One or more subterranean zones are isolated from one or more other subterranean zones using a combination of solid tubulars and perforated tubulars.

A downhole packing mechanism for achieving sealed engagement with the bore of a well conduit comprises a mandrel positionable within a well by a tubing string. Surrounding the mandrel is a tubular body assemblage which is connectable to the mandrel for run-in purposes by a control dog and slot arrangement. An annular packing element surrounds the upper end of the tubular body assemblage and is compressed into sealing engagement with the well bore conduit by an upper slip assembly. A lower slip a...

A method of treating a subterranean well formation wherein a low pH highly viscous thixotropic treating fluid is introduced into the formation. The treating fluid is formed by combining an aqueous acid solution with an aqueous alkali metal silicate solution and a gelling agent whereby a highly viscous polymerized alkali metal silicate gel of low pH is produced followed by shearing of the gel to impart thixotropic properties thereto.

Gelled acidic compositions suitable for either matrix-acidizing or fracture-acidizing of subterranean formations, and methods of using said compositions in acidizing operations, are provided. Said compositions comprise water, a water-dispersible biopolysaccharide, an acid, a water-soluble compound of a polyvalent metal wherein the metal can be reduced to a lower polyvalent valence state and cause gelation of the water containing said biopolysaccharide and said acid, and a reducing agent capable ...

A subterranean plow blade for mounting onto a tractor in a clamping fashion for fast and easy mounting and removal. A blade holder is affixed to a tractor, and clamp pieces are pivotly mounted on the holder with one piece thereof engaging the blade and the other pieces forcing the first one piece tightly against the blade for holding same. The holding pieces are adjustably interrelated to accommodate variations in piece and blade sizes. The blade is arranged with a leading edge which penetrates ...

An expandable well screen has a desirable thin-wall construction together with a simplified fabrication method. In fabricating the screen, a flexible sheet of metal mesh filter media is diffusion bonded to an inner side of a perforated metal sheet which is then deformed to a tubular shape to form a filter structure having an outer perforated tubular shroud interiorly lined with the filter media. The tubular filter structure is telescoped onto a perforated base pipe and has its opposite ends seal...

A subterranean drain system that includes hollow dimples that extend perpendicularly from a drain board. The system also includes a connector that typically allows multiple boards to be connected together, or to connect to other elements.

Gelled acidic compositions suitable for either matrix-acidizing or fracture-acidizing of subterranean formations, and methods of using said compositions, are provided. Said compositions comprise water, a water-dispersible polymer of acrylamide, an acid, a water-soluble compound of a polyvalent metal wherein the metal can be reduced to a lower polyvalent valence state and cause gelation of the water containing said polymer and said acid, and a reducing agent capable of reducing said metal and cau...

A technique for stimulating production of fluids from a subterranean formation. The technique utilizes a tubular member disposed within a wellbore. The tubular member comprises transverse openings that facilitate a formation fracturing process. Subsequent to fracturing, a completion element may be deployed within the tubular element. In some applications, the completion element is an expandable element.

Gelled acidic compositions suitable for either matrix-acidizing or fracture-acidizing of subterranean formations, and methods of using said compositions in acidizing operation, are provided. Said compositions comprise water, a water-soluble cellulose ether, an acid, a water-soluble compound of a polyvalent metal wherein the metal can be reduced to a lower polyvalent valence state and cause gelation of the water containing said cellulose ether and said acid, and a reducing agent capable of reduci...