Presentation on theme: "Gullfaks Sør, N1/N0 og Gullfaksfeltet"— Presentation transcript:
1 Gullfaks Sør, N1/N0 og Gullfaksfeltet Tampen area
2 Gullfaks Satelitter Prosjektforslag til Gullfaks Landsbyen Bruk av multilaterale brønner på GFS Statfjord,
3 Gullfaks Sør Statfjord Formation Discovered in 1979, and part of the Gullfaks Satellites – tie in to Gullfaks field – 10 kmStatfjord formation consist of 134 m oil zone, and gas capStatfjord formationProduction start: April 1999Reservoir depth: 3300 mPressure, initial: 476 barTemp. @ 3300 m: 128 oC
4 GFS Statfjord Challenge: Complex reservoir with low recovery, goal +18% (LTP )PDO – 12.6 MSm3. Today 5.4 MSm3Increasing GOR -> reduces the oil rates.Aggressive search to increase recovery factor:EXTENDING THE LIMITS - STEP BY STEPSAdditional perforation of G-2 H and F-4 H in lower Statfjord (summer 2003)G –1 H with RMC (2003/2004)G –2 YH MLT with RMC (2004)F –2 YH MLT with RMC (2004)
5 Development of GFS Statfjord reserves drilledG-3 drilledDIACS / MLT
6 Why MLT and Remote Monitoring & Control? Poor reservoir communication and structural complexity More drainage points reduces the uncertainty.The need for more drainage point is clearly based on the STOOIP and estimated volume pr. well.A smart well and MLT well will be more robust for the geologic complexity and uncertainty in the reservoir.More drainage pointswill increase the estimated production pr wellexpose more of the reservoir:minimize the drawdownextra reservoir penetrations also allows access to reserves that otherwise would be likely to be left behind.
7 Why MLT and Remote Monitoring & Control? Production experience.Want to keep old wellboreVerify contribution from each branchOptimize, if possible, the contribution from each branch, different drawdown and GORAdjust production from different zones by surface operated valves.Clean-up of well easier with RMCMore flexibility when co-producing with the other wellsNatural gas liftLimited number of slotsAquire more data about pressure communication in the reservoir.Smart well technology is an insurance and it provides more data.Reduces the need for expensive well interventions
8 Production profile one vs. multiple branches Eclipse simulations used for justification of MLTDecision tree, evaluating well concept used.Increased production and accelerated effect.Possible to produce from areas of low productivity which otherwise would be left behind.Limited reservoir communication, need for more drainage points.Mitigate gas breakthrough.
9 Gullfaks Satelitter Innfasing av to små satelittfelt Prosjektforslag til Gullfaks Landsbyen 2006Innfasing av to små satelittfelt
10 Situation in year 2001:The SRI team also matured the Gulltopp (Dolly) discovery to PDO level in 2003Rimfaks Brent:Production start year Spring 2001: IOR possibility documented, 2 infill wells + extra gas handling capacity gives 2.1 MSm3 of extra oil.GF Sør L+M templates, prod.start Sept flowlines to GFC for GF Sør Brent gas production. Extra capacity and tie-in possibility at L/M for upsides in GF Sør Field.Prospects defined in the Brent Gp. and Statfjord Fm. in the Ole, Dole and Doffen (ODD) segments. (Later named Skinfaks.)Skinfaks/Rimfaks IOR. RES/PRO-seminar, November 2005.
11 11 variants of concept ’SRI to GFC via L/M’ (re)evaluated: DG1 team establ.Scr. ph. 1Screen.phase 2Scr. ph. 3Scr. Ph. 4Scr. Ph. 533/12-8SFeasibility study phaseDG1(BoK)DG2(BoV)DG3(BoG)PDOdel.11 variants of concept ’SRI to GFC via L/M’ (re)evaluated:- 1 or 2 templates, + 1 or 2 satellites, 1 or 2 flowlines.- Further optimising of subsea wellhead locations and subsea/pipeline cost.- Increased volumes (3.RF well, Skinfaks N1 segment, Skinfaks gas lift)Upside volumes quantified, value (risked) calculated.Selection criteria: NPV (and then IRR and NPV/CAPEX disc.)To L/MRecommendation from Project, February 2004:Optimise concept ’2SX’ (1 template, 1 satellite, 2 flowlines) further towards DG2.As we now know, concept for Gulltopp was in next screening round changed to paltform well.’Basis’ well’Upside’ wellSkinfaks/Rimfaks IOR. RES/PRO-seminar, November 2005.
21 Methods for reducing sand production A gel will act as glue between sand grainsConsolidation of loose sandSome permeability reductionPermeability reduction can be controlled (minimum reduction in water permeability)Increased sand free production rateAs a result – increased production rate with the potential of reduced water-cut
22 Oppgave - stikkord Typer gel Tilbakeproduksjon/miljø WC, perm, sonevis Lagdelte reservoarerInjeksjonsvolumØnsket plasseringFinne egnet brønn på GF