Abstract: A method of fracturing subterranean formations wherein a formation is fractured and propped two or more times to increase the width of the propped fracture.

Abstract: An improved sucker rod pumping system for an oil well includes a valve member mounted in the rod string, a valve seat formed in the wellhead, and means for moving the rod string upwardly to cause the valve member to sealingly engage the valve seat. The valve member is located on the rod string such that during normal pumping operation, it will not contact the valve seat or otherwise interfere with the pumping operations. When it is desired to close in the well or inject a fluid therein, the rod string is elevated above its normal stroke until the valve member sealingly engages the valve seat.

Abstract: A hydraulic fracturing method wherein a viscous oil-in-water emulsion is injected into a formation under sufficient pressure to fracture the formation. The emulsion contains from about 70 to about 90 volume percent of an internal liquid hydrocarbon phase, from about 10 to about 30 volume percent of an external aqueous phase and sufficient amounts of a nonionic surfactant to stabilize and viscosify the emulsion. The preferred hydrocarbon phase concentration is between about 75 and 85 volume percent. The nonionic surfactant also gives the emulsion a breaking temperature which is not greater than the temperature of the formation. Preferably, an electrolyte is used to adjust the temperature at which the emulsion will break. After fracturing is completed the emulsion is then left in the wellbore for a sufficient time to permit the temperature of the emulsion to reach its breaking temperature. Upon breaking, the emulsion reverts to a low viscosity fluid which is readily removable from the formation.

Abstract: A method of consolidating incompetent subterranean formation surrounding a well wherein a liquid resin diluted with a two-part diluent is injected into the formation and is followed by an overflush liquid to extract the diluent but leave the resin on the sand grains. The two-part diluent comprises a first component miscible with the resin and a second component immiscible with the resin but miscible with the first component and the overflush liquid.

Abstract: A three-phase separator for processing produced fluids from an oil well is divided into an emulsion, an oil, and water compartments. The separator includes a water weir and controls for automatically adjusting the position of the water weir to maintain the oil-emulsion interface in the emulsion compartment substantially constant.