High-P amphibolite-facies metamorphism in the Adrar–Souttouf Metamafic Complex, Oulad Dlim Massif (West African Craton margin, Morocco)

Late-Proterozoic to Paleozoic history of the peri-Gondwana Calabria–Peloritani Terrane inferred from a review of zircon chronology

U-Pb analyses of zircon from ten samples of augen gneisses, eight mafic and intermediate metaigneous rocks and six metasediments from some tectonic domains along the Calabria-Peloritani Terrane (Southern Italy) contribute to knowledge of peri-Gondwanan evolution from Late-Proterozoic to Paleozoic times. All samples were equilibrated under amphibolite to granulite facies metamorphism during the ...

Paleoproterozoic high-pressure metamorphism in the northern North China Craton and implications for the Nuna supercontinent

The connection between the North China Craton (NCC) and contiguous cratons is important for the configuration of the Nuna supercontinent. Here we document a new Paleoproterozoic high-pressure (HP) complex dominated by garnet websterite on the northern margin of the NCC. The peak metamorphism of the garnet websterite was after ∼1.90 Ga when it was subducted to eclogite facies at ∼2.4 GPa, then e...

An albite-anorthite assemblage in low-grade amphibolite facies rocks

Poikiloblastic amphibole schists from an ophiolite series in the vicinity of the Tertiary Bergell granite contain the assemblage albite (An 0)-anorthite (An 95), actinolite-pargasite, together with clinozoisite. TEM illustrates how large andesine crystals with a periodic APB (anti-phase boundaries) structure of e plagioclase change over a few hundred angstroms to pure albite and pure PT anorthi...

U^Pb isotopic behaviour of zircon during upper-amphibolite facies £uid in¢ltration in the Napier Complex, east Antarctica

Understanding the factors that contribute to U^Pb discordance in zircon is essential for interpreting isotopic data and for assessing the validity of concordia intercept ages. Modification caused by interaction with metamorphic fluids is often cited as a primary means by which significant or even complete isotopic resetting of U^Pb systematics in zircon might be achieved under subsolidus condit...

Role of the Hoggar massif in the West African monsoon onset