Diagenesis and the effects of cataclastic deformation on the Permo-Triassic New Red Sandstone, Isle of Arran, Scotland

Diagenesis in the Permo-Triassic New Red Sandstone, Isle of Arran is characterized by early cementation hematite, clay, and calcite minerals, followed burial compaction, quartz, feldspar, pyrite cementation. Cataclasis post-dated quartz feldspar reduced grain pore aperture size deformed samples. Samples with cataclastic bands typically have 18% porosity 8.81 mD permeability on average. Whereas, undeformed samples an average 22% 381 mD. was not as important diagenesis controlling sandstone permeability. However, cataclasis resulted lower very poor to medium Cataclastic compartmentalize reservoir sands cause a high heterogeneity porous sandstones. Poikilotopic blocky cement postdates clay hematite cement. In addition, overgrowths also postdate hematite. poikilotopic fills framework grains that larger void volumes than grain/grain contacts where are present. fracturing overgrowths. Therefore, occurred after development Dissolution postdated formation authigenic from reduction. The distributions sizes against cumulative mercury studied shows level reduction for single-cataclastic multi-cataclastic bands. distribution apex illustrates effective band sample may be up > 2 times comparison thin single has only slightly volume host sample.