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Showing 1 to 6 of 6 for “"crustal reworking"”.
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A low - δ 18 O intrusive breccia from the Koegel Fontein complex, South Africa
… the country rock during the Pan African when crustal reworking enabled deep circulation of surface water. This period of crustal reworking coincides with a 'Snowball Earth' event and would have been accompanied by 18 O - depleted meteoric water. In the Cretaceous, it is assumed that a mantle …
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Pan-African magmatism and regional tectonics of South Brazil
… all granitoids of the two belts have a strong crustal signature. The foliated granitoids of the Pelotas Batholith (600-550m.y.) are metaluminous, calkalkaline granodiorites, and have volcanic arc characteristics with Sr initial ratios between 0.708 and 0.710 and model ages in the range of …
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Petrogenesis of Mesoarchean high-K rocks in the Kaapvaal Craton: Investigating the Boesmanskop Alkaline Complex and Salisbury Kop batholith
… the presence of inherited zircon cores, and crustal isotopic signatures of the cumulus rocks suggest that they derive from magmas produced by low-degrees of fluid-absent anatexis of the lower crust (including recycled sediments). Phase equilibrium modeling conducted at pressure of 1.5 kbar …
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Metamorphic and crustal evolution of Australian-Antarctic Proterozoic margins
… study that characterises the metamorphic and crustal evolution of two key and understudied tectonic regions at opposing ends of the MAFWO. High thermal gradients at mid-crustal levels (6.0–6.5 kbar, 900 °C) prevailed in the east Musgrave Inlier, central Australia (east MAFWO), between ca. …
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Tectono-metamorphic history of the re-worked, high-grade Maud Belt at central-Eastern H.U. Sverdrupfjella, Antarctica
The reworking of granulites by amphibolite- to granulite-facies metamorphism can complicate the interpretation of their geological history because the event that reached higher peak P-T conditions will either completely overprint earlier peak assemblages or prevent the formation of new 'peak' …
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Evolution of continental crust in the Proterozoic : growth and reworking in orogenic systems
… between juvenile mantle derived extraction, infracrustal reworking and crustal recycling, needs to be estimated. Since the beginning of the century, the use of coupled in situ zircon U–Pb, Lu–Hf and O isotope analyses as a tool to address these questions have increased exponentially. Numerous …