Abstract: A method of predicting the failure of a rock formation surrounding a subterranean cavity, including a measuring set of parameters relating to pressure conditions and stresses in the rock formation surrounding the cavity; using the set of parameters to determine a rock strength; determining a first characteristic length relating to the size of the cavity; determining a second characteristic length relating to the grain size of the rock formation surrounding the cavity; using the first and second characteristic lengths to determine a correction for the rock strength; correcting said rock strength; and using a failure criterion and the corrected rock strength to predict a condition under which the rock formation is expected to produce debris. The results of the prediction can be used to monitor wellbore stability while drilling or optimize the production parameters for a hydrocarbon reservoir.

Abstract: A method and apparatus is described for increasing hydrocarbon production from a production well by determining a bedding plane (permeability anisotropy) of a hydrocarbon bearing formation and using a perforating tool to form in the formation holes having an essentially elliptical or elongated cross-section with the longest axis of said elliptical or elongated cross-section oriented perpendicular to said bedding plane (or in direction of the lowest permeability).

Abstract: The present Invention relates to novel devices and methods to minimize the production of sand in subterranean environments; in particular, in poorly consolidated formations, sand is often co-produced along with the desired fluid (e.g., oil); sand production is undesirable, hence in the present Invention, elliptically shaped perforations of a particular orientation are created in the casing (or directly into the formation in the case of an uncased wellbore) that lines wellbore drilled through the formation, to improve near-wellbore stability of the formation, hence minimizing sand intrusion.