Abstract: Various embodiments of methods and apparatus for detecting a change in an orientation of a portion of a structure. In some embodiments, the apparatus includes a processor, an energy storage unit, a location reporting unit, a wireless communication module and one or more inclination sensors. In some embodiments, each of the one or more inclination sensors is configured to measure inclination by measuring an orientation of the each of the one or more inclination sensors relative to a gravitational acceleration vector.

Abstract: By removing material of low permeability from within and around a perforation tunnel and creating at least one fracture at the tip of a perforation tunnel, injection parameters and effects such as outflow rate and, in the case of multiple perforation tunnels benefiting from such cleanup, distribution of injected fluids along a wellbore are enhanced. Following detonation of a charge carrier, a second explosive event is triggered within a freshly made tunnel, thereby substantially eliminating a crushed zone and improving the geometry and quality (and length) of the tunnel. In addition, this action creates substantially debris-free tunnels and relieves the residual stress cage, resulting in perforation tunnels that are highly conducive to injection under fracturing conditions for disposal and stimulation purposes, and that promote even coverage of injected fluids across the perforated interval.