Abstract: Hydrocarbon base drilling fluids which are selectively convertible to cementitious compositions that set into hard substantially impermeable masses and methods of using such drilling fluids are provided. The drilling fluids are basically comprised of a hydrocarbon liquid having particulate hydraulic cement suspended therein. The drilling fluids are converted to cementitious compositions by admixing water and a surfactant therewith.

Abstract: The addition of an adhesive coated material in intimate mixture with particulates for fracturing, gravel packing or other formation treatments decreases or substantially eliminates the flowback of particulates whether proppants or formation fines while stabilizing the particulate within the formation. Preferred adhesive coated materials include glass or ceramic fibers, polyolefins, polyamides, polyvinyls and cellulose derivatives in the form of particles, ribbons, fibers or flakes.

Abstract: In a Measurement-While-Drilling system, selecting the fixed frequency in a pulse signal generator utilizes constructive interference to enhance the signal level in an amplitude modulated signal. The pulse generation system preferably includes a plurality of mud sirens in tandem to further enhance signal level and to provide multiple amplitude levels to increase data transmission rate.

Abstract: A concentric wet connector system useful for connecting, disconnecting and reconnecting small diameter fluid lines (40, 42, 44) and electrical lines (46) downhole in oil and gas wells, the system comprising first and second slidably engageable well tubulars (32, 38) coaxially disposed around a longitudinal bore, each well tubular having a circumferentially extending wall section containing at least one auxiliary conduit leading to a connector port 64 paired and communicating with a connector port 66 of the other tubular. The connector ports in each well tubular are preferably spaced apart both circumferentially and longitudinally.

Abstract: A method is disclosed for determining the thickness of cement that has been placed in an annulus between a casing string and a wellbore penetrating a formation, wherein the method includes the steps of: logging the amount of radioactivity emitted by a radioactive material in the formation prior to emplacement of the casing and cement, including in the cement an amount of the radioactive material, placing the casing and cement in the wellbore, logging the amount of radioactivity emitted by the radioactive material and transmitted through the casing and calculating the amount of cement in the annulus by determining the amount of the radioactive material in the annulus.

Abstract: Method of admixing and placing a substantially non-flowable cementitious material into an underground space, such as a mine shaft or the like. In a preferred embodiment, a cement slurry including about 95% Class F fly ash and about 5% hydraulic cement is admixed with an activator using a high intensity mixer to form a substantially non-flowable cementitious material, wherein the substantially non-flowable material is pumped through a conduit and placed into the underground space. The cementitious material does not flow away from the area of placement.

Abstract: The invention discloses a method of effecting fracturing in a subterranean formation utilizing substantially constant density fluids whereby proppant segregation is minimized or eliminated within the formation. Fluid density is adjusted by varying the salt content or addition of a gas or gasifiable liquid or both as proppant is added to the treatment fluid.

Abstract: A downhole chemical cutting tool for cutting downhole tubular goods and supporting the tubular goods within the well through a load bearing hub section in the tool. The tool comprises an elongated tool body having a upper head section which is adapted to be connected to a running string such as a string of coiled tubing capable of supporting large loads. The tool body comprises a propellent section and a cutting section. A chemical section is interposed between the propellant section and the cutting section and contains at least one chamber adapted to contain a chemical cutting agent. The cutting section is adapted to receive the chemical cutting agent and has an outer wall section which contains a plurality of transverse cutting ports arranged circumferentially of the cutting section.

Abstract: The present invention provides well cementing methods and compositions for use in cold environments which are particularly suitable for cementing conductor strings in deep water offshore wells. The cement compositions are basically comprised of a relatively coarse particulate hydraulic cement mixed with an ultra fine particulate hydraulic cement, sufficient water to form a pumpable slurry and a fluid loss control additive.

Abstract: Methods are provided for detecting the surface and/or subterranean locations of well treating fluids after the treating fluids have been introduced into wells and used for performing treatments therein. The methods of determining the subterranean locations of treating fluids basically comprise introducing a treating fluid into a well having a non-hazardous thermal neutron absorbing material combined therewith and performing a treatment in the well with the fluid. Fast neutrons from a source thereof are emitted in the well after the treatment whereby they interact with elements in the well and are thermalized. The thermal neutrons backscattered in the well are detected, and a count representing the detected thermal neutrons is generated. The subterranean locations of the treating fluid are determined by comparing the thermal neutron counts in the well before and after placement of the thermal neutron absorbing treating fluid therein.

Abstract: A continuous multi-component slurrying process at an oil or gas well comprises flowing at least three separate streams of different essential materials directly into a predetermined mixing unit at the oil or gas well, wherein each of the essential materials is required to obtain a predetermined defining characteristic of the slurry.

Abstract: The present invention provides improved cementitious compositions which can include drilling fluid as a component thereof and methods of cementing wells utilizing such compositions. The compositions are basically comprised of a cementitious material, water, a hardenable resinous material and optionally, drilling fluid in an amount up to about 70% by volume of the cementitious material in the composition.

Abstract: An aqueous foamed fracturing fluid composition and method for using the foamed fracturing fluid for fracturing subterranean formations that have been penetrated by a wellbore wherein the foamed fracturing fluid comprises: (a) a viscosifier which is preferably either hydrophobically modified guar or hydrophobically modified hydroxymethylcellulose; (b) a surfactant which is preferably alpha olefin sulfonate; and (c) the gas phase includes either nitrogen or carbon dioxide.

Abstract: A decentralizer for a diverter, a centralizing guide bushing and a downhole-deployable locating and orienting subsystem.

Abstract: A method and apparatus for use in setting sidetrack plugs in a well bore. The apparatus comprises an inflation packer assembly which may be attached to the lower end of the tubing string. The packer is inflated to seal against the well bore at the lower end of the sidetrack plug. The inflation packer is attached to a tubing string with a length of tail pipe. The tail pipe is releasably attached to the tubing string. After the inflation packer is sealed against the well bore, a cementitious fluid is circulated above the bladder to form the sidetrack plug. The tailpipe is then released and the tail pipe and the inflation packer remain in the hole and form a part of the sidetrack plug. An additional embodiment includes a whipstock connected to the inflation packer assembly.

Abstract: A drill stem diverter tool for removing gelled drilling fluid and filter cake from the side of a well bore. The apparatus comprises a housing adapted to be connected into a drill string. The housing includes a plurality of diverter ports which communicate a central opening of the housing with a well annulus. A valve means which can be moved from a first position which blocks the diverter ports to a second position which opens the diverter ports is disposed in the central opening. The diverter ports are angled and offset from the center line of the housing so that the fluid exiting the ports creates a turbulent circular motion. A stop is provided to limit the movement of the valve means. The valve means may also be moved from its second position back to its first position to block communication to the well annulus through the diverter ports.

Abstract: A well control valve assembly prevents flow from or to completion segments further downhole from the well control valve assembly once the stimulation stimulation/shifter string has been removed from the production tubing string. The well control valve assembly features a shaped flapper plate which, when opened, conforms closely to the shape and size of the production tubing string's interior diameter. The flapper plate is biased toward a closed position by a compression spring arrangement that includes an arm which levers the plate upward toward a seating surface. The valve assembly's closure is mechanically induced and is not responsive to a sensed well condition.

Abstract: Improved methods and systems for creating a multilateral well and improved multilateral well structures.

Abstract: A well logging apparatus is disclosed having an elongate body supporting a plurality of antenna coils housed in recesses formed on the body. A sleeve covers the segment of the body containing the antenna recesses and seals the antennas from borehole fluids. Electronics compartments formed in the body for housing signal conditioning circuitry are likewise sealed by the sleeve. The sleeve includes slotted regions filled with a sealant, the slotted regions being disposed about the antenna coils and providing an electromagnetically transparent window through the sleeve.

Abstract: A method of fracturing high permeability formations is provided utilizing a first crosslinked gel fluid to initiate the fracture followed by a second gel which results in improved proppant transport and packing of the fracture.