Abstract: A method for monitoring hydrocarbon and water production from different production zones/sections in a hydrocarbon reservoir and/or injection wells and detection of different phenomena such as e.g. local variations in pH, salinity, hydrocarbon composition, temperature, pressure, microorganisms, and the difference between production of formation and/or injection water from various zones/sections. The method includes dividing regions around wells in the reservoir into a number of zones/sections, and injecting or placing specific tracers with unique characteristics for each zone/section into the formation in these regions such that tracers are placed as integrated parts of the well completion or placed and immobilized in these regions through injection, squeeze or by other techniques. The tracers can also be immobilized or placed on a filter, a casing or other constructions surrounding the well in each zone/section. The tracers are specific or introduced to give specific information from each zone/section.

Abstract: Compositions and methods for determining the source of treatment fluids being produced from a production formation having multiple zones.

Abstract: Compositions and methods for tracking the transport of particulate solids during the production of hydrocarbons from a subterranean formation.

Abstract: A method is described for inhibiting migration of fluids into and/or out of a treatment area undergoing an in situ conversion process. Barriers in the formation proximate a treatment area may be used to inhibit migration of fluids. Inhibition of migration of fluids may occur before, during, and/or after an in situ treatment process. For example, migration of fluids may be inhibited while heat is provided from heaters to at least a portion of the treatment area. Barriers may include naturally occurring portions (e.g., overburden, and/or underburden) and/or installed portions.

Abstract: A tracer release method for monitoring fluid flow in a well utilizes a deformable container comprising a liquid tracer material which container has an outlet which debouches into the neck portion of a venturi in a well conduit. The container has a wall which is at least partly exposed to the fluid pressure at the relatively wide in- or outlet of the venturi, so that an amount of tracer is injected continuously or discontinuously into the well effluents which is proportional to the pressure difference p across the venturi, which pressure difference p is indicative of the fluid density &rgr; and squared fluid velocity &ugr;.

Abstract: Tracing hydraulic fractures, stimulations, selective cement jobs, etc. in oil and gas wells includes introducing into a well in a zone of interest a plurality of radio frequency transmitting elements each having an identification, moving in the well a reader tool operative for transmitting radio waves so as to generate and send a radio frequency signal for activating the radio frequency transmitting elements and thereafter to receive a signal returned from the corresponding radio frequency transmitting elements together with the identification of each radio frequency transmitting element, and analyzing data related to the sending of the radio frequency signal from the reader tool to the radio frequency transmitting element and the receiving of the radio frequency signal from the radio frequency transmitting elements with the identification of the radio frequency transmitting elements, so as to trace a corresponding hydraulic fracture, stimulation, selective cement job, etc., in the zone of interest.

Abstract: A method and apparatus detects the presence of a fluorescent tracer dye, a change in capacitance, or a change in fiber optic electrical properties to determine whether or not a TCP gun has fired. The method and apparatus detects the number of charges fired to determine whether or not all TCP guns have fired and also determines the contributions of injection wells to producing wells by introducing fluorescent tracers into injection wells and detecting the presence of the fluorescent tracers at production wells. The invention places fluorescent dye particles in a gravel pack to sense when a gravel pack is deteriorating by detecting the tracer dye particles in the well flow.

Abstract: A petroleum well (20) comprises a well casing (30), a production tubing (40), a source of time-varying current (68), a downhole tracer injection device (60), and a downhole induction choke (90). The casing (30) extends within a wellbore of the well (20). The tubing (40) extends within the casing (30). The current source (68) is located at the surface. The current source (68) is electrically connected to, and adapted to output a time-varying current into, the tubing (40) and/or the casing (30), which act as electrical conductors for providing downhole power and/or communications to the injection device (60). The injection device (60) comprises a communications and control module (80), a tracer material reservoir (82), and an electrically controllable tracer injector (84). The communications and control module (80) is electrically connected to the tubing (40) and/or the casing (30). The downhole induction choke (90) is located about a portion of the tubing (40) and/or the casing (30).

Abstract: Disclosed is a method of determining the extent of recovery of materials injected into a oil well comprising the steps of: a) preparing a material to be injected into an oil well; b) admixing therewith a chemical tracer compound at a predetermined concentration; c) injecting the admixture into an oil well; d) recovering from the oil well a production fluid; e) analyzing the production fluid for the concentration of the chemical tracer present in the production fluid; and f) calculating the amount of admixture recovered from the oil well using the concentration of the chemical tracer present in the production fluid as a basis for the calculation. Fluorinated benzoic acids are disclosed as a preferred tracer.

Abstract: Methods and apparatus are provided which permit well testing operations to be performed downhole in a subterranean well. In various described methods, fluids flowed from a formation during a test may be disposed of downhole by injecting the fluids into the formation from which they were produced, or by injecting the fluids into another formation. In several of the embodiments of the invention, apparatus utilized in the methods permit convenient retrieval of samples of the formation fluids and provide enhanced data acquisition for monitoring of the test and for evaluation of the formation fluids.

Abstract: Methods are disclosed for hydraulic fracturing of subterranean reservoir formations using various combinations of gelled fluid, nitrogen, and carbon dioxide base components, in association with proppant and other additives. Selected base components are pumped down a wellbore tubing while other selected base components are simultaneously pumped down the wellbore tubing-casing annulus for downhole mixing into a composite fracturing fluid in the downhole region of the wellbore proximal to the reservoir objective. Thereby, changes may be timely effected in the composite fluid composition and fluid properties, substantially immediately prior to the composite fluid entering the formation. Such real-time modifications may be effected to readily preempt screenout occurrences and may facilitate composite fluid compositions which otherwise are frequently undesirable to pump from the surface. Such composite fluid combinations include components phases of each of carbon dioxide, nitrogen and a base fluid.

Abstract: A method and apparatus for determining whether a tubing conveyed perforating (TCP) gun has fired by detecting a change in characteristics of the flow of an oil well. A method and apparatus detects the presence of fluorescent tracer dye to determine whether or not a TCP gun has fired. The method and apparatus detects a change is capacitance, or fiber optic electrical properties to determine whether or not a TCP gun has fired. The method and apparatus detects the number of charges fired to determine whether or not all TCP guns have fired and also provides a method and apparatus for determining the contributions of injection wells to producing wells by introducing fluorescent tracers into injection wells and detecting the presence of the fluorescent tracers at production wells. A method and apparatus is provided for placing fluorescent dye particles in a gravel pack to sense when a gravel pack is deteriorating by detecting the tracer dye particles in the well flow.

Abstract: An induction choke in a petroleum well where a voltage potential is developed across the choke to power and communicate with devices and sensors in the well. Preferably, the induction choke is a ferromagnetic material and acts as an impedance to a time-varying current, e.g. AC. The petroleum well includes a cased wellbore having a tubing string positioned within and longitudinally extending within the casing. A controllable gas lift valve, sensor, or other device is coupled to the tubing. The valve sensor, or other device is powered and controlled from the surface. Communication signals and power are sent from the surface using the tubing, casing, or liner as the conductor with a casing or earth ground. For example, AC current is directed down a casing or tubing or a lateral where the current encounters a choke. The voltage potential developed across the choke is used to power electronic devices and sensors near the choke.

Abstract: A method for locating a drill bit when drilling out cementing equipment from a casing of a wellbore. A first step involves placing in the casing of the wellbore at the time of placing cementing equipment, at least one coloured marker member. A second step involves monitoring cuttings during drilling for traces of colour. Penetration of a drill bit into the cementing equipment is indicated by coloured cuttings from the at least one coloured marker member.