Jasmine Reservoir Modelling and History Match. Zubin Jehangir, Kevin Ashton, Peter Henderson, Laura Armstrong

Transcription

1 Jasmine Reservoir Modelling and History Match Zubin Jehangir, Kevin Ashton, Peter Henderson, Laura Armstrong

2 Agenda Jasmine Field Introduction Post Production Data Acquisition Reservoir Modelling and History Match Opportunities & Future Potential Conclusions 2

3 Introduction: Jasmine Location & Stratigraphy Jade Discovered 1996 Production 2001 Judy Discovered 1985 Production 1995 Jasmine Discovered 2006 Production 2013 Primary Reservoir Joanne Sandstone Interbedded Fluvial Continental Sands Top Joanne Sand Depth (Triassic) Jasmine Field Partners: Shell & ENI High Pressure (11,500 psi) High Temperature (330 degf) 3

4 History & Production Mboe/d Field History Discovered 2006 Appraised Drilled 6 Development wells OBN 3D Seismic 2011 First Production 19th Nov 2013 Infill Drilling (2 wells) Well Intervention 2016 Jasmine Field Production All Wells km Top Joanne Sandstone Depth (Contour Interval = 100 ft) Nov-13 Nov-14 Nov-15 Nov-16 4

5 Lower Joanne Depth TVDSS (ft) Field Challenges Large hydrocarbon column (~2000 ft) with a low Kv/Kh ratio Strong differential depletion Restricted lateral connectivity Perm Jasmine GOR and Psat vs Depth GOR (Scf/stb) & Psat (Psia) Loss of reservoir quality with depth and column height Complex PVT with compositional gradient Oil-wet system/complex rel-perm High near wellbore productivity Structural complexity (seismic and sub-seismic scale faults) GOR PSAT 5

6 Post Production Data Acquisition A Received support and funding for extensive data acquisition Red lines to right of well indicate cumulative PLT production A PLT data acquisition showed better than anticipated productivity throughout the Joanne Sandstone Lower Joanne had better flow characteristics than initial anticipated based on logs and initial 3D models A A Pentland Josephine 2016 PLT blocked Restriction Joanne shallow TD Restriction HWC

7 Reservoir Modelling Pre-Production MD ft Lower Joanne originally modelled using consistently sized channel bodies throughout, with a rock-type model This, in conjunction with degrading rock quality at depth, severely impaired modelled deep contribution Model required ten-fold increase in permeability to match actual PLT Well 1 15,200 15,400 15,600 15,800 Well PLT Response Cumulative Flow % 0% 20% 40% 60% 80% 100% 16,000 16,200 16,400 16,600 Actual PLT Data Previous Model PLT match Not to Scale 16,800 7

8 New History Match Model MD ft New model has more sheet like bodies in Lower Joanne Updated model is able to match PLT Connectivity in the deep layers is the key to matching the PLT s Well 1 15,200 15,400 15,600 Well PLT Response Cumulative Flow % 0% 20% 40% 60% 80% 100% 15,800 16,000 Not to Scale 16,200 Actual PLT Data History Match Geo model Iterative process to create history match 16,400 16,600 Updated Model PLT Match Simulation 16,800 8

9 MMSCF/D BOPD Current History Match to Production Model is run on gas rate control It can effectively predict overall GOR trend and post shutdown flush production Jasmine Gas Production HM Model End 2015 History Data End ACTUALs Jasmine Oil Production HM Model End 2015 History Data End ACTUALs Flush Production Nov-13 May-14 Dec-14 Jun-15 Jan-16 Jul-16 Nov-13 May-14 Dec-14 Jun-15 Jan-16 Jul-16 9

10 Gas Rate (MMscf/d) Well Intervention Opportunity Example Oil Rate (Bbls/d) GOR (scf/stb) Interpretation of the PLT of one of the wells showed a blockage, with no production from the lower Joanne (~50% of 1800 ft column) This led to a coiled-tubing intervention to clean out the blockage and reperforate the section Result was significant additional production and well EUR SEPARATOR RATES Pre-Cleanout Performance Post-Cleanout Performance 0 0 Jun/16 Jul/16 Sep/16 Oct/16 Dec/16 Feb/17 Mar/ Without proving the lower Joanne had such potential, these well intervention activities would be difficult to justify GOR Post-Cleanout Performance 0 Jun/16 Sep/16 Dec/16 Mar/17 10

11 Future Opportunities Further well intervention opportunities Other cleanout s/reperforations under consideration (Q3 2018) Infill drilling 2018 Infill Drilling 2018 reservoir pressure (psi) Remaining infill well potential towards north A A Remaining infill well potential on flank A A 0 Crest is already being effectively drained by existing producers A Top Joanne Sandstone Depth (Contour Interval = 100 ft) A Less well-drained sections on flank and Lower Joanne 11

12 Conclusions Concern over the deliverability of Lower Joanne, pre-production PLT s fundamentally changed the way we modelled the reservoir Management and JV support of continued data acquisition was critical Added production and EUR through interventions Data has unlocked potential value, with a low cost Future infill drilling / well intervention planned Knowledge is of no value unless you put it into practice Anton Chekhov 12

13 Thanks to Our Co-venturers Jasmine co-venturers 13