The New STANDARD in Well Logging. Specialty Cased Hole Logging Technical Catalogue. Technical and Training

Transcription

1 The New STANDARD in Well Logging Specialty Cased Hole Logging Technical Catalogue 2012 April 2012 Technical and Training

2 Specialty Cased Hole Technical Catalogue 2012 Prior to the completion of any well, it is a requirement to obtain reliable and detailed information necessary to determine not only the possibility of the presence of hydrocarbons, but also for the definitive and quantitative evaluation of formations and lithologies, cementing, hydraulic isolation and casing integrity in order to expand database information on fields and regions. Once the well is producing/on production, additional tools can be employed to evaluate completions effectiveness, quantify production rates, identify possible well problems or diagnostics, identify fluid sources, perform casing inspection and evaluate fracturing effectiveness. Secondary depth control correlation Cement evaluation Cement compressive strength Formation porosity Bulk Density Delineate gas zones from annular excavations & fresh wet sands Identify water source(s) Frac program evaluation Shale volume Formation evaluation Casing inspection Hydrocarbon indication Monitor steam flood & acid treatments Monitor gas cap movement Flowing profile/regime charecteristics evaluate cement effectiveness incl. zone hydraulic isolation for completions Multi-well integration Identify coal seams Identify by-passed pay intervals Well diagnostic By combining the specific information of Specialty Cased Hole Logs with other petrophysical information and combining geophysical, regional and adjacent well data, definition of reservoir and regional parameters can be established. This can then result in more efficient completion and/or remediation programs being compiled and executed. BENEFITS TO YOU Our dedication to quality, consistency and competence, along with the long established commitment to research and development of new and innovative technology to enhance data acquisition capabilities will ensure that your company can make the necessary decisions based on precise and accurate data. These services are provided to your company at the highest standards the industry has to offer. SERVICES Depth capacities to 20,000 ft / 6,000m Temperature capabilities up to 350 F / 176 C (for 1 hour exposure) Pressure capabilities up to 12,000 psi (82.7 MPa) Tool OD: 1 3/8 (35 mm) and 1 11/16 (43 mm) allow logging in a variety of tubing and pipe sizes Hostile environment (eg. H 2 S, CO 2, etc) available on request Deviated hole logging up to 69 (on gravity descent), 90 Horizontal with Coil Tubing, e-coil or Well Tractor Deployment in Extended Reach or Horizontal well applications Memory Mode Capable for Slickline, Coil Tubing and Well Tractor Deployment Tool String can be stacked in various configurations 2

3 Specialty Cased Hole Technical Catalogue 2012 DOWNHOLE SERVICES AVAILABLE STANDARD PRODUCTION LOG PLATFORM Deployment Digital Telemetry (XTU) Memory Mode Capable (UMT) Correlation: Gamma Ray (PGR / GR) Casing Collar Locator (CCL) Fluid Identification: Capacitance (CWH) Fluid Density Tool (FDR) Environmental Temperature (TEMP) Quartz Pressure Gauge (QPG) Production Flow Rate Production Flowmeter (FLOW) Continuous Full Bore Flowmeter (CBF) In-line Flowmeter (ILF) HIGH DEFINITION PRODUCTION LOG PLATFORM Deployment Digital Telemetry (XTU) Memory Mode Capable (UMT) Correlation: Gamma Ray (PGR / GR) Casing Collar Locator (CCL) Fluid Identification: Capacitance (CWH) Fluid Density Tool (FDR) Gas Holdup Tool (GHT) Environmental Temperature (TEMP) Quartz Pressure Gauge (QPG) Production Flow Rate Production Flowmeter (FLOW) Continuous Full Bore Flowmeter (CBF) In-line Flowmeter (ILF) HORIZONTAL PRODUCTION LOG ACESSORIES Fluid Identification: Resistivity Array Tool (RAT) Capactiance Array Tool (CAT) Production Flow Rate Spinner Array Tool (SAT) MECHANICAL SERVICES TOOLS Cement Evaluation: Cement Bond Tool (CBL) Radial Bond Tool (RBT) Casing Inspection Multi Finger Imaging Tool (MIT) THROUGH CASING FORMATION EVALUATION TOOLS Porosity: Compensated Dual Spaced Density (DSD) Compensated Neutron (Thermal) (DSN) 3

4 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 Production Gamma Ray (PGR) Gamma rays are detected by a high temperature sodium iodide crystal and amplified using a 10 stage photo-multiplier to a measurable level. The detector is temperature compensated to minimize photo-multplier drift. Calibration is maintained by a wrap-around calibrator with a distributed thorium source of very low radioactive content. The difference between background and calibrated levels provides a ratio between tool count rate and API units. Lithology identification Depth correlation Derive a GR Index to perform Vsh corrections Identification of radioactive scale Frac Tracer monitoring Gravel Pack monitoring (with addition of a gamma source) The PGR gamma tool measures natural gamma radiation (KUT) from the formation surrounding the wellbore or for other specialty applications, such as radioactive tracing. The detector is comprised of a 4 Nal scintillation crystal, photomultiplier and 1.6kV high voltage power supply. All models are compact and rugged. They also combine excellent sensitivity with high resolution for cased hole production logging applications. Tools can be combined for tracer work and with the addition of a gamma source can be used for gravel pack investigations. 1 3/8 (35 mm) 19.7 (500 mm) 5.1 lbs (2.3 kg) 350 F (177 C) 15,000 psi (103 MPa) Threshold 20 kev Sensitivity 1 count per API Deadtime Negligible Accuracy <10% Measure Point 4.6 (117 mm) 4

5 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 Fluid Density (FDR) Gamma rays are emitted by the Am 241 source at one end of a 101.6mm measuring cell through which the well fluid passes, and are detected at the opposite end by a Nal scintillation detector and photomultiplier. The count rate is a logarithmic function of the fluid density. For greater accuracy and resolution the detector is temperature stabilized and matched to the gamma ray energy of the source. The tool is calibrated in multiple medias to derive calibration values encompassing the range from gas to high-salinity waters. Multi-phase production profiling Fluid identification Horizontal / highly deviated wells High fluid flow rates The FDR provides a reliable, durable and safe means of measuring fluid density and flow rates. The tool uses a low energy Americium-241 gamma ray source with radiation levels approaching background at a distance of only one metre from the tool. This shielded tool has been designed to be immune to the effects of radioactive scale and very high count rates. The shield can be locked on the tool so that the source can be left in place between jobs. Range Resolution Accuracy Source Measure Point 1 3/8 (35 mm) 22.9 (581 mm) 6 lbs (2.7kg) 350 F (177 C) 15,000 psi (103 MPa) 0 to 1.25g/cc 0.01 g/cc 0.03 g/cc Am 241, 5.5GBq (150mCi) 4.3 (110 mm) 5

6 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 Quartz Pressure / Casing Collar Locator (QPC/CCL) The resonant frequency of a shaped quartz crystal varies with the applied pressure. This variation has to be compensated for changes of crystal temperature, hence both pressure & temperature outputs are available from the gauge. Using this data and a calibration supplied with the gauge, an accurate and high resolution pressure reading is available over wide measurement ranges. An available pseudo-density may be derived from the pressure response data. Changes in the amount of magnetic material around the tool causes variations in the magnetic field that is produced by two strong magnets mounted either side of a coil. These variations induce an electromagnetic field (EMF) within the coil which is processed to produced the collar log. Depth control in casing and tubing Location of severe casing or tubing damage Confirmation of perforation depths/intervals Data for Productivity Index (PI) and Nodal analysis Draw-down and build-up pressure transient analysis (PTA) Down-Hole pressure gradient measurement The combined quartz pressure & CCL tool is designed to minimize tool length. It uses a Quartzdyne gauge fitted with a bellows to provide isolation from wellfluids. Pressure access is via a single filtered port available for use during maintenance. The co-axial CCL uses a pair of rare earth magnets & a single coil to detect casing collars & other variations of magnetic material surrounding the tool. 1 3/8 (35 mm) (304.3 mm) 3.7 lbs (1.7 kg) 177 C (350 F) 15,000 psi (103 MPa) Resolution <0.008 psi & <0.005 C Pressure Accuracy Max. total/ combined error 0.02% FS Temperature Accuracy +/- 0.1 C Pressure Respons <1 second for 99.5% Pressure Aging <3 psi/ year Depth Offset 0.6 Pressure; 8 CCL 6

7 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 Capacitance / Temperature / Flowmeter (CTF) Capacitance Water Hold-Up (CWH): Hydrocarbons and water have different dielectric constants. The output frequency of the probe is in response to the average dielectric constant of the fluids between the cage of the tool and the inner probe. From this the down hole water to hydrocarbon ratio can be derived. Temperature: The sensor uses a platinum resistance probe, which changes resistance with temperature. The output signal is multiplied within the electronics to convert to extremely high resolution. The probe tip is very small resulting in a very rapid (0.5 sec) response time. Flowmeter Electronics: Dual magnets are fitted to the flowmeter main shaft which close Hall effect sensors/switches as the shaft rotates. 5 pickups give a directional output of 10 pulses per revolution. Fluid compositon from average dielectric constant Fluid ID from temperature response Location of leaks and crossflow by temperature response Quantitative measurement of flowrate in casing and tubing As a part of the short combination tool string (SCT) the CTF sensors, together with their electronics section, provide these basic PL measurements within a short tool length. The flowmeter mechanical section is interchangeable with others to provide a wide range of flowmeter options including ultralow flow rates, such as those encountered in CBM and other unconventional resources. The short distance between these three basic sensors means that the fluid measurement are essentially taken from the same sample, offering a six-fold increase in resolution. In the case of standard PL tools, the equivalent three (3) sensors will be at least six (6) times further apart and, in a heterogeneous flow, are less likely to be providing measurements within the same fluid sample simultaneously. Continuous and Fullbore Spinner Mechanical Sections 7

8 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 CAPACITANCE WATER HOLD-UP / TEMPERATURE 1 3/8 (35 mm) (0.47 m) 4.0 lbs (1.81 kg) 350 F (177 C) 15,000 psi (103 MPa) Temp Measure point 8.72 (0.22 m) CWH Measure point 5.34 (0.13 m) Power Supply ma CWH Resolution 1% CWH Range 0-45% Water Hold-up Temp. Resolution F Temp. Accuracy +/- 1 F Temp. Response <0.5 seconds Flowmeter Output 10 pulses/revolution Material FLOWMETER 1 3/8 (35 mm) and 1 11/16 (43 mm) 2.91 ft (890 mm) * 10 lbs (4.5 kg)* 350 F (177 C) 15,000 psi (103.4 MPa) Sensor Measure Point 13.5 (349 mm) Output 10 pulses/rev (directional) Sensor Threshold * ~ 1.7 ft/min (0.01 m/s), 100 bpd in 7 CSG Max Fluid Velocity 500 ft/min (2.54 m/s), 2,850 bpd in 7 CSG Casing Range 2 3/8 to 9 5/8 * Dependant on spinner & cage sizes 8

9 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 High Definition Holdup (GHT) Low energy Gamma rays are emitted by a small 3mCi Co source passing through a sleek Titanium pressure housing and undergoes a combination of Compton Scattering and Photoelectric Absorption by the fluids in the well. The short detector-source spacing results in the dominate signal reading being from gamma rays that have been back-scattered directly from the fluids into the tool s scintillation detector. Increased salinity or density naturally tends to increase count rates due to Compton Scattering, but a unique combination of geometry and gamma ray energies ensure that this effect is counteracted by increased Photoelectric Absorption. The signal is impervious to fluids outside the casing as gamma rays are largely attenuated by the steel wall on the combined outgoing and return journey. The tool is calibrated before the job using a 4.67 calibration fixture and may be checked immediately before running in hole (RIH) using a portable tool verifier. The tool is housed within a sheilded carrying case that alleviates the need for source insertion/removal. Multi-phase production profiling Fluid identification Bubble Point determination Gas entry detection The High Definition Holdup Tool was originally developed to provide a reliable means of measuring cross-sectional well bore gas volume fraction in any flow regime and well bore deviation. The tool response is representative of the entire cross-section of the well bore within the casing and is almost completely independent of salinity, water cut and oil/water densities. 1 11/16 (43 mm) 27 (686 mm) 10 lbs (4.5kg) 350 F (177 C) 15,000 psi (103 MPa) Range 0-100% gas Holdup within pipe Accuracy ± 3% Resolution 1% Vertical Resolution 2.5 (64 mm) approx. Source Cobalt 57 3mCi, Cobalt MBq 9

10 Specialty Cased Hole Technical Catalogue: Production Logging Platform 2012 DEPLOYMENT TOOLS Digital Telemetry RECONs High Definition Specialty Cased Hole Logging Digital Telemetry is a sophisticated system that enables industry s highest standard data acquisition, protection, durabilty and versatility. The Telemetry allows Specialty Cased Hole tools to be a Memory Mode Capable system controlled by a surface laptop and battery powered. Programming is written into the Telemetry tool before the commencement of a job with the commands to collect data over pre-programmed intervals and operate any motorized tools in the string. Data is downloaded after the completion of the job and confirmed for data quality control. The data is then merged with a depth file to complete the data set. 1 11/16 (43 mm) 1 3/8 (35 mm) (652 mm) 25.0 (635 mm) 10.6 lbs (4.8 kg) 9.5 lbs (4.32 kg) 350 F (177 C) 350 F (177 C) 15,000 psi (103 MPa) 15,000 psi (103 MPa) Voltage and Current Memory Sample Rates to +20 VDC / 25 ma (5 ma on Stand-By) 128 MB, 4 MB/min, typical download (computer dependent) 20 ms minimum up to several days (in 20 ms increments) Depth Time Recorder (DTR) Depth information is recorded on surface versus time. All logging data recorded versus time from the tools is then merged to create an API standard log output post-job. 10

11 Specialty Cased Hole Technical Catalogue: Horizontal Production Logging 2012 Spinner Array Tool (SAT) Discreet local fluid velocities are obtained through a series of six (6) miniature flowmeters / spinners deployed on bowspring arms at 60 intervals ensuring 360 wellbore coverage. Traditional correlations have used the total fluid velocity and then estimated the individual phase velocities; lighter phases migrate to the high side of the well, the heavier phases to the low side. The SAT allows direct measurment of the individual fluid phase flow at their own unique velocities and directions incorporated with a relative bearing measurement to indicate high side of the well. Phase velocity segregation in deviated, highly deviated & horizontal wells Direct measurement of individual phase velocities present Plotting of phase velocities across the wellbore Identification of water entry/production loss areas Changes in wellbore fluids with time/different production rates The Spinner Array Tool is designed to accurately measure individual fluid phase velocities in deviated, highly deviated or horizontal wells. Run centralized within the wellbore, it is ideally combined with an Inclinometer tool to aid interpretation. The array of 6 highly sensitive flowmeters mounted on bowsprings enables a full wellbore profile whether running in or out of the well, minimizes power requirements and provides greater tolerance to well debris. Each sensor of the array measures the velocity of the surronding fluid close to the well casing, all 6 values are simultaneously transmitted to the surface or into a memory section. Due to the measurement points being situated in a single plane across the diameter of the wellbore, rather than spaced along it, an accurate cross-sectional plot can be generated of fluid velocity. Combined with Production Inclination Accelerometer (PIA) to give well inclination 1 11/16 (43 mm) 45.5 (1,156 mm) 17.2 lbs (7.8 kg) 350 F (177 C) 15,000 psi (103 MPa) Number of Fluid Sensors 6 Flowmeter 0.4 (10 mm) Sensor Measure Point 16.5 (419 mm) PIA Orientation Sensor Indicates which sensor is up Maximum Pipe Size 7 casing. *Tool available upon request with sufficient lead time. 11

12 Specialty Cased Hole Technical Catalogue: Horizontal Production Logging 2012 Resistivity Array Tool (RAT) The cross-sectional water holdup profile is determined through a series of 12 micro resistance sensors mounted on bowsprings at 30 intervals, ensuring 360 borehole coverage. Oil, gas and water have different conductivities; water (brine) is conductive, while oil and gas are non-conductive. The RAT incorporates a relative bearing measurement to indicate the high side of the well. Water Holdup in vertical, deviated, highly deviated & horizontal wells Cross-sectional water holdup profiling Phase segregation mapping along the wellbore Identification of water entry/production loss areas Changes in wellbore fluids with time/different production rates The Resistance Array Tool differentiates between conductive water and non-conductive hydrocarbons and will detect very small, fast moving bubbles. The RAT provides the cross-sectional water holdup profile in vertical, deviated, highly deviated or horizontal wells. Run centralized within the wellbore, it is ideally combined with an Inclinometer tool to aid interpretation. The array of 12 specially developed miniature resistance sensors mounted on the inside of a set of bow-springs enables a full wellbore profile. Each sensor of the array measures the resistance of the surrounding fluid close to the well casing, all 12 values are simultaneously transmitted to the surface or into a memory section. Due to the measurement points being situated in a single plane across the diameter of the wellbore, rather than spaced along it, an accurate cross-sectional plot can be generated of water holdup. The use of bow-springs allows the tool to be used running in or out of the well to minimizes power requirements, particularly when deployed using memory mode. Combined with Production Inclination Accelerometer (PIA) to give well inclination 1 11/16 (43 mm) 51.4 (1,306 mm) 18.0 lbs (8.2 kg) 350 F (177 C) 15,000 psi (103 MPa) Number of Fluid Sensors 12 Sensor Measure Point 15.7 (399 mm) PIA Orientation Sensor Indicates which sensor is up Maximum Pipe Size 7 casing. *Tool available upon request with sufficient lead time. 12

13 Specialty Cased Hole Technical Catalogue: Horizontal Production Logging 2012 Capacitance Array Tool (CAT) The output frequency of a sensor changes with the dielectric constant of the fluid surrounding it. Oil, gas and water have different dielectric constants. By making a simple calibration of the sensors this enables for the identification of the fluid distribution surrounding each sensor. This allows for the identification of multiple phases within the wellbore. Phase identification in horizontal & highly deviated wells Calculation of phase percentage present Plotting of phase composition along the wellbore Identification of water entry/production loss areas Changes in wellbore fluids with time/different production rates The Capacitance Array Tool is designed to solve for accurate fluid phase identification in horizontal or highly deviated wells. Run centralized within the wellbore it is ideally combined with an Inclinometer tool to aid interpretation. The array of 12 radial capacitance sensors mounted on bow-springs enables a full wellbore profile. Each sensor of the array measures the capacitance of the surrounding fluid close to the well casing, all 12 values are simultaneously transmitted to the surface or into a memory section. Due to the measurement points being situated in a single plane across the diameter of the wellbore, rather than spaced along it, an accurate cross-sectional plot can be generated of fluid distribution. CAT View software can be used to provide a 3D image of the phases along the well. The use of bow-springs allows the tool to be used running in or out of the well to minimizes power requirements, particularly when deployed using memory mode. Combined with Production Inclination Accelerometer (PIA) to give well inclination 1 11/16 (43 mm) (1,306 mm) 17.3 lbs (8.1 kg) 350 F (177 C) 15,000 psi (103 MPa) Number of Fluid Sensors 12 Sensor Measure Point 18.2 (462 mm) PIA Orientation Sensor Indicates which sensor is up Maximum Pipe Size 7 casing. *Tool available upon request with sufficient lead time. 13

14 Specialty Cased Hole Technical Catalogue: Mechanical Integrity 2012 Multi Finger Imaging Tool (MIT 24 Finger) The 24 finger Multi Finger Imaging Toll (MIT) is used to detect very small changes to the internal surface condition of tubing or casing with a high degree of accuracy. The MIT can be run through tubing to log casing deeper within a well. Casing inspection Quantification of scale build-up and corrosion Accurate location of anomalies Identification of items within tubing, buckling and damage Suitable for all well deviations including horizontal 3D visualization capabilities The MIT uses a 24 finger caliper arrangement to maintain maximum internal surface coverage within the tubing/casing Internal (ID). The fingers are closed when running in hole to prevent damage; once at logging depth, the fingers are opened and a continuous measurement of the pipe s internal surface condition is made as the tool is logged up. An inclinometer in the tool indicates finger position relative to the high side of the pipe so that features can be orientated during processing. Extended length fingers available 1 11/16 (43 mm) 64.6 (1,640 mm) 20.7 lbs (9.38 kg) 350 F (177 C) 15,000psi (103MPa) STANDARD EXTENDED Measurement Range ( mm) ( mm) Radial Resolution (0.051 mm) (0.076 mm) Radial Accuracy ± 0.02 (0.508 mm) ± 0.02 (0.508 mm) Finger Tip Width (1.60 mm) (1.60 mm) Finger Contact Force lbf ( N) lbf ( N) Vertical Resolution (1.27 ~ 30 f/min (10 m/min) 14

15 Specialty Cased Hole Technical Catalogue: Mechanical Integrity 2012 Radial Bond Tool (RBT) Cement Bond Log (CBL) The RBT measurment is based upon the prinicples of Sonic Attenuation. A traditional Cement Bond Log (CBL) measures the amplitude of a sonic signal passing along the casing; the signal is reduced where the casing is bonded to the cement. While cement bonds that are either complete, or totally absent, can be clearly identified, signals showing partial bonds provide insufficent data to determine hydraulic isolation. The RBT overcomes this problem by using six (6) receivers positioned circumferentially around the tool. Each receiver provides bond data covering a 1/6 th sector of the casing, generating a six segmented map of the cement in additon to the conventional CBL and VDL (Variable Density Log). Cement bond evaluation Cement channel identification Bond index calculation (hydraulic isolation effectiveness) Bond attenuation measurement Cement compressive strength Simultaneous cement bond and casing inspection Compressional delta T (computed product), DT The RBT evaluates cement bond integrity using a unique slotted sleeve technology that provides superior isolation, rigidity and tool strength. Six segmented piezoelectric crystal sensors cover a full circumferential sweep and are able to detect minute channels in the cement and display it as a radial cement map. Compressional Delta T (DT) can be derived via post processing if adequate bond conditions exist. Receivers Measurement Borehole Fluids 1 11/16 (43 mm) (3,320 mm) 40 lbs (18.1 kg) 350 F (177 C) 20,000 psi (138 MPa) Piezoelectric Crystal (2 ft spacing) 6-Channel Radial, 3 and 5 Acoustic Oil, Fresh Water, Brine 15

16 Specialty Cased Hole Technical Catalogue: Through Casing Formation Evaluation 2012 Gravel Pack Density (GPD) The Gravel Pack Density consists of a scintillation Gamma section with a source/feedthrough sub attached to the bottom. The source sub accomodates a gamma source of up to 150mCi (5.5GBq) of 137 Cesium. The GPD can be used at the bottom of a toolstring or stacked with additional tools below. In either case the tool functions best when run centralized. When in use the tool is essentially considered an omni-directional density tool. Gamma rays from the source are detected at a rate dependent upon the variation of the total density of a volume of material, with a roughly spherical volume, centered on the tool measuring point. When examining the condition of a gravel pack the variation is normally due to changes in the packing order of porosity. Detection of voids in the gravel pack Monitoring of changes in porosity with time Cavern interface logging Locating voids behind casing Gravel packs are used to prevent sand from flowing into the well while still allowing continuous rapid production. The construction consists of a slotted or perforated liner placed in the well and surrounded by small-sized gravel. The well is enlarged by underreaming at the point where the gravel is packed. During placement or throughout the life of the well, voids can occur whereby sand has an easy ingress route; this does not normally happen where resin bonded packs are used. Additionally, sand filling the interstitial spaces between the gravel pack can be identified with a log to provide an analysis of the areas in the pack that need to be replaced before the well is placed either on production or as a remediation solution for wells on production. Sand blocking of the pack that can be identified, which can potentially reduce production, provides information that there is a well construction issue rather than a reservoir problem that is reducing yield. 1 11/16 (43 mm) (1,028 mm) 13.3 lbs (6 kg) 350 F (177 C) 15,000 psi (103 MPa) Detector Scintillation Gamma Section 26.6 (676 mm) Source Sub (352 mm) Measure Point 8.88 (226 mm) Source/Detector spacing (451 mm) Gamma Source 5.5G Bq (150 mci) Cesium

17 Specialty Cased Hole Technical Catalogue: Through Casing Formation Evaluation 2012 Compensated Dual-Spaced Neutron (DSN/CNL) The Compensated Neutron tool, DSN (also known as CNL Compensated Neutron Log), consists of 2 He 3 thermal neutron detectors which provide compensation for borehole, casing and cement effects. Neutron particles are emitted from an isotopic source with an average energy of 4-6 MeV. These fast neutrons collide with atomic nuclei and are slowed down until they reach a thermal energy level and are captured by a hydrogen nucleus. In situations where an abundance of hydrogen is present, such as high porosity water/oil-filled formations, the neutrons are thermalized quickly near the source. If a small amount of hydrogen is present, such as in low porosity water/oil-filled reservoirs, the neutrons must travel further before being thermalized and captured. The counts of thermal neutrons captured between the two He 3 detectors are inversely proportional to the equivalent water-filled porosity of the reservoir. Porosity measurments are calibrated for the specific matrix being logged. Determine porosity through casing (NPHI) Shale indicator Hydrocarbon indicator Monitor reservoir and fluid contacts Gas/Water contact Oil/Water contact Light and heavy hydrocarbon contact indicator Qualitative acid-stimulation treatment and steam flood effectiveness Identify up-hole hydrocarbon potential and by-passed pay The DSN is a dual-detector thermal neutron logging system designed to compensate for borehole rugosity effects and derive a porosity measurment from the ratio of the long-space and short-space count-rates. Detector Neutron Source Type Borehole Fluids Tool Positioning Far Detector (LS) Near Detector (SS) 1 11/16 (43 mm) (2,000 mm) 30.0 lbs (13.61 kg) 350 F (177 C) 18,000 psi (126 MPa) 2 He 3 type (SS & LS) GBq (18 20 Ci, Am 247 Be) Water / Oil Decentralized (796.3 mm) above the bottom of the tool (538.5 mm) above the bottom of the tool 17

18 Specialty Cased Hole Technical Catalogue: Through Casing Formation Evaluation 2012 Compensated Dual-Spaced Density (DSD) The Compensated Dual Spaced Density (DSD) uses a 150mCi (5.5GBq) Cs-137 gamma source, housed within an attached sub at the tool base. The DSD performs best when run centralized and requires adequate centralization in deviated and horiozontal applications, although in vertical wells it can be run eccentralized. Deployment is available through multiple options such as slickline, coil tubing and tractor. The DSD is ideally placed at the base of the tool string to avoid formation heating from additional sources in stack (DSN/CNL), however it is capable of being stacked at any point to accommodate multiple tool configurations. Qualitative indicator of formation Bulk Density (RHOB) through casing Collaborative indicator of gas effect in combination with DSN/CNL Lithology indicator when combined with GR, DSN/CNL, DT (From RBL/CBL) Qualitative coal quaility indicator and CBM Proximate Analysis calculations Pseudo-stress analysis (Brittle vs. Ductile) when run in combination with GR, DSN/CNL, RBT The DSD tool allows for further interpretation of rock properties and lithology otherwise not available through conventional through-casing logging tools. Gamma rays from the source are captured via scintillation detectors that are centered on the tool measuring point, at a rate dependent upon the variation in the electron density of a volume of material; which can be considered roughly spherical. Variations are due to changes in the electron density of the rock as seen through casing. The resulting data set is then post-processed and correlated to offset/adjacent open hole well data to yield a qualitative bulk density. Detector Type Measure Point Source/Detector spacing Source Sub Gamma Section Gamma Source 1 11/16 (43 mm) 40.5 (1,028 mm) 13.3 lbs (6 kg) 350 F (177 C) 15,000 psi (103 MPa) Scintillation 8.9 (226 mm) 17.8 (451 mm) 13.9 (352 mm) 26.6 (676 mm) 5.5 GBq Cs 137 (150 mci) 18