Long‐lived high‐T, low‐P granulite facies metamorphism in the Arunta Region, central Australia

摘要: In situ LA–ICP–MS U–Pb monazite geochronology from the Boothby Hills in Aileron Province, central Australia, indicates that region records more than 80 Ma of high-T, low-P (HTLP) anatectic conditions during Early Mesoproterozoic. Monazite ages granulite facies rocks and leucosomes span interval 1576–1542 Ma. Pegmatites overprint regional gneissic fabric are interpreted to record last vestiges melt crystallization give between 1523 1513 Ma. Calculated P–T pseudosections suggest peak metamorphic excess 850 °C at 0.65–0.75 GPa. The retrograde evolution was characterized by a path involved minor decompression then cooling, culminating with development andalusite. Integration geochronological data set inferred trajectory suggests suprasolidus cooling must have been slow, order 2.5–4 °C Ma−1. addition, HTLP were generated within crust relatively normal thickness. Despite long duration over which occurred, there is no evidence for external magmatic inputs or associated long-lived extension. Instead, it seems probable metamorphism driven significant extent conductive heating provided high crustal heat production voluminous pre-metamorphic granitic rocks.