A multiscale approach to investigate hydraulic attributes of natural fracture networks into two tight sandstone fields, ahnet, algeria.

Regardless of the porosity of the matrix, fractures have a crucial role in increasing permeability. In this article, the critical role that natural fractures may play in enhancing fluid flow characteristics is considered. An attempt to demonstrate the contribution of fractures on enhancing the permeability was done, assuming the genetic relationship between complex fracture systems at different scales. A statistical approach aims to compare hydraulic properties of two tight sandstone fields in a Cambro Ordovician reservoir situated in the Ahnet Basin, Algeria, using a multiscale approach. The first field, situated in the Eastern region, denotes smaller fractures with three different orientations. In comparison, the second field, located in Western domain, is dominated by long faults, oriented N-S. However, the most predominant direction is NW-SE. In the first part, the connectivity of the networks was analyzed, and the results were plotted in a ternary diagram showing that the first field is characterized by a strong connectivity, probably due to the higher intensity of faults. Then, the dilation and shear tendency were displayed based on the current stress of the field. The outputs showed that fractures in the first field have a dilation and slip tendency higher which means that they are probably open and can participate in the creation of a fluid flow path. This is probably due to their orientation, parallel to the maximum horizontal stress. In the second part of this paper, naturally open fractures at the borehole scale were investigated and then compared to the seismic scale. Finally, the matching of the results at the two scales was studied