Abstract: A system for use with a well having multiple zones can include multiple well screens which filter fluid flowing between a tubing string and respective ones of the zones, at least one optical waveguide which senses at least one property of the fluid as it flows between the tubing string and at least one of the zones, multiple flow control devices which variably restrict flow of the fluid through respective ones of the well screens, and multiple pressure sensors which sense pressure of the fluid which flows through respective ones of the well screens. A tubing string for use in a subterranean well can include at least one well screen, at least one flow control device which selectively prevents and permits substantially unrestricted flow through the well screen, and at least one other flow control device which is remotely operable, and which variably restricts flow through the well screen.

Abstract: Methods and apparatus to control the additives to a chemical composition for use in the oil field services industry. Specifically, a method and apparatus to determine fluid parameters for a fluid, including introducing an inert tracer in a component; forming a fluid comprising the component; observing the concentration of the tracer in the fluid; calculating the concentration of the component in the fluid; and introducing the fluid into a subterranean formation. An apparatus and method to control fluid parameters of interest for an oilfield formulation fluid such as chemical composition including introducing an inert tracer in a component; forming a fluid comprising the component; observing the concentration of the tracer in the fluid; calculating the concentration of the component in the fluid; adjusting a flow rate when forming the fluid in response to the calculating; and introducing the fluid into a subterranean formation.

Abstract: An electro-mechanical indicator system for signaling when a droppable object (such as, for example, a dart, plug or ball) is released during well cementing operations. A body section has first and second chambers divided by a fluid and pressure sealing barrier. A mechanical trigger mechanism is situated in the first chamber, which is exposed to elevated pressures and harsh wellbore fluids. Less robust components, such as sensor(s), power source(s), and signal device(s) located in the second chamber, remain isolated from the wellbore environment and elevated pressures.

Abstract: A method for correlating data predicted by a processor physics-based geologic model to describe a subsurface region with obtained data describing the subsurface region. Data is obtained describing an initial state of the subsurface region. Data describing a subsequent state of the subsurface region is predicted. The predicted data is compared with the obtained data taking into account whether the obtained data or the predicted data represent a discontinuous event. A sensitivity of the predicted data is determined if the predicted data is not within an acceptable range of the obtained data. The data describing the initial state of the subsurface region is adjusted based on the sensitivity before performing a subsequent iteration of predicting data describing the subsequent state of the subsurface region. A representation of the subsurface region based on the data describing the subsequent state of the subsurface region is outputted.

Abstract: A method of servicing a subterranean formation comprising providing a wellbore penetrating the subterranean formation and having a casing string disposed therein, the casing string comprising a plurality of points of entry, wherein each of the plurality of points of entry provides a route a fluid communication from the casing string to the subterranean formation, introducing a treatment fluid into the subterranean formation via a first flowpath, and diverting the treatment fluid from the first flowpath into the formation to a second flowpath into the formation.

Abstract: This disclosure relates to determining optimal parameters for a downhole operation. In a general aspect, a computer-implemented method for managing a downhole operation is described in this disclosure. The method includes receiving a continuous stream of real-time data associated with an ongoing downhole operation at a data ware house. In the meantime, a selection of a downhole parameter is received from a user. Then, with a computing system, the selected downhole parameter is optimized based on a portion of the received stream of data to approach a target value of the selected downhole parameter. The optimized downhole parameter can then be used in the ongoing operation.

Abstract: A method of correcting a downhole speed of a tool string moving in a wellbore. In some implementations, the method includes obtaining a downhole tool speed with an accelerometer, moving the tool string past at least two casing collars, calculating the average tool speed over the interval between collars, and comparing the downhole tool speed as calculated using the data from the accelerometer to the average tool speed calculated based on the time and the interval between the casing collars, determining a correction factor, and determining a corrected downhole tool speed. A system includes a casing collar locator, an accelerometer, and a processor adapted to compare the downhole tool speed calculated using data from the accelerometer to the average downhole tool speed calculated using the time and casing collar location, determine a correction factor and determine a corrected downhole tool speed.

Abstract: Techniques involve determining the conductivity profile of a formation from a well between a surface location and a borehole location. The method involves placing a first sensor at the surface location, a second sensor located at the borehole location, obtaining a first signal by detecting Schumann resonances from the electric field occurring at the first location, obtaining a second signal by detecting Schumann resonances from the electric field occurring at the second location with the second sensor; and combining the first and the second signal to determine the conductivity profile of the formation between the first location and the second location.

Abstract: Disclosed are systems and methods for positively identifying wellbore projectiles introduced downhole. One well system includes at least one wellbore projectile configured to be introduced into a flow path associated with a work string arranged within a wellbore and extending from a wellhead installation, at least one optical computing device in optical communication with the flow path and having at least one integrated computational element configured to detect a characteristic of the at least one wellbore projectile and generate a resulting output signal indicative of the characteristic of the at least one wellbore projectile, and a computational system configured to receive the resulting output signal and associate the resulting output signal with a size or configuration of the at least one wellbore projectile.

Abstract: A firing head actuator for a well perforating system. The firing head actuator includes a housing assembly with a first impact piston initially secured thereto and slidably disposed therein. An electronic time delay assembly, a trigger assembly and an initiator are also disposed within the housing assembly. A second impact piston is initially secured within and slidably disposed within the housing assembly. In operation, a pressure signal of a predetermined threshold actuates the first impact piston, the first impact piston mechanically actuates the electronic time delay assembly, after a predetermined time period, the electronic time delay assembly electrically actuates the trigger assembly, the trigger assembly mechanically releases the second impact piston and pressure shifts the second impact piston into contact with the initiator.

Abstract: The present invention relates to an annular barrier system (1) for proving a testable annular barrier arranged between a first metal casing (2) or borehole and a second metal casing (3), the second metal casing having an outer face. The annular barrier system comprises a first annular barrier (4) and a second annular barrier (5), each barrier comprising a tubular part (6) made of metal extending in a longitudinal direction for mounting as part of the second metal casing, an expandable metal sleeve (7) surrounding and connected with the tubular part and defining an annular barrier space (13), and a first fluid passage (11) in the tubular part for letting fluid into the annular barrier space to expand the sleeve.

Abstract: Disclosed are systems and methods for actively controlling the temperature of an integrated computational element used in an optical computing device in order to affect its performance. One method includes providing an integrated computational element configured detect a characteristic of a substance and provide a transmission profile via a detector corresponding to the characteristic, and controlling a temperature of the integrated computational element in order to maintain the transmission profile within an optimal operating range.

Abstract: A method includes introducing a treatment fluid including a first polymer gel into a subterranean formation to generate a production fluid having an aqueous portion and a hydrocarbon portion, treating the aqueous portion of the production fluid with chlorine dioxide to separate additional hydrocarbons from the aqueous portion, and adjusting the viscosity of the treated aqueous portion prior to introducing the treated aqueous portion back into the subterranean formation.

Abstract: The present invention is directed to methods and systems for obtaining log data on a cased wellbore concurrently with wellbore cleanout operations. In some such embodiments, a combination of at least one cleaning means and at least one logging tool are integrated or otherwise affixed to a common workstring, such that both wellbore cleanout and logging operations can be accomplished without having to remove the workstring from the well between such operations. In some such embodiments, the one or more logging tool(s) transmit information about the cased wellbore to the surface wirelessly. In some or other such embodiments, such information is transmitted via cable, in real-time or in batch mode. In some or still other such embodiments, such information is stored in memory and accessed subsequent to the workstring being extracted from the wellbore.

Abstract: The invention subject of this disclosure teaches a method of determining a production factor for a carbonaceous material reservoir, the method comprising: providing a well in a carbonaceous material reservoir; providing unsampled fluid at a depth in the well; placing a sensor adjacent to the unsampled fluid and performing a measurement on the unsampled fluid; using data from the measurement to determine a partial pressure of a solution gas in the carbonaceous material reservoir; and determining a production factor for the carbonaceous material reservoir from the partial pressure of the solution gas.

Abstract: A method for calculating a value representative of a downhole temperature in a hydrocarbon well, wherein the well includes production tubing inside an outer tubing, an annulus is provided between the production tubing and the outer tubing, and the annulus receives a hydraulic control line supplying hydraulic fluid for the control of a downhole device, the method including sensing the pressure of hydraulic fluid in the control line at the wellhead, and using a measurement of the pressure to calculate the value representative of the downhole temperature.

Abstract: Methods and apparatus are provided for measuring one or more parameters associated with an artificial lift system for hydrocarbon production and operating the system based on the measured parameters. One embodiment of the invention provides a lubricator for a plunger lift system, which generally includes a housing, a spring disposed in the housing for absorbing an impact by a plunger, and a sensor configured to measure at least one parameter of the spring. One example method of operating a plunger lift system for hydrocarbon production generally includes measuring at least one parameter of a spring disposed in a lubricator of the plunger lift system and operating the plunger lift system based on the measured parameter.

Abstract: Apparatus and method are provided to restore contaminated groundwater based on in-situ periodic pumping and recharging. The apparatus includes a contaminated groundwater suction system, an in-situ restoration system, and a reinjection system. The suction system includes a suction well and a suction pipeline. The suction system is connected with the in-situ restoration system. The in-situ restoration system is connected with the reinjection system. The reinjection system includes a reinjection pipeline and a reinjection well. Prior to the in-situ restoration, a pumping test for suction well and an injection test for reinjection well are conducted. Through reinjecting the processed contaminated groundwater, this approach is capable of diluting contaminated water layer, reducing the pollutant concentration in the target aquifer, providing convenience for the subsequent processing, and cutting the cost.

Abstract: A drill for excavating a bore in the earth includes a steerable boring tool configured to excavate a bore and sensors coupled to the boring tool. The sensors are spaced apart from one another at multiple azimuthal locations around the steerable boring tool and the sensors are configured to detect a mineral property in the earth adjacent the steerable boring tool.

Abstract: A method of pressure testing a well tool can include applying positive or negative pressure to an internal chamber of the well tool, or determining a reference pressure, and monitoring the pressure in the internal chamber using a pressure sensor in the internal chamber. Another method can include applying pressure to an internal chamber of a well tool at a surface location, thereby creating a pressure differential in one direction across a seal, and installing the well tool in a well, thereby creating another pressure differential in a possibly opposite direction across the seal. A well system can include a well tool including an internal chamber, and a pressure sensor disposed in the chamber, whereby the pressure sensor detects pressure within the chamber.

Abstract: Just above an oil wellbore, an example circumferential displacement tool grips a threaded coupling in performing a circumferential displacement method of properly tightening the coupling to an upper sucker rod and/or to a lower one. In some examples, upper and lower joints of the coupling are tightened sequentially and independently to ensure proper circumferential displacement at each joint. In some examples, during disassembly of a string of rods being withdrawn from the wellbore, the tool can unscrew the coupling selectively from either the upper rod or the lower one. In some examples, a controller monitors the tightening or unscrewing of a joint and derives a joint signature based on a series of torque and rotation readings sampled during the make or break operations. The controller, in some examples, identifies a defective joint by comparing the joint signature to a predetermined reference.

Abstract: A sensing subassembly for use with a downhole tool comprises a housing, a cavity disposed within the housing, at least one electronic component disposed within the cavity, and at least one isolating member disposed within the cavity. The at least one isolating member is configured to attenuate at least a portion of frequency components of a mechanical wave above a threshold and transmit at least a portion of frequency components below the threshold to the at least one electronic device.

Abstract: An exercise tool assembly for operating a downhole tool auxiliary to a primary actuator system of the downhole tool includes a cylinder mandrel configured to be received in the central bore of the downhole tool. A piston mandrel is in and sealed with the cylinder mandrel. The exercise tool assembly is configured to couple to an actuator sleeve of the downhole tool and to couple to the downhole tool at a location apart from the actuator sleeve. The piston mandrel is responsive to a change in pressure in the central bore to translate relative to the cylinder mandrel and translate the coupling with the actuator sleeve relative to the coupling at the location apart from the actuator sleeve.

Abstract: A method and apparatus is provided for off-line concentration determination of components liquid hydrocarbon mixtures such as crude or heavy oil. A sampling unit continuously delivers a sample volume to a fluid flow path while a temperature control module maintains the sample at a predetermined setpoint temperature. A homogenization module helps prevent sample stratification while a flow control module maintain a constant sample flow rate. A spectrometer is communicably coupled to an optical transmission cell to transmit and receive radiation. The transmission cell includes collection optics to capture and aggregate non-collimated radiation emerging from the cell, for transmission to the spectrometer. The spectrometer measures sample spectra at a predetermined rate of flow of the sample volume through the transmission cell. A processor is configured to capture and use the spectra in combination with a model of spectra for the hydrocarbon mixture.

Abstract: A hang-off tool for supporting a tool inside a tubular member includes a logging string configured to generate logging data, a computing system coupled to the logging string and configured to communicate the logging data to another tool, and a radially expandable member having a retracted position and an expanded position. The radially expandable member is configured to engage a radially-increased profile of an inner surface of the tubular member in the expanded position to support the hang-off tool. The radially expandable member is also configured not to engage the radially-increased profile in the retracted position.

Abstract: The techniques herein relate to a pressure compensation system for a sensor in a wellbore having a wellbore fluid therein. The system includes a downhole tool (104) and at least one pressure compensator (112) positionable therein. The pressure compensator includes a first compensating fluid section having a first compensating fluid (238) therein, a first pressure compensation section having a first pressure regulation device (226) for adjusting a compensation pressure of the first compensating fluid based on a wellbore pressure of the wellbore fluid, at least one second compensating fluid section having a second compensating fluid (252) therein, and at least one second pressure compensation section having a second pressure regulation device (246) for adjusting a sensor pressure of the second compensating fluid based on the compensation pressure of the first compensating fluid.

Abstract: A method for mobilizing viscous hydrocarbons in a reservoir includes (a) injecting an aqueous solution into the reservoir with the reservoir at the reservoir ambient temperature. The aqueous solution includes water and a water-soluble chemical agent that is substantially non-decomposable and substantially non-reactive in the reservoir at the reservoir ambient temperature. In addition, the method includes (b) adding thermal energy to the reservoir at any time after (a) to increase the temperature of at least a portion of the reservoir to an elevated temperature greater than the ambient temperature of the reservoir. Further, the method includes (c) in response to the elevated temperature in (b), mobilizing at least a portion of the hydrocarbons in the reservoir by reducing the viscosity of the hydrocarbons and allowing the chemical agent to enhance mobilization of the hydrocarbons.

Abstract: The present disclosure provides a system for and method of preparing a wellbore for improved recovery from a formation and a method of producing hydrocarbons from a formation. The system includes an approximately horizontal wellbore in a formation, a liner enclosing a portion of the approximately horizontal wellbore; and a packer inside the liner that comprises a swellable elastomeric material.

Abstract: A wellbore servicing system comprising one or more wellbore tool nodes disposed within a wellbore, wherein each of the one or more wellbore tool nodes is configurable from a first configuration to a second configuration, and a controller node, wherein the controller node communicates with the wellbore tool node via a near field communication (NFC) signal.

Abstract: The present disclosure relates the methods of treating a subterranean formation. In various embodiments, an acidic treatment fluid can be injected through tubing while a non-acidic fluid is pumped through an annulus. In various embodiments, acidic treatment fluid can be pumped through coiled tubing while at least one of acidic treatment fluid and non-acidic fluid are pumped through a second tube surrounding the coiled tubing and an annulus disposed the second tube and a borehole. Various embodiments also include methods for stimulating a well and acidization of the subterranean formation.

Abstract: A method and an apparatus for managing a subterranean formation including collecting information about a flow control valve in a wellbore traversing the formation, adjusting the valve in response to the information wherein the adjusting includes a Newton method, a pattern search method, or a proxy-optimization method. In some embodiments, adjusting comprises changing the effective cross sectional area of the valve. A method and an apparatus for managing a subterranean formation including collecting information about an inflow control valve in a wellbore traversing the reservoir and controlling the valve, wherein the control includes a direct-continuous approach or a pseudo-index approach.

Abstract: This disclosure relates to systems, methods, and devices useful for monitoring and controlling water that has been used in, for example, oil and natural gas production, recovery, or hydraulic fracturing processes. An on-line unit for measuring, controlling, and optimizing the quality of produced water after being used in a hydrocarbon production or hydraulic fracturing process is also disclosed. Optimizing and controlling can include measuring one or more properties associated with the produced water to be sure that the one or more properties are within an acceptable range and, if the one or more properties are not within the acceptable range for each respective property being measured, causing a change in flow of one or more fresh water sources and/or one or more chemicals into the produced water.

Abstract: A system for and methods of producing hydrocarbons from a formation. A method may include drilling a wellbore in a formation, forming a first fracture in the formation that emanates from the wellbore, forming a second fracture in the formation that emanates from the wellbore and is approximately parallel to the first fracture, and simultaneously (a) injecting a fluid from an injection tubing string in communication with the second fracture and (b) producing hydrocarbons that travel from the first fracture into a production tubing string that is substantially parallel to the injection tubing string. The wellbore may be substantially horizontal. The fluid may increase pressure in an area of the formation adjacent to the first fracture.

Abstract: A method for recovering viscous hydrocarbons from a reservoir in a subterranean formation includes (a) injecting steam into the reservoir. In addition, the method includes (b) injecting a thermally activated chemical species into the reservoir with the steam during (a). The thermally activated chemical species decomposes at a temperature between 40° and 200° C. Further, the method includes (c) decreasing the viscosity of the hydrocarbons in the reservoir during (a) and (b). Still further, the method includes (d) mobilizing at least some of the hydrocarbons in the reservoir.

Abstract: A wellbore servicing system comprising two or more sensing, tool nodes, wherein each of the sensing, tool nodes are configured to selectively allow, disallow, or alter a route of fluid communication between an axial flowbore thereof and an exterior thereof via one or more ports, and wherein each of the sensing, tool nodes are further configured to monitor at least one parameter, and a logging controller node wherein the logging controller node communicates with the sensing, tool nodes via a near field communication (NFC) signal.

Abstract: A method for recovering viscous hydrocarbons from a reservoir in a subterranean formation includes (a) injecting steam into the reservoir. In addition, the method includes (b) injecting a surfactant into the reservoir with the steam during (a). Further, the method includes (c) decreasing the viscosity of the hydrocarbons in the reservoir with thermal energy from the steam. Still further, the method includes (d) emulsifying the hydrocarbons with the surfactant during (b) and (c). Moreover, the method includes (e) mobilizing at least some of the hydrocarbons in the reservoir.

Abstract: A well tool comprising a housing comprising ports and defining a flow passage, an actuator, a dual magnetic sensor actuation assembly (DMSAA) in signal communication with the actuator and comprising a first magnetic sensor up-hole relative to a second magnetic sensor, and an electronic circuit comprising a counter, and wherein, the DMSAA detects a magnetic signal and determines the direction of movement of the magnetic device emitting the magnetic signal, and a sleeve slidable within the housing and transitional from a first position in which the sleeve prevents fluid communication via the ports to a second position in which the sleeve allows fluid communication via the ports, wherein, the sleeve transitions from the first to the second position upon recognition of a predetermined quantity of magnetic signals traveling in a particular direction.

Abstract: There is provided a system for producing oil from a well bore extending through a fossil fuel reservoir. The system includes a plurality of perforations defined in the casing proximate the fossil fuel reservoir. A gas flow tube is in communication with the annulus volume of the casing proximate the wellhead. A gas valve is coupled to the gas flow tube, with the gas valve configured to selectively open and close the gas flow tube. A controller, is coupled to the gas valve, with the controller configured to control the opening and closing of the gas valve. The opening and closing of the gas valve maximizes the volumetric rate of oil flow into the annulus volume through the perforations from the reservoir by displacing liquid in the annulus volume with a gas volume between the gas valve and the perforations.

Abstract: A completion apparatus (4) for completing a wellbore comprises a) a tool to alternatively open and close a throughbore (15) of the completion; b) a tool (13) to alternatively open and close an annulus defined between the outer surface of the completion and the inner surface of the wellbore; c) a tool to alternatively provide and prevent a fluid circulation route from the throughbore of the completion to the said annulus (11); and d) at least one signal receiver and processing tool (9) capable of decoding signals received relating to the operation of tools a) to c).

Abstract: A technique for determining conditions downhole in a well, particularly load conditions acting on a well tool, e.g. a bottom hole assembly. The loads acting on a bottom hole assembly or other well tool during a well related operation are measured. Load data is collected and may be transmitted uphole in real time for evaluation at a surface control unit. Based on the load data and other possible data related to the downhole operation, corrective actions can be taken to improve the operation.

Abstract: In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

Abstract: A method of evaluating a stimulation operation includes: receiving parameter information for the stimulation operation, the stimulation operation including injecting an acid stimulation fluid into an earth formation along a selected length of a borehole from a tubular disposed in the borehole; and generating, by a processor, a thermal model based on one or more energy balance equations that account for at least a first heat source and a second heat source, the first heat source expected to produce heat during the stimulation by a chemical reaction between an acid in the stimulation fluid and the formation, and the second heat source including expected geothermal heat from the formation.

Abstract: Embodiments of this invention relate to compositions and methods of processing a subterranean formation including collecting microseismic data from one wellbore, collecting amplitude ratio information for the microseismic data, comparing the amplitude ratio to an expected ratio, generating a representation of a formation based on the microseismic data and the comparison of the amplitude ratio and expected ratio, and performing an oil field services activity based on the representation.

Abstract: A method for detecting the geometry of underground fractures comprising: introducing a filling material (14) into an underground fracture (11) to form a pack of filling material (14); transmitting an electromagnetic field into the fracture (11); detecting at least one reflected signal of the electromagnetic field transmitted; and processing the at least one detected signal to reconstruct the geometric and dimensional characteristics of the pack of filling material (14); wherein the electromagnetic field transmitted into the fracture (11) has a frequency comprised in the range of between 30 megahertz and 250 megahertz and in that said filling material is not added with any additives; and a system for implementing the aforementioned method.

Abstract: A fracturing system including a ring gasket disposed between a fracturing tree and a wellhead component is provided. In one embodiment, the ring gasket includes multiple sealing stages that seal against grooves in the fracturing tree and the wellhead component. The ring gasket may also include one or more recesses between the sealing stages. In some embodiments, the ring gasket has a configuration that reduces gasket setting load and increases flange separation load compared to other gaskets used in fracturing operations. And in some embodiments, the system enables monitoring of gasket sealing integrity, even during fracturing operations. Additional systems, devices, and methods are also disclosed.

Abstract: A thermal recovery method employing an electrical pre-heating method to condition the hydrocarbon-bearing formation as a means of improving recovery when steam injection is later applied. In addition, a method of comparing the applied electrical flux and resulting temperature profile to determine the heat transfer properties of each of a plurality of reservoir regions along the length of a horizontal well is disclosed. Advantageously, the heat flux supplied to each of the regions may be varied relative to each other region to compensate for different thermal transfer properties which may exist in the formation within each of the regions. Such controlled variation in thermal energy transfer, compensating for variances in fluid mobility and thermal properties in the reservoir allows for a more even steam chamber development and therefore optimized oil recovery.

Abstract: A well watchman pumping and control system that is capable of operating in a wide range of ambient conditions. The system automatically maintains water level in a water storage vessel, while protecting the pump and generator from operating in conditions outside preset operating parameters to prevent premature failure and reduce repair. By operating to pump water only when preset operating conditions exist, e.g. low water level, ambient temperature, etc., the system reduces labor, fuel, and maintenance operating costs to the owner, improves well pumping reliability and production, reduces generator fuel consumption, reduces emissions, and conserves ground water.

Abstract: Generally, the present disclosure is directed to noise isolation tools that may be used to minimize or even eliminate the detrimental effects that rogue noise events may have on the noise data acquired by a noise logging tool during a noise logging operation. In one illustrative embodiment, a noise isolation tool that is adapted to be used in a noise logging operation is disclosed, the noise isolation tool including, among other things, a body and at least one noise suppression element mounted on the body, the at least one noise suppression element having a substantially circular disc shaped configuration that is adapted to extend radially across at least a portion of a width of an annular space between the body and an inside surface of a wellbore casing during the noise logging operation.

Abstract: A wellbore servicing tool comprising a housing comprising one or more ports and generally defining a flow passage, an actuator disposed within the housing, a magnetic signature system (MSS) comprising a magnetic sensor in signal communication with an electronic circuit disposed within the housing and coupled to the actuator, and a sleeve slidably positioned within the housing and transitional from a first position to a second position, wherein, the sleeve is allowed to transition from the first position to the second position upon actuation of the actuator, and wherein the actuator is actuated upon recognition of a predetermined quantity of predetermined magnetic pulse signatures via the MSS.

Abstract: An apparatus for determining a closure pressure of a fractured formation surrounding a wellbore is disclosed. The apparatus, in one embodiment, includes an isolation device for isolating a section of the wellbore, a fluid supply unit for supplying a fluid from the wellbore under pressure into the isolated section of the wellbore to cause a fracture in the formation proximate the isolated section, a receiving unit for receiving fluid from the isolated section at a constant or substantially constant rate due to pressure difference between the formation and the receiving unit, and a sensor for determining pressure of the formation during receiving of the fluid into the receiving unit. The apparatus further includes a controller for determining the closure pressure from the determined pressure.