Weatherford's Clarion™ Optical In-Well Seismic System

Quick Links to Information Below

• Overview of the Optical In-Well Seismic System
• Clarion Optical Seismic Accelerometer
• Clarion Optical Seismic Instrumentation
• Clarion Seismic Sensing Station and Deployment System

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• Clarion Optical Seismic Accelerometer
• Clarion Optical Seismic Instrumentation
• Clarion Seismic Sensing Station and Deployment System

Overview of the Clarion Fiber Optic In-well Seismic System

Clarion™ is an all-optical seismic sensing system that is installed during the completion phase and remains in place in the wellbore throughout the life of the well. This “always on” high-quality system enables production optimization and enhanced reservoir management by making high-resolution (Clear) and on-demand (Now) reservoir imaging possible through the use of high performance optical instrumentation and miniature optical sensors. Clarion was specifically designed for hostile wellbore environments.

The system enables reliable permanent, in-well seismic applications including both active and passive monitoring. Clarion’s sensors decrease uncertainty by providing consistent, unchanging reference points in the subsurface and eliminate repeatability errors that frequently result from redeployment of temporary sensors. The optical seismic sensors achieve high sensitivity, high bandwidth and enormous dynamic range without the need for complex downhole signal conditioning, amplification and filtering typically required in most electronic sensor arrays.

Onshore and offshore systems are available for safe and easy deployment. Clarion readily combines with intelligent well components in most wellbore completions, from the simple to the complex.

Clarion Optical Seismic Accelerometer

Weatherford's Clarion optical accelerometer enables reliable, high-sensitivity single- or multi-component, permanent in-well seismic applications. This rugged, fit-for-purpose miniature opto-mechanical device delivers high performance for long-term deployment in hostile well environments and is suitable for vertical, deviated, or horizontal wells. The state-of-the-art optical sensors are compatible with Clarion seismic instrumentation and can be multiplexed to form in-well arrays without the use of downhole electronics.

Applications for the Clarion Optical Seismic Accelerometer

• High-sensitivity single- or multi-component, permanent in-well seismic applications
• Time-lapse vertical seismic profiling (VSP)
• Calibration of 4D surface seismic surveys
• Continuous seismic monitoring (microseismic monitoring, hydraulic fracture mapping, seismic while drilling, and vibration monitoring)
• Cross-well seismic profiling
• High-temperature/high-pressure (HTHP) wells
• Vertical, deviated, or horizontal wells

Clarion Optical Seismic Accelerometer Features, Advantages, and Benefits

• Miniature in-axis (z) and cross-axis (x/y) sensors and slim packaging enable installation of the accelerometer in tight annular spaces. This advantage ensures long-term operation at high pressures and temperatures without constraining other completion objectives.
• As an opto-mechanical device, the accelerometer is extremely rugged and reliable, capable of withstanding the high shock and vibration environments related to transportation and installation into wellbores.
• Requiring no downhole electronics, the accelerometer can operate long term in hostile well environments, such as high temperatures and high continuous operating pressures.
• Optical in-well sensors are electrically passive, eliminating the risk of interference with other electric- or magnetic-signal sources and ensuring the integrity of seismic data.
• Single-axis (1-C) or triaxial (3-C) configurations, with high in-axis sensitivity and low off-axis sensitivity, offer high vector fidelity for precise directional accuracy and wavefield discrimination.
• Omni-directional tilt is ideal for vertical, deviated, or horizontal wells.
• Large, dynamic range with flat broadband response offers excellent seismic fidelity, covering a wide range of in-well seismic applications.

Specifications of the Clarion Optical Seismic Accelerometer

Bandwidth	1 Hz to 800 kHz
Sensor configuration	Single-axis (1-C) or orthogonal, tri axial (3-C)
Cross-axis sensitivity	1% (-40 dB) typical
Max operating temperature	347°F (175°C)
Max operating pressure	14,500 psi (1000 bar)
Dimensions	Outer diameter: 0.95 in. (24.2 mm)
	Length: 10.55 in. (268 mm)
Vibration	15 Grms random (Navmat P9492 profile)
Shock	45G peak, 3 ms half sine

Clarion Optical Seismic Instrumentation

Weatherford's Clarion seismic system is an advanced, multi-channel optical sensing system that enables reliable, permanent in-well seismic applications. The instrumentation is compatible with the Clarion optical seismic accelerometer and combines state-of-the-art optical multiplexing with high-performance seismic recording and flexible interfacing to most conventional seismic acquisition systems. The instrumentation is located at the surface and contains all the electronics for the well site optical seismic system.

Applications for the Clarion Optical Seismic Instrumentation

• Providing permanent seismic monitoring of onshore and offshore wells
• Providing a link between surface seismic and well information
• Obtaining detailed time-lapse reservoir imaging near the well to track fluid movement and help locate bypassed hydrocarbons
• Imaging thermal fronts and re-injecting waste products, such as carbon dioxide
• Calibrating time-lapse (4D) surface seismic response to better process and understand the data
• Continuously monitoring stress changes in the reservoir to help delineate faults and understand flow paths
• Monitoring compaction that can induce well or casing damage Instrumentation
• Monitoring hydraulic fracturing and stimulation to determine fracture growth during operations

Clarion Optical Seismic Instrumentation Features, Advantages, and Benefits

• Use of Clarion optical seismic instrumentation reduces uncertainties and risk in exploration and production.
• Uniquely packaged, surface-installed, opto-electronic system with multi-wavelength laser source, combined with all-passive fiber Bragg grating (FBG)-based interferometric in-well sensors, enables high-performance demodulation of multiple in-well seismic signals.
• Broadband, wide dynamic range, and low distortion enable high-fidelity seismic data acquisition, covering a wide range of in-well seismic applications. This level of sensitivity contributes to better-informed reservoir management decisions.
• Surface instrumentation accommodates up to 32 optical channels, plus 4 auxiliary reference channels, for pseudo-continuous recording (no inter-record gap); precise time synchronization and accuracy; and storage of simultaneous in-well pressure/temperature (P/T) data in the digital record header. These advantages facilitate post-processing of integrated sensor data.
• Continuous analog data output interfaces to most conventional seismic recording systems for seamless data handoff to third parties.
• Network-capable Windows® PC-based control software, built-in noise monitoring, and data- display functions enable local and remote system operation, control, data quality control, and data access for operational flexibility, efficiency, and data sharing.
• Industry-standard 19-in. (483-mm) rack-mount portable or fixed cabinet accommodates temporary or permanently installed configurations for flexibility and ease of installation—onshore or offshore—and easy integration into existing control-room facilities or rugged use in temporary locations.
• Complex, multi-channel electronic hardware and software are surface based, not exposed to the harsh wellbore environment, so that system components and performance do not degrade over time, ensuring life-of-field reliability and on-demand data acquisition.

Specifications of the Clarion Optical Seismic Instrumentation

System Performance
Bandwidth	1 Hz to 1.4 kHz
Number of optical channels	Up to 32, 8 per fiber
Number of analog input auxiliary channels	4
Dynamic range	129 dB at 10Hz, 1mS sampling (digital output)
Distortion	0.1% (–60 dB) typical
Interchannel crossfeed	1% (–40 dB) typical
Noise-equivalent acceleration	200nG rms / √Hz typical, 10Hz to max BW
Analog data output	Continuous differential or single-ended
Analog output sensitivity	Scalable from instrument
Accelerometer	0.2 to 200 V/G
Digital data output
Data format	SEG-2 with optional P/T data combined
Sample interval	1/4, 1/2, 1 and 2 mS
Maximum record length*	197 sec at 1mS sampling, 16 ch
	113 sec at 1/2 mS sampling, 8 ch
Maximum wellpath length	19,686 ft (6,000 m) typical
Maximum offset to wellhead	18.6 mi (30 km) typical without amplification

*Dependent on number of channels and sample interval

Instrumentation
Standard configurations	19-in. (483-mm) rack-mount portable enclosures or fixed cabinet
Optional features	UPS, mass storage, remote access via modem or Ethernet LAN/WAN, direct interface to Weatherford Reservoir Monitoring system P/T data, GPS synchronization
Power	<600 W at 100 to 240 VAC, 50 to 60 Hz, single phase
Operating temperature	32° to 104°F (0° to 40°C)
Storage temperature	–4° to 158°F (–20° to 70°C)
Space Requirements*
Height	57.9 in. (147 cm)
Width	21.3 in. (54 cm)
Depth	34.3 in. (87 cm)
Weight	320 lb (145 kg)

*As packaged in 19-in. rack-mount, fixed cabinet

Clarion Optical Seismic Instrumentation Sample Configuration

Clarion Seismic Sensing Station and Deployment System

Weatherford's Clarion seismic sensing station and deployment system enables safe and easy multi-station seismic array installations on tubing or casing. For production, injection, and monitor wells, it allows ready integration of seismic sensing stations into even the most complex well completions. The unique design of the sensing station enables high-performance, multi-component, in-well seismic sensing and substantially decouples from production tubing noise, allowing a broad range of permanent in-well seismic applications.

Applications for the Clarion Seismic Sensing Station and Deployment System

• Permanent in-well seismic applications
• Outside-casing applications
• Production tubing-conveyed applications
• Dedicated boreholes
• Onshore or offshore wells
• Production or injection wells
• Vertical, deviated and horizontal wells

Clarion Seismic Sensing Station and Deployment System Features, Advantages, and Benefits

Seismic Sensing Station

• Sensing station consists of a ruggedized sensor carrier, used to house and protect optical sensors, and a threaded sensor mandrel or clamp-on device for tubing or casing conveyance.
• Sensing station design supports single- and multi component sensor configurations and multi-station arrays for permanent in-well seismic applications, allowing array customization to suit the application.
• Active sensor coupling mechanism provides optimal casing contact and substantially decouples from tubing noise in production and injection wells.
• Reliable release mechanism enables safe and easy installation and allows sensor coupling at desired well depth.
• Streamlined, low-profile mandrel is available in threaded or clamp-on style to suit most tubing sizes, threads, and metallurgies.
• Easy incorporation of sensing stations in the completion string reduces the risk of hang-up during deployment. Low deployment risk minimizes the effect on the completion design and architecture and facilitates integration with other intelligent well equipment.
• Sensor carrier is secured against axial and rotational movement, with no protrusions during run-in-hole, protecting the station against damage during installation.
• Sufficient room for cable and fluid bypass allows combination with other in-well control and monitoring systems.
• Adjustability for linear and rotational fit during tubing makeup provides easy, timesaving multi-station installation.

Seismic Array Deployment System

• Deployment system has multi-station capability and detachable array drums to handle arrays of up to 16 stations, up to 3,281 ft (1,000 m), and of varying lengths and spacing, providing operational efficiency and flexibility.
• A minimal footprint, transport protection bars, fork and sling lift options, and lift certification (DNV 2.7-1 approved) make the deployment system transportable for simplified logistics.
• Tieback points enable the deployment system to be secured to the rig floor for controlled rotation during deployment.

Sensor Carrier	Clamp-on Sensing Station

Specifications of the Clarion Seismic Sensing Station and Deployment System

Seismic Sensing Station
Deployment Methods	Approximate Minimum Station Spacing1 (ft/ m )	Tubing Diameter (in.)	Minimum Casing Diameter2 (in.)
	3.00 9.84	2-7/8	6-5/8
Production tubing		3-1/2	7
Outside casing		4-1/2	7-5/8
Dedicated boreholes		5-1/2	9-5/8
		7	9-5/8

¹ Dependent on deployment method
² Dependent on casing weight and station spacing. Other tubing/casing combinations can be evaluated on request.

Seismic Array Deployment System
Height (in./ mm )	105.2	2,673
Width (in./ mm )	53.2	1,350
Length (in./ mm )	94.5	2,400
Weight (lb/ kg )	3,300	1,500
Number of sensor stations per drum	1 to 16
Approximate maximum array length (ft/m )	3,281	1,000

Seismic Array Deployment System	Seismic Mandrel