Marginal Field Development – Strategies and Technical Solutions

Baijayanta Ghosh

In the next 20 minutes

Marginal Field Development

Strategic Considerations

Case Studies

Schlumberger

Technical

Offerings

MARGINAL FIELD DEVELOPMENT – STRATEGIC CONSIDERATIONS

What is Marginal field?• An economic concept

– Limited profit margins – Various reasons

• geologic• geographic• technological • price & taxation related• under given economic conditions

• 7-15% ROI• Smaller fields

– Usually 3-7 years of productive live as opposed to 15-20 years for a regular oil/gas field

Strategy: Commercial Considerations• Early and Increased Cash flow

– Early first oil and fast cash flow• EPS – early first oil, reduce CAPEX, re-use

production facility• Marginal fields may be developed for its entire

life using modular and re-usable low-cost facilities

• Tanker vs. sharing existing production pipelines

– Phased development• Reduced fixed capital, phased, cluster

development, parallel continued appraisal

– Low capital costs : Suitability for short term use

• Using low-cost, reusable, modular production system

• Use of existing facility and/or sharing facility/pipes

– Rapid Development Period– Amenable to innovative financing

• Risk minimization through continuous appraisal

Strategy: Technical Considerations• Evaluation of high-level technical strategy

– Sub-sea tie-back, vertical well access, in-field processing on structure, sub-sea processing

• Drilling ERD/ Deviated / Highly deviated/Horizontal wells – Fast drilling with minimum number of casings and bit-trips– Proper Well Placement

• Completion– Intelligent Completions for proactive control – ICD/ICV– Sub-sea completion & technology/ artificial lift

• Cost-effective Stimulation• Monitoring wells, extended flow tests and continuous appraisal

– Intelligent Production systems: SMART Platform -> Process Simulator (OLGA Online)– Extended appraisal using PDG and flowrate data

• Processing the well fluids– Early Production Facility– Sharing production facilities– Sub-sea separation/ pumping / compression and metering – Floating/ Semi-sub facility / FPSO

• Transportation of the crude– Tie-back to trunk line– Shuttle and/or storage tanker

• Oil Tanker• CNG Tanker• LNG Tanker

CASE STUDIES

Case Study: Marcher Oilfield (BP)

• Reservoir– Fractured chalk overlying a salt diaper

• Phased appraisal / development• Phase-1 - Appraisal

– Early Production System: Modular 2-stage gas-oil separation, pumping and metering skid installed on Sedco 707 semi-submersible

– First oil from 2 Machar Wells within 19 weeks of project approval @ 30000BPD

– $130M revenue in 11 first months– EWT – deliverability and reserves

• Phase-2 – Seamless transition to development

– Engineering work completed parallel to Phase-1

– Flexible facility capability enabled Process Equipment Modification & set-up of water treatment/handling & injection set-up

• Production boosting through stimulation– sub-sea intervention

Cutting Risk, Boosting Cashflow & Developing Marginal Fields – Oilfield Review, Winter 1996

Case Study: C-Series Offshore Fields (ONGC)• C-Series fields

– gas bearing, shallow water (24-30m) marginal felid cluster

– Scantily appraised – geological & engineering risk

• No standalone development - tie-in• Sharing/using existing processing facility

–MH NQ Complex; 190km pipeline • Uncertainty & Risk Mitigation

– Flexible development plan to accommodate uncertainty

– Continuous appraisal – risk evaluation, production monitorign and reservoir management

• Flow Assurance – handling multiphase flow, hydrate

formation and lowering abandonment pressure

• Well Platform with minimum facility – low cost

• Phased development & continuous appraisal

– Cost reduction measures to manage risks IPTC 17085

Case Study: Qattara Depression Western Desert of Egypt (Agiba Pet. Co.)

• Reservoir: The thin sand beds are sandwiched between shale beds. Porosity is around 25 percent and permeability 5md -200 md in some locations.

• Phasing of the operations & flexibility to accommodate changes in the development plan.

– Use of early production facilities: collection of data while generating cash.

– Need for artificial lifting and pressure support through water injection can be judged

– sizing of facilities when field reserves & field production potential are estimated

• Use of geostatistical reservoir fancies description to assess risks in defining reserves.

• Applications of suitable technology that suits the particular conditions of fields.

– Use of Jet pumps– Workover rigs not required: removes a significant part

of the operating expenses and reduces deferral production.

• Sharing of facilities with nearby fields to improve the economic worth of the small reserves. MARGINAL FIELDS DEVELOPMENT IN WESTERN DESERT, EGYPT.

M.El Awady, Agiba Pet. Co. Copyright OMC 2001.

TECHNICAL OFFERINGS

Schlumberger www.slb.com Onesubsea – a Cameron & Schlumberger Company www.onesubsea.com

Early Production Facility• Fit-for-purpose EPFs• Early cash flow with only a minimum

cash outlay – EPFs and fast-track schedules

• Real-time production data – Continuous reservoir appraisal – Informed design for more-expensive

long-term facilities

• Exploitation of small reserves without permanent facility

• Flexible business models– Build—Own—Operate (equipment

rental plus operation) – Build—Own—Operate—Transfer

(equipment rental plus operation with the option to purchase)

• More than 30 years and to date has completed approximately 70 projects

Well Monitoring & Optimal Production Control - SMART Platform

• Supervision : Fields

• Measurement : Hydrocarbons

• Automation : Well Testing

• Remote Transmission : Data

• How it helps:– Better cash-flow through optimal

production • Production Optimization

• Gas Injection Optimization

• Reduction of Operating Cost

• Real Time Monitoring

– Continuous Appraisal / Reduce uncertainty - Extended well evaluation along with PDG

SMART Platform Layout

Production measurement

skid

Gas injection skid

Acquisition

software Radio Link to Process Platform

Vx® technology – Multiphase metering

• Python Port

• Detector assembly

• Measuring section• TOUT

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• Outlet pipe

• TT transmitter

• Ba-133 Source Ass’y

• U-spool piping

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Ba-133 Source to determine oil/gas/water hold-up or fluid fraction

Venturi to determine mass flow rate

Black Oil Model / Customized Fluid Model to determine fluid densities at line/stock tank conditions

Slip velocity Model to differentiate gas velocity from liquid, wherever applicable

Well Monitoring - Permanent Subsea Monitoring in Real Time

• WellWatcher Downhole Permanent Gauges

• Fiber-Optic DTS Systems• Digital Sensor Array

System • Downhole Network

System – power and telemetry

• Data Acquisition and Communication Systems

Sub-sea offerings contd.Production Systems

• Production Controls• Subsea Trees • DC System • Subsea Wellhead Systems • Subsea Manifolds • Flowline Connection Systems • MARS Multiple Application

Reinjection System • FasTrac Program

Sub-sea offerings contd.

Processing Systems• Pumps & Subsea Systems • Multiphase Compressors • Separation • Subsea Multiphase Meters

& Measurement Systems

Sub-sea offerings contd.

Services• Installation & Commissioning • Life of Field • Asset Management

Swivel & Marine Systems• Swivel Stack Systems • FPSO Turret System • LNG Transfer System• FSL Subsea Loading System • FPSO Controls

Sub-sea Artificial Lift & Drilling Solutions

Subsea Artificial Lift Systems– ESP Pod Systems– High-Pressure Gas Lift

Valves – Variable Speed Drives – Real-Time Monitoring

and Optimization Services

• LiftWatcher Real-Time Surveillance System

Drilling Solutions• Maximize drilling

performance – drilling longer footage of deviated/ ERD wells in single trip– PowerDrive Exceed,

advanced LWD

• Proper Well Placement• No Drilling Surprises

– Pore pressure modeling and drilling optimization

THANK YOU

Baijayanta Ghoshbghosh@slb.com