Day 11 development options formation characteristics

• Identify the method to enhance and optimize the inflow performance • Select candidates for hydraulic fracturing treatments, • Understand the design and execution of and how to • Evaluat

ADVANCED WELL STIMULATION  STRATEGIES 

Leo Roodhart  (Roodhart Energy Consultancy)6  Well Stimulation Advisor 

Gerrit Nitters  (Nitters Petroleum Consultancy Int.)6 

Well Stimulation Advisor 

HSE  

•  Identify the method to enhance and optimize the inflow performance  

•  Select candidates for hydraulic fracturing treatments,  

•  Understand the design and execution  of  and how to 

•  Evaluate pre‐treatment minifrac/data frac treatments 

•  Understand the design and execution of and  

•  Evaluate hydraulic fracturing treatments 

•  Understand and work with state of the art hydraulic fracturing  simulators  

•  Understand the environmental impact of fluids used in production  enhancement treatments 

3

Par∃cipants Introduc∃on  Cases you would like to present 

Introduc:on 

!  Day 1 

!  Day  2     

!  Day 3 

!  Day 4 

!  Day 5 

Par:cipant Cases 

Some Development op:ons 

!  Vertical well (open hole, cased and perforated etc.) 

!  Horizontal hole (bare foot, slotted liner, C&P) 

!  Multi‐Laterals 

!  (Multiple) Fractured vertical well 

!  (Multiple) Fractured Horizontal well 

!  Fractured Multi‐Laterals 

!  Snake well 

!  Cork screw well 

7

Reservoir Characterisa:on 

9

Reservoir

Characterization

Thick and

Homogeneous

No gas cap

or aquifer

Gas  water 

Thick and

Homogeneous

With gas cap

and aquifer

Layered

Laminated

Naturally fractured

Vertical well

slanted well horizontal well

Fractured horizontal well

hydrofracced well

Well path

Parallel horizontal wells preferred

kv/kh < 0.1 kv/kh > 0.1

Prop Natural fractures

Vertical well

slanted well

horizontal well

Fractured horizontal well

hydrofracced well

Well path

Reservoir

Characterization

Naturally fractured

Under waterflood

Shale gas

Heavy oil

Tight carbonates

Frac water injectors

In water injectors

Plug natural fractures

Short closely spaced parallel wells normal to fractures

Acid fingering

Propped fracture

Coal Reservoir vs Conven∃onal Petroleum Traps  

CBM: 

•  Laterally extensive coal seams 

•  Gas produced in coalifica:on process 

and adsorbed onto coal surfaces 

•  Limited communica:on between wells 

•  Water usually fills pore/fracture space 

•  Water produc:on then gas 

•  Gas is always dry 

Conven:onal: 

¥  Structurally trapped by seal 

¥  Hydrocarbon presence due to  buoyancy 

¥  Gas compressed into pore space 

!  The main objec:ve is to connect up with and enlarge an already exis:ng fracture 

network 

!  Process similar to that used in conven:onal gas wells 

!  The hydraulic fracture may extend from the target forma:on into a USDW* 

!  The fracture may connect through natural fracture systems to permeable forma:ons,  poten:ally entering a USDW*  

!  Fracture behavior through coal and other geological strata depends on site‐specific 

factors such as the following: 

!  Physical proper:es, types, thicknesses, and depths of the coalbeds and the surrounding 

forma:ons 

!  Presence of exis:ng natural fracture systems and their orienta:on in the coalbeds and 

surrounding forma:ons 

!  Amount and distribu:on of stress (i.e., in‐situ stress), and the stress contrasts between 

the targeted coalbeds and surrounding forma:ons 

!  Hydraulic fracture s:mula:on design 

*Underground Source of Drinking Water

Fracture s∃mula∃on 

fraccing?) 

Horizontal Wells 

increasing costs for clean out  

the exis:ng fracture network 

system  

beyond the propped sec:on of 

hydraulically induced fractures 

propped por:ons of induced 

or enlarged fractures.  

Oyler, 1987 

σ

Horizontal wells vs fracturing 

oriented normal to the prevailing tensional stress 

regime 

¥ Matrix acidising

¥ Microbial stimulation

¥ Explosive fracturing including the use of propellants, "Radialfrac"

¥ Electrical heating

17

¥ Matrix acidising

¥ Acid washes

¥ Chemical flushes with surfactants, solvents, mutual solvents, etc

¥ Microbial stimulation

¥ Hydraulic fracturing Ð from frac&packs to massive hydraulic fracturing

¥ Explosive fracturing including the use of propellants, "Radialfrac"

¥ Acid-fracturing including propped acid fracturing,

¥ Closed Fracture Acidising (CFA)‏

¥ Electrical heating

IT’S ALL ABOUT   IMPROVING  

THE  INFLOW PERFORMANCE 

19

ALL ABOUT CONNECTIVITY!