Abstract: Methods for locating fluid interfaces in a cased wellbore include generating vibrations in the casing, thereby forming oscillations in the wellbore fluids and the casing. The oscillations are detected by a vibration detector. The oscillations are recorded by a data acquisition system. Mathematical processing of the oscillations by cepstrum analysis is performed to determine the depths of interfaces between fluids in the annulus. The methods may also be employed to determine the time at which a cement slurry begins to set and harden. The methods may be performed in real time.

Abstract: A method for fracturing a subterranean formation, the method comprising injecting a fracturing fluid into a wellbore through the subterranean formation, thereby creating a fracture network in the subterranean formation, the fracturing fluid comprising a proppant and a plurality of polymer fibers having a deflection temperature ranging from about 70° C. to about 150° C. dispersed in a carrier fluid.

Abstract: A method of treatment of a subterranean formation penetrated by a wellbore, where the well has a plurality of previously stimulated intervals includes: a) pumping a viscous pill into a well with pressure curve registration by a wellhead pressure sensor; b) determining a depth (L) of treatment fluid entry point and depth uncertainties (L); c) generating a water hammer at the wellhead which excites tube waves; d) determining the depth (L) of the treatment fluid entry point and the depth uncertainties (L) by processing a water hammer by high frequency pressure monitoring method; e) determining a tube wave velocity from a combination of data from (b) to (d); f) performing a fracturing treatment; and g) generating a water hammer at the wellhead at the end of the fracturing treatment (f) with refined depth of treatment fluid entry point and with lower uncertainty.

Abstract: A method for fracturing a subterranean formation, the method comprising injecting a fracturing fluid into a wellbore through the subterranean formation, thereby creating a fracture network in the subterranean formation, the fracturing fluid comprising a proppant and a plurality of polymer fibers having a deflection temperature ranging from about 70° C. to about 150° C. dispersed in a carrier fluid.