Awakening the Giant: Hydraulic Fracturing Technology as an Enabler - - PowerPoint PPT Presentation
Awakening the Giant: Hydraulic Fracturing Technology as an Enabler for Greater Clair John Costaschuk, BP Clair Field Overview 75 km west of Shetland 150m water depths UKs Largest known resource 220 km2 (55,000 acres)
– 220 km2 (55,000 acres) – STOIIP c.7 billion barrels
– 500-800m of interbedded, fluvial sediments – Diagenetically altered Devonian sandstones (2-20mD) – Highly variable reservoir quality (moderate- poor) – Low API oil (24-21)
Vertical Appraisal Wells Campaign of several appraisal phases dating back to 1977 Vertical wells only drilled in first 15 years
fractured core of Clair
Drill High-Angle Wells!!!
1,000,000mD.ft
Vertical Appraisal Wells High-Angle Appraisal Wells High-Angle Appraisal Wells drilled to test Fracture Deliverability
Vertical Appraisal Wells High-Angle Appraisal Wells Development of naturally fractured areas Successful appraisal of Fracture Deliverability
field development Greater Clair (green) tested dynamically and structurally interpreted as low likelihood of natural fracturing
Phase 1 Phase 2 Phase 3
Concept Development Phases
Thickest column in Horst, 300+ m Column decreases going down-dip
100ft 200ft 300ft
0.4 0.5 0.6 0.7 0.8 0.9 1 206/8-1A 206/8-2 206/8-4 206/8-5 206/8-7 206/8-8 206/8-9 206/8-9Z 206/8-9Y 206/8-10Z 206/9-1 206/9-2 206/12-1 206/12-2 206/8-11A 206/8-11Z 206/8-12A 206/13-a2 206/8-13Z 206/8-14 206/8-15 206/8-A02 206/12a-3
Dykstra-Parsons Heterogeneity Coefficient
VI V IV III
Braided fluvial reservoirs
systems and poorly sorted, often immature, sediments
petrophysical properties
heterogeneity identified from a large variance in permeability for a given porosity
Heterogeneity Coefficients of 0.8 - 0.9 are calculated for all flow units, including the high NTG units (V/III), which indicate significant heterogeneity is present almost homogeneously.
Horizontal permeability in Unit V relatively homogeneous at an inter-well scale
across multiple well tests
average x 250ft = 5,000mD.ft No problems horizontally! Vertically??
Continuous bulk KH
Horizontal Well Core Data in Unit V
non-net
Well Test
Vertical permeability in Unit V relatively heterogeneous at a local scale
Need for fractures vertically!
Continuous bulk KH
Horizontal Well Core Data in Unit V
non-net
Well
10-2 10-1 100 101 10-2 10-1
Delta-T (hr) BI-LINE S
Bilinear Flow => finite conductivity Uplift in Flow Capacity at 100hrs of 60%
Appraisal data demonstrates mechanism to get through low Kv/Kh and contact full range
10-2 10-1 100 101 10-2 10-1
Delta-T (hr) BI-LINE
5,800mD.ft 9,500mD.ft Pre-frac Post-frac
13a-2 (1992)
Analogues
Concept still evolving – reflects view at Concept Select
Concept Select Base Case
fracturing a significant value enhancement to the project: – Considerable acceleration in rate (+100%) – Uplift in UR of 50% from unfracced
Cumulative Oil Production Oil Rate UR mmstb Well
Four stage development well due to be fracced summer 2019
What are we trying to develop?
in the Clair South development area, resulting in low average effective permeabilities (3-20mD) How are we trying to develop it?
hydraulic fracturing Reservoir Performance Prediction Hydraulic fracturing is a significant value enhancement to the project:
What are the uncertainties?
(finescale mudstones, differential depletion) and leak-off (natural fractures, faults, fracture complexity)
Clair South
– Phil Whiteley, Prue Smith, Asif Hoq, Jim Briggs, Corrado Giuliani, Alistair Roy, Colin Slater, Dave Thrasher, Martin Rylance, Laurence Murray
– John Braisby, Mensur Hodzic, Adam Beck, Kyle Metzgar, Frances Esson, Andrew Warnock, Wajahat Ali, Wiens van Zeil, James Churchill