Completion Option 1 : Pumping Down Technique
- Guns System
- Bridge Plug System
Stimulation Stage Pump down
Foam Cemented Multi-Stage Perf and Plug
Stimulation Span 300 ft. - 500 ft.
Cluster spacing: 75 ft. – 150 ft.
Cluster Length: 6 ft. – 2 ft.
8-12 stage 3-4 days
Stage
Cluster Spacing
Cluster length
Pump down
Perf/plg
Completion Option 2 : Multi Stage Fracturing Assembly
σ H-max σ ob
Well Direction: σ h-min
- FMI: Induced Fractures - Caliper&FMI: Breackout - Sonic Logs - Microseismic
1,500 ft
After 15 Y ears
1,500 ft
After 15 Y ears
σ h-min
Effective Drainage Area
Non Effective Drainage Area
= k .0 0 0 0 m 1 ( d m tr a ) ix
0 0 1 , ft 0
re T tm a n e o t H o riz ta n l W
ll e ^ ft
3
p S c a g in 4 = 0 0 t f
f t 0
ft A r e 5 1 e Y rs a
= k .0 0 0 0 m 1 ( d m tr a ) ix
0 0 1 , ft 0
re T tm a n e o t H o riz ta n l W
ll e ^ ft
3
p S c a g in 4 = 0 0 t f
f t 0
ft A r e 5 1 e Y rs a
k = 0.0001 m d (matrix)
1,000 ft
Treatm
ent Horizontal W ell
ft^3
Spacin
g=400 ft After 15 Y ears
k = 0.0001 m d (matrix)
1,000 ft
Treatm
ent Horizontal W ell
ft^3
Spacin
g=400 ft After 15 Y ears
k
= 0. 00 0 1 m (m d at ri
x) ri at (m d m 0 1 00 0. = k
x)
The Barnett example
Stimulations
Rigless with no multi-stage downhole tools
Water fracs
Water supply with pipelines
Multiple contractors for the same service
Gas Shales – Completion
Drill-Out & Completion
Workover rigs required
Mill-Out of plugs with Coil Tubing
Packerless Production string
Clean-Out & Test
Wells gas-lifted initially
Water recovery monitored
Gas Shale: Micro-Seismic
Monitoring the hydraulic fracturing system
Vertical and lateral containment, interference, effectiveness
Optimizing well spacing
6600 6700 6800 6900 7000 7100 7200 7300 7400
Depth (ft)
Stage 2 Stage 3 Stage 4
2600 ft
1300 ft
1100 ft
7500 7600 7700 7800
-400 -200 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 3200
Distance Along Wellbore (ft) (Side View)
Lower Barnett
Optimum facilities utilization
CENTRAL COMPLEX
GAS FLOW RATE
CENTRAL COMPLEX
FIRST SATELLITE COMPLEX
GAS FLOW RATE
SECOND SATELLITE COMPLEX CENTRAL
COMPLEX TOTAL
GAS FLOW RATE
FIRST SATELLITE COMPLEX
SECOND SATELLITE COMPLEX FIRST
SATELLITE COMPLEX
SECOND SATELLITE COMPLEX
Extremely phased drilling production ramp-up much slower than conventional
Satellite plants (for “infilling” production) may never see a plateau
Even when plateau is reached, central plant production fluctuates (frequency and amplitude depending on new wells tie-ins schedule)
2000 20052005 20102010 20152015 20202020 20252025 20302030 352035
1 5 10 15 20 25 30
YEARS
2000 20052005 20102010 20152015 20202020 20252025 20302030 352035
1 5 10 15 20 25 30
YEARS
2000 20052005 20102010 20152015 20202020 20252025 20302030 352035
1 5 10 15 20 25 30
YEARS
Working by “building blocks” (“typicals”)
WELLPAD WELLPAD
about 8 wellheads (indicative)
gas/water separation, send-out manifolds
unmanned facility, remote monitoring/control NODE
NODE
simple pipelines intersection
TREATMENT HUB, TYPE I or TYPE II TREATMENT HUB, TYPE I or TYPE II
collecting production from about 15-20 wellpads schematization of a complex
to produce from ~160 wells
GAS EXPORT
WELLPAD NODE
TREATMENT HUB GAS
EXPORT
WELLPAD NODE
TREATMENT HUB
produced water storage, treatment & disposal
gas boosting (from low to mid pressure)
gas treatment to sales specifications (Hub Type II)
gas compression (from mid to high pressure) (Hub Type II) GATHERING SYSTEM ELEMENTS
GATHERING SYSTEM ELEMENTS
LINE TYPE 1 LINE TYPE 2 LINE TYPE 3
Gas lift network not highlighted (project specific)
Each line includes gas pipeline and water pipeline
Example of phasing and modularity (step 1)
0 20 40 60 80 100 120 140
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 years from OPDS start
0 5 10 15 20 25 30 35
TIE-IN NEW WELLS per YEAR GROSS GAS
56 wells active
7 wellpads active
GAS FLOWRATE WELLS per YEAR
years from OPDS start
1 2
REGIONAL HIGH PRESSURE PIPELINE
1 Hub Type II active @ 50% (1ST train) with final treatment to pipeline specification
Example of phasing and modularity (step 2)
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 years from OPDS start
0 5 10 15 20 25 30 35
TIE-IN NEW WELLS per YEAR GROSS GAS
120 wells active
15 wellpads active
GAS FLOWRATE WELLS per YEAR
years from OPDS start
1
REGIONAL HIGH PRESSURE PIPELINE
1 Hub Type II active @ 100% (1ST and 2ND train) with final treatment to pipeline specification
2
Example of phasing and modularity (step 3)
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 0 5 10 15 20 25 30 35 TIE-IN NEW WELLS per YEAR GROSS GAS
1 2
229 wells active
29 wellpads active
GAS FLOWRATE WELLS per YEAR
years from OPDS start
1 2
REGIONAL HIGH PRESSURE PIPELINE
1 Hub Type II active @ 100% (1ST and 2ND train) with final treatment to pipeline specification
1 Hub Type I active @ 50% (1ST train)
with water disposal and boosting to Hub Type II
2
Example of phasing and modularity (step 4)
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 0 5 10 15 20 25 30 35 TIE-IN NEW WELLS per YEAR GROSS GAS
1 2
314 wells active
40 wellpads active
2
GAS FLOWRATE WELLS per YEAR
years from OPDS start
1 2
REGIONAL HIGH PRESSURE PIPELINE
1 Hub Type II active @ 100% (1ST and 2ND train) with final treatment to pipeline specification
1 Hub Type I active @ 100% (1ST and 2ND train) with water disposal and boosting to Hub Type II
2
Example of phasing and modularity (step 5)
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 years from OPDS start
0 5 10 15 20 25 30 35 TIE-IN NEW WELLS per YEAR GROSS GAS
1 2
362 wells active
45 wellpads active
2
GAS FLOWRATE WELLS per YEAR
years from OPDS start
1 2
REGIONAL HIGH PRESSURE PIPELINE
1 Hub Type II active @ 100% (1ST and 2ND train) with final treatment to pipeline specification
1 Hub Type I active @ 100% (1ST and 2ND train) with water disposal and boosting to Hub Type II
2
Infill wellpads
towards Hub Type II
Gas Shale – Development
Production ramp up requires continuous drilling activity
Drilling phases are separate from
Completion/Fracking phases; the latter are executed in batches
The pace of the ramp up is function of the number of rigs utilised, of the time from spud- to-spud and the time for completion and
fracking and for connection to the gathering fracking and for connection to the gathering system
Source: Scotia Waterous
Maximisation of the recovery is function of the optimization of well spacing, horizontal
length, frac density and area accessibility
Source: Quicksilver, eni internal report
Water management
60’000 bbl fracturing water for each well
Chemical additives: can be reduced?
Flow-back water recycling?
Regulations?
water trucks
fracturing water ponds
Source: US DoE, NETL, Groundwater Protection Council, 2009
Gas Shale: Seismic and Geohazards
3D seismic is usually acquired
Main use is “defensive”
Geohazards, i.e. any geological feature that could cause a connection with an active aquifer, wrong well trajectory or well bore instability
In the framework of the technological alliance with Quicksilver, eni is testing proprietary technologies to improve the 3D seismic data quality and use
Source: Chesaapeake
Testing 3D imaging techniques
Source: eni
Gas Shale vs Wet Gas Shale vs Shale Oil
High IP (initial production rates) are usually better achieved in case of Dry Gas
production
In the intermediate zone between Gas Window and Oil Window, however, a lower gas production rate can be accompanied by an interesting NGL and Condensates
production
The Liquid content in Wet Gas Shale can
The Liquid content in Wet Gas Shale can significantly improve the economics of a project. Examples are i.a. in some areas of the Barnett, of the Marcellus and Eagle Ford shales.
In some particular cases an economical production of Oil can be achieved fron
shales (Shale Oil). The typical example are the Bakken Shales.
Shale Oil
In the Bakken shales mixed low K lithologies contained within shale packages are the main producing layers, with hydraulic fracking
allowing contribution from shales
Several other areas are proving commercially viable for oil production, even from more
purely shaly sections, e.g. Barnett Combo play
Eni joint venture
TARRANT PARKER
DENTON
Barnett Counties
operations ALLIANCE system TEXAS
Barnett Shale
HILL
BOSQUE
JOHNSON HOOD
SOMERVELLE
eni Joint Venture with Quicksilver
Barnett Shale Texas operations Alliance system
Eni Gas Shale projects
