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Diffusion & Pressure solution slides. Pressure solution (diffusion flow) in sandstone…. Pressure solution (diffusion flow) in sandstone…. Pressure Solution: cleavage (~ horizontal) cutting lithological layering. Image from Greg Davis’ structure resources DVD.
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Pressure Solution: cleavage (~ horizontal) cutting lithological layering
Stylolites: seams of insoluble material left behind at localized sites of pressure solution Image from Greg Davis’ structure resources DVD
At high T, crenulation cleavage develops in slates & schists by pressure solution Image from Greg Davis’ structure resources DVD
Accretionary complexes show volume losses of 30-40% by p.s. at low stresses and temperatures of 200-400°C 1 1e.g. Ring et al, 2001; Schwarz and Stockhert, 1996
Pressure solution cleavage (top R to bottom middle) cutting horizontal bedding in a sandstone
Undeformed Black Hills Sandstone (BHQ), cross polars ~50 microns
BHQ (fast strain rate, 10^-4 /s), note strong lattice distortion, tiny rxl grains ~50 microns
BHQ, Low strain rate (10^-6), power law flow, note large rxl grains, subgrains ~50 microns
BHQ, same sample, gypsum plate inserted, color dominance indicates LPO ~50 microns
BHQ, undeformed, cross polars, gypsum plate inserted (No LPO) ~200 microns
BHQ (fast strain rate, 10^-4 /s), note strong lattice distortion, tiny rxl grains ~50 microns
BHQ, very low strain rate overprint of high strain rate fabric (strain energy now low) ~50 microns