petroleum engineering

1. M A R G I N A L O I L F I E L D S
Profitable Oil At Low Reserves : How?

2. Agenda
Case Histories For Unconventional Techniques
Unconventional Techniques For Developing Marginal Fields
Conventional Techniques For Developing Marginal Fields
Conclusion
Introduction
Challenges in marginal oil fields

3.  In 2008, Shell’s CEO, Jeroen van de Veer, announced that the era of
“easy-to-find” oil was coming to an end
1. Introduction

4. 1. Introduction: Terminology
 Commercial Fields:
 Noncommercial Fields:
 Marginal Fields:
Can be developed normally with high or normal profit
Unprofitable and can’t be developed
With parameters set at their best, development can be
profitable at their worst economically disastrous

5.  By definition a Marginal oil field is:
a field that is economically unattractive to develop and produce.
It could be a new discovery or an already producing field.
 Economical Factors that contribute in making a field marginal:
High CAPEX and OPEX
Unattractive revenue dependent on RF and production rates
Technological constraints
Government regulations and policies
Oil price
1. Introduction- Cont’d
IT’S ALL ABOUT ECONOMICS

6. Challenges in marginal oil fields

7.  The two main enemies in developing marginal fields are :
the uncertainty of DATA and TIME
1. Data Acquisition Problem (Exploration Problems)
 Uncertainty is not specific to Marginal ones
 Exploration:
 Heavy data acquisition programs is an impossible choice
 One or two discovery wells , 3D seismic for a development decision
 Appraisal drilling, long duration tests, are not applicable
2. Challenges in marginal oil fields

8. Number of wells required:
 The economy can not bear MULTIPLYING the number of wells
 They can be limited by these choices :
 Intense use of horizontal wells
 Multi-branched wells
 Hydraulic fracturing
2. Challenges in marginal oil fields

9. 2. Time :
 We have two opposite requirements:
Go fast to have a short production period
Low production for the reservoir not to be destroyed
 So, production should be optimized where:
we must reduce the velocity to insure a good recovery and have as high
a rate as possible to insure profitability
2. Challenges in marginal oil fields- Cont’d

10. 3. Production operations life:
 The uncertainty necessitates transferring costs from CAPEX TO OPEX by:
a. Using existing facilities on a contractual basis
b. Leasing as much as possible the required facilities and equipment
2. Challenges in marginal oil fields- Cont’d

11. Conventional Techniques For Developing
Marginal Fields

12. Cost optimization methods in marginal fields to ensure profitability :
1. Geology and exploration
 Re-correlation of the geologic column as more wells are drilled
 Using 3D simulation programs and available data from the nearest fields to
make a good understanding of the geology of a marginal field
3. Conventional Techniques For Developing Marginal Fields

13. 2. Drilling
 Use of PDC bits to ensure longer bit life and fewer bit runs
3. Completion and production
 Ensure wellbore production optimization
 Sub sea completion for offshore fields
3. Conventional Techniques For Developing Marginal Fields

14. 4. Stimulation
 Hydraulic fracturing for low permeable formations
 Acidizing
3. Conventional Techniques For Developing Marginal Fields

15. 5. Processing:
 Connection to the existing pipeline
 Use of excess processing capacity
 Use of idle equipment and material
 Using the in-plant test separator as a production separator
 Surface facilities debottlenecking
 Use of Floating Production Storage and Offloading (FPSO) tanker
 Direct electrical heat in offshore
3. Conventional Techniques For Developing Marginal Fields

16. Smart Solutions

17. 4.1 Smart Solutions : Cable Deployed ESP
 Use draw works unit instead of workover
rigs to handle the tubular required of
conventional ESP
 Reduce workover (Operating) costs, by
retrieving an ESP without handling tubulars

18. 4.2 Smart Solutions : Dual ESP system
Used for marginal wells to improve the production and
to provide the power and reliability demanded in high-
risk, high-cost producing wells.
Provide an in-well, cost-effective backup system that
minimizes the downtime caused by ESP failures.
Features:
Access below the ESP
Flow bypass
Automatic switching between ESPs
Parallel OR Series ESP system option

19. 4.3 Smart Solutions : Extreme overbalance perforating
 A new concept for wellbore cleaning operations
 In EOP completions, tubing pressure is
increased before the guns are fired and then
released into the wellbore with gun explosion
 Because wellbore pressure exceeds rock
yield strength, perforating initiates one or more
small fractures beyond the zone damaged by
invasion
 This stimulation obviates the need for
cleaning the perforation tunnel

20. 4.4 Smart Solutions : Horizontal Drilling
Why this technology?
 Increase sand face
 Used for thin tight formations
 Used to prevent severe coning
 Can produce with optimum velocity
required for production in marginal
oil fields

21. 4.5 Smart Solutions : Multilateral technology:
Why this technology?
 Many targets at different depth scan be
reached from a single well
 Less casing , less drilling time
 Increases production from a single well

22.  Commonly a wellbore less than 6 in. Diameter
 Simply reducing the hole and casing sizes for each hole
interval; Consequently well cost ( mainly drilling and
completion costs) fall.
 Good candidate for developing marginal fields
4.6 Smart Solutions : Slimhole technology

23. 4.7 Gas lift Using Coiled Tubing
• CT can be used to feed the field with artificial lift gas and injector water.
• The main advantages of using coiled tubing are:
1. The cost of the pipeline is much less than the normal pipelines.
2. The required time to install the line was only a small fraction of the
time required to install a butt-welded pipeline.

24. 4.8 Smart solutions: vapor extraction(VAPEX)
Thermal method used for enhancing the heavy oil or bitumen
recovery
Twice as efficient as the older cyclic steam stimulation

25. 4.9 Tiebacks
Tieback (subsea)
 is a connection between a new oil and
gas discovery and an existing
production facility, improving the
economics of marginal fields into
profitable assets.
 It decrease the overall capital
expenditure

26. 4.10 Smart solution: Radial drilling
Steps: 1) Milling : milling head , fluid
2) Jetting : Fresh water or acid ,clay inhibitors

28. 4.10 Radial drilling cont’d

29. 4.10 Radial drilling cont’d
Radial
Drilling
Hydraulic
fracture
Pressure
maintenance
techniques
Steam injection
Dual completion

30. 4.10 Radial drilling &Hydraulic fracturing
Economical challenge
Are you SURE where your FRAC is going?
Advantages:
• Directing fracture by orienting laterals
• Provide a long conduit before your fracture meets resistance
• Unwanted zones

31. 4.10 Radial drilling & secondary recovery
Pressure maintenance: Laterals are designed to
enhance conventional methods of reservoir pressure
maintenance:
1) Directed Water Flood
2) Directed CO2 Flood
3) Injection Wells

32. 4.10 HOSS (heavy oil steam system)
Integration between three
technologies: radial
drilling, steam injection
dual completion

33. 4.11 Other techniques:
SSR (self standing riser)
technology:
Used in development of Deep Water
marginal oil fields
• It enables early production
• Lower drilling time and cost
• Achieving fast first oil

34. 4.11 Other drilling techniques:
1) Offshore side tracking: wells on a platform reached economic limit
Using these wells to sidetrack marginal fields
Applied in: Dessert project
2) Underbalanced drilling: wellbore pressure < formation pressure
• Providing production testing during drilling
• Reduce formation damage
• Applied in: Indonesia
In high pour point marginal oil reservoirs

35. 4.11 Other techniques:
•Extended reach drilling:
• Enhancing production by accessing different parts of reservoir
• Common practice in many areas
• Having many challenges

36. • Hydraulic fracturing mostly used in marginal fields have several bad impacts
on shallow water sources
• High water cut off in heavy oil marginal fields requires high number of pours
which contaminate subsurface water aquifers
• Disuse of mud in radial drilling reduces formation damage
Environmental impact

37. Case histories

38. Conventional Case Studies
LOCATION DESCRIPTION SOLUTION RESULT
West Qaron
Field
High cost for a
separate
pipeline
A small connection From adjacent field
IRR changed
from -2.8% to
12%
Gazwarina
Field
High cost for a
production
facility
Use of excess processing capacity of SUCO base
Field put on
production
Zafarana
Field
Effective way
of handling
crude oil
Utilizing "The Floating Production Storage and
Offloading (FPSO) tanker"
50% cost savings
production
facilities
South Bdran
Field
Esp went down
twice
Using 3.5 inches coil tubing gas lift line to transmit the
gas from the nearest platform
Operating cost
reduced
considerably

39. Conventional Case Studies Cont.
LOCATION DESCRIPTION SOLUTION RESULT
Mengkapan
Field,
Indonesia.
high water
cut.
squeeze cementing Oil rate increased from
36 BOPD to 104 BOPD.
Umusadege,
Nigeria Field
Economically
Unattractive
Improved fiscal terms,
Reduced royalty based on a sliding scale
and lower profit tax
Investment was carried
out in this fields
Semberah
Field,
Indonesia
Difficulty in
conducting
detailed
reservoir
study
Using the in-plant test separator as a
production separator( Portable)
The integrity of the
development plan
resulted in raising oil
production from 5,000
to 12,000 BOPD

40. Unconventional Case Studies Cont.
LOCATION DESCRIPTION SOLUTION RESULT
Gemsa Field
High operating
costs for a
marginal reserve
Cable deployed ESP
Reducing
workover costs
July Field
Located in a
complex
structure area
(Up-dip attic oil
reserve)
Horizontal drilling
Development of an
estimated attic oil
reserves of about
5 MMBO
October Field
High operating
costs for a
marginal reserve
Slim-hole Technology
Reduced the
drilling cost and
saved 80% of the
cost of a
conventional
completion
Geisum Field
High operating
costs for a
marginal reserve
Convert jack-up rig to offshore platform
Operating cost is
reduced to 1.35
USD/Bbl

41. Unconventional Case Studies- Cont’d
LOCATION DESCRIPTION SOLUTION RESULT
Semberah
Field,
Indonesia
Difficulty in
conducting
detailed
reservoir study
Extreme overbalance perforating
Oil production
increased from
5,000 to 12,000
BOPD
Alberta Field,
Canada
technical
challenges
Horizontal wells, water injection, dual ESP system,
subsea tieback technology and subsea multiphase
metering.
Horizontal wells
produced 15:20
000
The Younis
Field
high operating
cost for marginal
field
use of coiled tubing
Reduce the cost of
pipe and time
needed for pipe
installation

42. Case study from Al Alamien Field
 Acid Frac :
L Bah
AR/G
M Bah
SR Pump

43. • For marginal oil fields , the principal criteria for selecting the field
development option was : technical feasibility , economic profile ,
environmental considerations
• The real challenge is not in selecting the most suitable technologies but in the
way these technologies will be managed.
• It is less the power of the weapons which will lead to victory than the art of
using them.
• The reservoir engineering responsibility of a marginal field must be given to
an engineer who ‘FEELS’ the reservoir more than to one who ‘COMPUTES’ it
Conclusion

44. References
 Technology for Developing Marginal Offshore Oilfields.
 Subsea engineering hand book.
 Leye A. Adetoba, SPE, Chevron Nigeria Ltd. The Nigerian Marginal Field Initiative:
Recent Developments. Paper SPE 163040. Presented at the Nigeria Annual International
Conference and Exhibition held in Abuja, Nigeria, 6–8 August 2012.
 Samuel HUSY - Total S.A.. Marginal Fields: Technology Enables Profitability / Marginal
Fields and their Challenges. Paper OTC 21382. Presented for presentation at the Offshore
Technology Conference held in Houston, Texas, USA, 2–5 May 2011.
 M.El Awady. MARGINAL FIELDS DEVELOPMENT IN WESTERN DESERT, EGYPT. Paper OMC
2001-27. Presented at the offshore Mediterranean and Exhibition in Ravenna, Italy ,
March 28-3-2001.

45.  A. Hassan, SPE, Gulf of Suez Petroleum Company, H. Elshahawi and K. Gad, SPE, Schlumberger Oilfield
Services. An Integrated Approach to Marginal Field Development: Case History from the Gulf of Suez.
Paper SPE 64661. Presented at the SPE International Oil & Gas Conference and Exhibition in China
held in Beijing, China, 7–10 November 2000.
 Franco Bottazzi - ENI E&P Division. Marginal Field Development Using CT Completion. Paper SPE
81706. Presented at the SPE/ICoTA Coiled Tubing Conference held in Houston, Texas, U.S.A., 8–9 April
2003.
 Oluropo Rufus Ayodele, SPE, and Samuel Frimpong, School of Mining and Petroleum Engineering,
University of Alberta, Canada. Economics of Nigerian Marginal Oil Fields. Paper SPE 81998. Presented
at the SPE Hydrocarbon Economics and Evaluation Symposium held in Dallas, Texas, U.S.A., 5–8 April
2003.
 Akinpelu, L.O, SPE, Omole O.A., SPE – University of Ibadan, Ibadan. Economics of Nigerian Marginal
Oil Fields – Identifying High Impact Variables. Paper SPE 128343. Presented at the 33rd Annual SPE
International
 Technical Conference and Exhibition in Abuja, Nigeria, August 3-5, 2009.
 John Conway, Doug Rogers, VECO, Canda. MARGINAL OIL FIELDS. Paper WPC 30180.
References Cont’d

46. Quotes
If Opportunity doesn’t
Knock, build a door.
Despite hard work, when
you are done it’s awesome.

47. Quotes Cont’d
Great days with great team.
Individually we are one drop.
Together, we are an ocean.
I had an amazing adventure and
great experience the last month,
( it was a win-win deal ).
Union with discipline is the hidden
power which creates success

48. Quotes Cont’d

49. Thank You