quartzite (Sheraton et al, 1987); SZ -8, Average of 4 garnet -rich felsic gneisses (Suzuki et al, 1999). (Sandiford and Wilson, 1986) suggest its origin to be sedimentary rocks. Calc -silicate rocks with the mineral assemblage of diopside + plagioclase ± scapolite ± wollastonite ± grossular ± quartz ± calcite are restricted to Mt.…”