Porosity microstructures of a sandstone affected by a normal fault

Abstract

Normal faults are part of the elements that control fluid flows in sedimentary basins. They can play the role of a barrier or a drain [Hippler, 1993]. These pathways are anisotropic. The aim of this study is to determine the fluid pathways and to characterise the pore network and its role in the transfer properties. Petrophysics, petrographics, geochemical and fluid inclusion studies allow us to characterise a Buntsandstein sandstone affected by a normal fault. This sandstone has a fluviatile origin, field evidenced by fluviatile channels, but also by some clay layers. The fault is located in the north east of France, in the Rhine Graben. The vertical displacement is about 3 meters, and the dip is 70o east. The fractured zone is composed of three compartments (the hanging wall and the footwall separated by a gouge) divided by three main faults (fig. 1). Oriented samples were taken from the three blocks and were studied following the procedure figure 2.