Pattern formation in sedimentary rocks: Connectivity, permeability, and spatial correlations

Pattern formation in sedimentary rocks: Connectivity, permeability, and spatial correlations

Sedimentary rocks have complicated permeability patterns arising from the geological processes that formed them. We concentrate on pattern formation in one particular geological process, avalanches (grain flow) in wind-blown or fluvial sands. We present a simple experiment and numerical model of how these avalanches cause segregation in particle size that lead to characteristic laminated patter...

Sedimentation and Sedimentary Rocks

Sedimentary rocks are one component of the modern threefold classification of rocks. They derive from the lithification of sediments, which are produced in basically two ways: by the mechanical deposition of grains derived from the alteration of other rocks (detrital or clastic rocks), or as chemical precipitates or grains formed organically or inorganically from an aqueous solution. The whole ...

Groundwater in Sedimentary, Metamorphic and Volcanic Rocks

Permeability and Relative Permeability in Rocks

Important features of the topology of the pore space of rocks can be usefully quantiied by analyzing digitized images of rock cross sections. One approach computes statistical correlation functions using modern image processing techniques. These correlation functions contain information about porosity, speciic surface area, tortuosity, formation factor, and elastic constants, as well as the uid...

Triple oxygen isotope variations in sedimentary rocks

Relatively large (P0.2&) O anomalies in the geologic record have been used to recognize atmospheric processes such as photochemical reactions and to trace changes in the partial pressures of O2 and CO2 in Earth’s atmosphere through time. However, recent oxygen isotope measurements of terrestrial rocks, minerals and waters also reveal common, smaller (but statistically significant) deviations fr...