Does anyone know how the Hope Valley Alaskite Gneiss formed????
Hope Valley Alaskite Gneiss, light pink and gray medium and coarse grained granitic gneiss (Precambrian age) Mamacoke Formation, light and dark gray medium grained gneiss (Precambrian age) New London Gneiss; gray granitic gneiss (Precambrian age) Minerals of Interest Quartz, potassium feldspar and mica are found in the bedrock Layers of pink garnet sand may be found on the beach Interesting Geologic Features Cliffed headland Drumlin shaped hill Recessional moraine Spit beach Sand dunes Salt Marsh Lagoon/tidal estuary Field, petrographic, microstructural and isotopic studies of mylonitic gneisses and associated pegmatites along the Hope Valley shear zone in southern Rhode Island indicate that late Palaeozoic deformation (c. 275 Ma) in this zone occurred at very high temperatures (>650 °C). High-energy cuspate/lobate phase boundary microstructures, a predominance of equant to sub-equant grains with low internal lattice strain, and mixed phase distributions indicate that diffusion creep w
