Fractures and discontinuities

From the hydrogeological point of view, fractures and discontinuities are among the most important of geological structures. Most rocks possess fractures and other discontinuities (Figure 2.1) which facilitate storage and movement of fluids through them. On the other hand, some discontinuities, e.g. faults and dykes may also act as barriers to water flow. Porosity, permeability and groundwater flow characteristics of fractured rocks, particularly their quantitative aspects, are rather poorly understood. Main flow paths in fractured rocks are along joints, fractures, shear zones, faults and other discontinuities. There is a great need to understand hydraulic characteristics of such rocks, in view of (a) groundwater development to meet local needs, and (b) as depositories for nuclear and other toxic wastes.