geoVISIONResistivity imaging for productive drilling

Real-time resistivity measurements from the geoVISION* imaging-while-drilling service make

drilling more productive by savingrig time and reducing costs. The high resolution of geoVISIONimages reveals formation structure and geological features,allowing wells to be steered to the best place in the reservoir to enhance production and ROI.

Multiple depths of investigationpermit detailed geological analysis to pinpoint reserves and optimize completion designs and stimulation strategies.Welcome to productive drilling*.

FLEXIBLE BHA CONFIGURATIONS

Resistivity measurements from thegeoVISION imaging-while-drillingservice can detect and image thin-bed resistivities in conductive

Resistivity imaging while drilling helps position wells in the best place in the reservoir in less time.

BENEFITS

� Cuts costs by providing key inputs for optimizing completion design and stimulation strategy

� Identifies thin bed pay zones in conductive mud environments

� Facilitates putting horizontalwells in the best place within a reservoir by showing wellborelocation relative to structure

� Saves rig time by acquiring data while drilling

� Provides accurate resistivity measurements in high-resistivity formations

geoVISION

mud environments. This informationprovides the detailed geologicalanalysis required for geosteeringprecision in wellbores as small as 81⁄2 in.

The geoVISION downhole tool canbe configured to make up to fiveresistivity measurements. Threeazimuthally focused 1-in buttonelectrodes, spaced longitudinallyalong the axis of the tool, providemultiple depths of investigation thatpermit quantification of invasionprofiles. An integral, cylindricalelectrode delivers a high-resolution,

lateral resistivity referred to as ring resistivity. A bit resistivitymeasurement allows real-time coring and casing point selection in both conductive and resistivemud environments.

Placement of the geoVISION tool in a BHA can be directly above the bit, near the bit, or above other components—allowing broad flexibility in BHA configuration. In addition to five resistivity measurements, the geoVISION tool acquiresazimuthal gamma ray data,

torsional and lateral shock records,and temperature measurements.

REAL-TIME IMAGING AND DIP CALCULATION FOR ENHANCEDWELL PLACEMENT

The azimuthally acquired electrodemeasurements are displayed as fullbore images in real time to graphically describe formation resistivity. Advanced built-in processing allows structural dip to be calculated downhole andtransmitted to the surface in realtime. This provides informationabout formation structure and

other geological features, whichaids precise placement of a wellbore within a reservoir.

All data acquired are stored inmemory and can be sent to the surface in real time or downloadedwhen the tool is returned to the surface. Advanced processing and interpretation can be done at the computing center by thesame analyst who interprets FMI* Fullbore FormationMicroImager images.

0 150(gAPI)Gamma Ray

75 25ROP

(ft/h)

MD1 : 20

Orientation Top of Hole0 360240120Resistive Conductive

Orientation Top of Hole0 360240120Resistive Conductive

-5 95(º)

Events

Concretions

Partially healed fracture

Resistive fractures

Static geoVISION Image Dynamic geoVISION Image Dynamic FMI Image

0 150(gAPI)Gamma Ray

75 25ROP

(ft/h)

MD1 : 60

Orientation Top of Hole0 360240120Resistive Conductive

Orientation Top of Hole0 360240120Resistive Conductive

-5 95(º)

Events

Static geoVISION Image

Concretion

Bed boundary

Conductive fracture (natural)

Resistive fracture (healed)

Concretion

Longitudinal induced conductive fracture

Dynamic geoVISION Image Dynamic FMI Image

The consistency of these geoVISION and FMI images, acquired over the same intervals in Barnett shale, demonstrates the abilityof geoVISION imaging while drilling to provide the resistivity measurements required for detailed geological analysis.

Put wells in the best place with high-resolution multidepth geoVISION resistivity measurements.

ACQUISITION OF HIGH-RESOLUTIONBOREHOLE IMAGES WHILEDRILLING SAVES RIG TIME AND REDUCES COSTS

The high-resolution boreholeimages provided by the geoVISIONservice facilitate detailed geologicaland geomechanical analyses inconductive mud environments. By providing the measurementsrequired to identify natural fracturescontributing to well productivity—and both the natural and inducedfractures necessary to understandthe orientation of formation stressesaround the borehole—geoVISION

imaging delivers key information for devising successful completionstrategies. Because geoVISIONresistivity imaging can be combinedwith other services, the need for an additional logging run can be eliminated, resulting in rig time savings and reduced drilling costs.

RESISTIVITY IMAGING-WHILE-DRILLING IDENTIFIES FRACTURESIN BARNETT SHALE

In an 81⁄2-in well drilled in the TexasBarnett shale, geoVISION boreholeimages were used to successfullyidentify faults, open and healed

fractures, structural and stratigraphic dip magnitudes and directions, and minimum and maximum stress orientations. A drillpipe-conveyed FMI imagerwas also run in the horizontal section of this well for comparison.The consistency in interpretation of the FMI and geoVISION images provided the validation and confidence necessary to rungeoVISION services in futureBarnett shale wells.

Reach TD in less time with productive drilling

Antrim

Devonian/Ohio

Floyd andConasauga

Fayetteville

Caney andWoodford

WoodfordBarnett

Barnett andWoodford

Palo Duro

Green River

Monterey

McClure

Cane Creek

Lewis and Mancos

Niobrara Gammon Bakken Excello/Mulky New Albany

Quality images provided by the geoVISION service can help pinpoint reserves in the diverse shale gasplays found in the continental United States.

geoVISION Resistivity Specifications

General Specifications geoVISION675* system geoVISION825* system

Collar dimensions Nominal diameter 6.75 in 8.25 inMaximum diameter 7.75 in 9.5 inUpper head connection 51/2 FH box 65/8 in FH boxLower head connection 41/2 Reg pin 65/8 in Reg boxOperating temperature Standard configuration 300 degF [150 degC] 300 degF [150 degC] High-temperature configuration N/A N/ATool length and weight Length 10.12 ft [3.08 m] 12.72 ft [3.88 m]Weight 1,200 lbm [544.3 kg] 2,400 lbm [1,088.6 kg]

Mechanical Specifications

Dogleg severity Rotary mode 8°/100 ft 7°/100 ftSliding mode 16°/100 ft 13°/100 ftBending strength ratio (BSR) Upper connection BSR 2.10 2.44Lower connection BSR 2.68 2.56Equivalent bending stiffness 10 ft of 6.5 × 2.81 13.5 ft of 8 × 2.81Average inertia 84 in4 168 in4

Axial and rotational load Maximum weight on bit 71,000,000/L† lbf 164,000,000/L† lbfMaximum jarring load 330,000 lbf 640,000 lbfMaximum rotary torque 16,000 ft.lbf 23,000 ft.lbfHydraulics Maximum external pressure 18,000 psi 15,000 psiStandard flow range 0 to 800 galUS/min 0 to 1,200 galUS/min Pressure drop constant (C) 135,000 790,000

Measurement Performance

Resistivity Bit and ring Azimuthal button electrodeRange 0.2 to 20,000 ohm.m 0.2 to 20,000 ohm.mAccuracy

0.1 to 250 ohm.m ± 5% ± 5%250 to 500 ohm.m ± 10% ± 10%500 to 5,000 ohm.m ± 20% ± 20%

Noise floor 0.2 mS 0.2 mSResistivity response Bit Ring Deep Medium Shallow Vertical resolution 12 to 24 in 2 to 3 in 2 to 3 in 2 to 3 in 2 to 3 in Depth of investigation 12 in 7 in 5 in 3 in 1 in Resistivity environments Water-base mud Because geoVISION resistivity is a laterolog measurement, the geoVISION tool should be run

under conditions where Rxo is less than or approximately equal to Rt to ensure that the tool is sensitive to Rt when there is significant invasion.

Oil-base mud Correlation with bit resistivity only Gamma ray Range 0 to 250 gAPI Accuracy ± 7% Statistical resolution ± 3 gAPI at 100 gAPI and 100 ft/h Vertical resolution 1.5 in

† L is the distance in ft between the stabilizer above the tool and the stabilizer below it.

APPLICATIONS

� Real-time image and dipcalculation to help positionwells in the best place in the reservoir

� Real-time geostopping for coring and casing pointselection in both oil- andwater-base muds

� High-resolution imaging for fracture identification and complex interpretations

� Invasion profile analysis

� Thin bed analysis

FEATURES

� Three azimuthally focusedelectrode resistivity measurements

� High-resolution focused ring resistivity

� At-the-bit resistivity

� Azimuthal gamma ray

� High-resolution multidepthresistivity image with full coverage

� Enhanced resolutionimage processing

� Combinable with all otherSchlumberger drilling andmeasurement services

� Runnable directly above thebit for enhanced geosteering

� Resistivity measurements to 20,000 ohm.m

Resistivity imaging-while-drilling service

*Mark of Schlumberger Copyright © 2007 Schlumberger. All rights reserved. 07-DR-122

geoVISION

www.slb.com/vision

Resistivity imaging provides multipledepths of investigationfor productive drilling.