Abstract: Systems and methods for activating a down hole tool in a wellbore. A trigger is moveably positioned in the interior of a base pipe and includes a first end and a second, smaller end. The trigger is moveable between an unactivated position where a port in the base pipe is blocked and an activated position where the port is open. At least one latch member prevents movement of the trigger from the unactivated position to the activated position until a predetermined force is applied to the trigger. Increasing pressure in the interior increases a force differential between the first end and the second end. When the force differential is substantially equal to the predetermined force, the latch releases and allows the trigger to move from the unactivated position to the activated position, thereby opening the port to permit activation of the down hole tool.

Abstract: A method of installing a wellbore junction assembly in a well can include connecting at least two tubular strings to one opposite end of a tubular string connector with similarly dimensioned oriented connections, whereby the tubular strings are interchangeably connectable to the connector by the oriented connections. A wellbore junction assembly can include at least two tubular strings and a tubular string connector having opposite ends. Each of the tubular strings may be secured to one opposite end of the connector by oriented connections, whereby each of the tubular strings has a fixed rotational orientation relative to the connector. A well system can include a tubular string connector, each of first and second tubular strings being secured to the connector, and a support which reduces bending of the second tubular string which results from deflection of the second tubular string from one wellbore section into another wellbore section.

Abstract: An oxygen scavenger for completion brines effective and stable in high temperature subterranean formations. In one embodiment, the scavenger contains erythorbate and alkylhydroxlyamine.

Abstract: A release assembly (200) for releasing a portion of a tool string in a wellbore. The release assembly (200) includes an outer housing (202) having a fishing receptacle (206) disposed therein. The fishing receptacle (206) includes a fishing neck (208). A support assembly (214) is disposed within the housing (202). The support assembly (214) has a first position wherein the support assembly (214) engages the fishing neck (208) to prevent separation of the fishing receptacle (206) from the housing (202) and a second position wherein the support assembly (214) is disengaged from the fishing neck (208) no longer preventing separation of the fishing receptacle (206) from the housing (202). An actuator (224), disposed within the housing (202), maintains the support assembly (214) in the first position until actuation thereof allows the support assembly (214) to shift to the second position.

Abstract: A release assembly (200) for releasing a portion of a tool string in a wellbore. The release assembly (200) includes an outer housing (202) having a fishing receptacle (206) disposed therein. The fishing receptacle (206) includes a fishing neck (208). A support assembly (214) is disposed within the housing (202). The support assembly (214) has a first position wherein the support assembly (214) engages the fishing neck (208) to prevent separation of the fishing receptacle (206) from the housing (202) and a second position wherein the support assembly (214) is disengaged from the fishing neck (208) no longer preventing separation of the fishing receptacle (206) from the housing (202). An actuator (224), disposed within the housing (202), maintains the support assembly (214) in the first position until actuation thereof allows the support assembly (214) to shift to the second position.

Abstract: An inhibitive water-based polymer mud system and method for using the system in drilling and in stabilizing wellbores is disclosed for use in water sensitive formations as an alternative to oil-based muds or water-based muds comprising ferro-chrome lignosulfonates. The system comprises a fresh water or salt water base thinned or dispersed with a sulfonated acrylic copolymer having a hybrid/graft lignosulfonate multipolymer structure containing carboxylate and sulfonate functional groups with synthetic polymer side chains covalently linked to a base lignosulfonate material, having a molecular weight in the range of about 1,000 to about 15,000, and having a high anionic charge density. This system is effective and has stable rheology over a broad pH range, even at a near neutral pH of 8.0. The drilling fluids do not contain heavy metals and are rheologically tolerant to contaminants such as cement, anhydrite and sodium and temperatures as high as about 400° F.

Abstract: A downhole actuation system comprises an actuation mechanism comprising an indicator; a wellbore tubular; and a collet coupled to the wellbore tubular. The collet comprises a collet protrusion disposed on one or more collet springs, and the collet protrusion has a position on the one or more collet springs that is configured to provide a first longitudinal force to the indicator in a first direction and a second longitudinal force to the indicator in a second direction. The first longitudinal force is different than the second longitudinal force.

Abstract: A downhole packer assembly for steam injection and casing pressure testing. The downhole packer assembly includes a housing assembly having intake and discharge ports. A seal assembly is positioned around the housing assembly between the intake and discharge ports and is operable to provide a fluid seal with a casing string. A mandrel is positioned within the housing assembly forming a micro annulus therewith and providing an internal pathway for fluid production therethrough. A valve assembly is disposed between the housing assembly and the mandrel and is operable between closed and open positions by a piston assembly such that the intake and discharge ports and the micro annulus provide a bypass passageway for steam injection around the seal assembly when the valve assembly is open and the seal assembly provides a downhole surface for pressure testing of the casing string uphole thereof when the valve assembly is closed.

Abstract: A method of drilling a wellbore can include drilling the wellbore with a continuous tubing drill string, and sensing at least one parameter with an optical waveguide in the drill string. A well system can include a continuous tubing drill string, and an optical waveguide in the drill string. The optical waveguide may sense at least one parameter distributed along the drill string.

Abstract: Disclosed are spacer fluids comprising cement kiln dust (“CKD”) and methods of use in subterranean formations.

Abstract: A method of mitigating formation of an undesired accumulation of a substance in a well tool through which a well fluid flows can include heating a surrounding wall of an interior flow passage through which the well fluid flows. A system for of mitigating formation of an undesired accumulation of a substance in a well tool can include an interior flow passage having a surrounding wall, and a heater which heats the wall of the flow passage. Another method of mitigating formation of an undesired accumulation of a substance in a well tool can include monitoring the accumulation of the substance in the well tool, and heating a surrounding wall of an interior flow passage in response to detecting the accumulation.

Abstract: A method of mitigating perforating effects produced by well perforating can include causing a shock model to predict perforating effects for a proposed perforating string, optimizing a compliance curve of at least one proposed coupler, thereby mitigating the perforating effects for the proposed perforating string, and providing at least one actual coupler having substantially the same compliance curve as the proposed coupler. A well system can comprise a perforating string including at least one perforating gun and multiple couplers, each of the couplers having a compliance curve, and at least two of the compliance curves being different from each other. A method of mitigating perforating effects produced by well perforating can include interconnecting multiple couplers spaced apart in a perforating string, each of the couplers having a compliance curve, and selecting the compliance curves based on predictions by a shock model of shock generated by the perforating string.

Abstract: An embodiment of the present invention comprises a method of treating a subterranean formation comprising: providing a treatment fluid comprising a kiln dust, biowaste ash, and water; and introducing the treatment fluid into a subterranean formation. Another embodiment of the present invention comprises a method of cementing comprising: introducing a cement composition into a subterranean formation, wherein the cement composition comprises a kiln dust, biowaste ash, and water; and allowing the cement composition to set in the subterranean formation. Yet another embodiment of the present invention comprises a method comprising: providing a spacer fluid comprising biowaste ash and water; introducing the spacer fluid into a well bore to displace at least a portion of a first fluid from the well bore; and introducing a cement composition into the well bore, wherein the spacer fluid separates the cement composition and the first fluid.

Abstract: A drill bit of the type used to drill a wellbore in the earth can comprise a bore formed in the drill bit, and a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between sections of the bore in the drill bit. The plug can comprise a spherically-shaped member. The plug can comprise a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in the different sections of the bore on respective opposite sides of the plug is substantially equalized.

Abstract: Various compositions are provided herein that include a composition that includes a well bore treatment fluid and a magnetically-sensitive component that includes a subterranean fluid additive. In some instances, the magnetically-sensitive component may be a ferrogel. In some instances, the ferrogel may include a polymer matrix and a magnetic species.

Abstract: A method of cementing in a subterranean formation comprising the steps of: (A) introducing a cement composition into the subterranean formation, the cement composition comprising: (i) cement; (ii) water; and (iii) a high-density additive selected from the group consisting of silicon carbide, sintered bauxite, and any combination thereof, wherein the cement composition has a density of at least 16 pounds per gallon; and (B) allowing the cement composition to set. According to an embodiment, the high-density additive is in a concentration of at least 30% by weight of the cement. A cement composition for use in an oil or gas well comprises: (A) cement; (B) water; and (C) a high-density additive selected from the group consisting of silicon carbide, sintered bauxite, and a combination thereof, wherein the high-density additive is in a concentration of at least 30% by weight of the cement, and wherein the cement composition has a density of at least 16 pounds per gallon.

Abstract: Selective placement of conformance treatments in multi-zone well completions. A method includes injecting a relative permeability modifier into a zone and optimizing a ratio of desired fluid to undesired fluid produced from the zone, including adjusting at least one flow control device between fully open and fully closed configurations. Another method includes injecting a relative permeability modifier into multiple zones, one at a time, via respective flow control devices, and then producing fluid from each of the zones. Another method includes identifying which of the zones to treat by, for each of the zones: a) closing flow control devices corresponding to the other zones, and b) evaluating fluid produced from the zone; and injecting a conformance treatment into the zones identified as the zones to treat.

Abstract: A well drilling system can include a hydraulics model which determines a modeled fluid friction pressure and a calibration factor applied to the modeled friction pressure, and a flow control device which is automatically controlled in response to a change in the calibration factor. A well drilling method can include drilling a wellbore, a fluid circulating through the wellbore during the drilling, determining a calibration factor which is applied to a modeled fluid friction pressure, and controlling the drilling based at least in part on a change in the calibration factor.

Abstract: A system can include multiple explosive assemblies, each assembly comprising an outer housing, an explosive component rotatable relative to the housing, and a selective firing module which causes detonation of the component in response to a predetermined signal. A method can include assembling multiple explosive assemblies at a location remote from a well, installing a selective firing module, an electrical detonator and an explosive component in a connector, and connecting the connector to an outer housing, and then transporting the assemblies from the remote location to the well. A well perforating method can include assembling multiple perforating guns, each gun comprising a gun body, a perforating charge, and a selective firing module which causes detonation of the charge in response to a predetermined signal. The guns are installed in a wellbore, with the charge of each gun rotating relative to the respective gun body.

Abstract: A drill bit can include a seal which seals against a drill bit surface, the seal including a matrix seal material and a plurality of hollow spheres in the matrix seal material. Another drill bit can include a seal with a matrix seal material, spheres being more dense in a portion of the matrix seal material as compared to in the matrix seal material outside of the portion, and the portion of the matrix seal material being in dynamic sealing contact with a drill bit surface during operation. A drill bit can include a seal between a cone and a journal, the seal comprising a matrix seal material and a plurality of spheres in the matrix seal material, the matrix seal material comprising nitrile.