Anion diffusion in clay-rich sedimentary rocks – A pore network modelling

A Discussion on the Origin of Clay Minerals in Sedimentary Rocks

X-ray analyses of the clay minerals from thousands of sediments indicate that any of the major clay minerals can occur in abundance in any of the major depositional environments and there is no consistent coincidence between specific clay minerals and specific depositional environments. It is concluded that the great majority of clay minerals in sedimentary rocks are detrital in origin, strongl...

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 ...

A Growth Model for Porous Sedimentary Rocks

A growth model for porous sedimentary rocks is proposed, using a simple computer simulation algorithm. We generate the structure by ballistic deposition of particles with a bimodal size distribution. Porosity and specific surface area are calculated varying the proportion of small and larger particles. Permeability and it’s variation with porosity are studied. The fractal nature of the pore spa...

Time-dependent Diffusion Coefficients in Sedimentary Rocks Predicted by a Fractal Capillary Model

Applying the pulsed field-gradient nuclear magnetic resonance (PFG-NMR) technique, timedependent self-diffusion coefficients, ) (∆ D 0 D , of water were measured in anhydrite cemented sandstones, in order to determine geometrical parameters of the pore space. As a first approach the Padé approximation, combining the short-time behaviour with the long-time asymptotic value of (where is the bulk ...

Groundwater in Sedimentary, Metamorphic and Volcanic Rocks