Subsurface Technical Report Dynamic Reservoir Modelling of Waddenzee Fields for Subsidence Meet & Regel 2016 Date: February, 2017 Document Number: EP201703201178 NEDERLANDSE AARDOLIE MAATSCHAPPIJ B.V. ASSEN Waddenzee Reservoir Modelling EP TABLE OF CONTENTS 1 KORTE SAMENVATTING (NL) ...................................................................................................... 4 2 SUMMARY ...................................................................................................................................... 5 2.1 INTRODUCTION............................................................................................................................ 5 2.2 MODEL OBJECTIVE AND APPROACH .............................................................................................. 5 2.3 MAIN CHANGES COMPARED TO M&R2015 .................................................................................... 7 2.4 M&R2016 CONCLUSION ............................................................................................................. 7 3 INTRODUCTION ............................................................................................................................. 9 4 MODEL DESCRIPTION & OVERVIEW ........................................................................................ 10 4.1 GEOLOGICAL OVERVIEW ............................................................................................................ 10 4.1.1 Depositional model .......................................................................................................... 10 4.1.2 Porosity, permeability and thickness trends .................................................................... 11 4.1.3 Slochteren reservoir units ................................................................................................ 11 4.2 MODEL INPUT............................................................................................................................ 12 4.2.1 Rock compressibility ........................................................................................................ 12 4.2.2 Hydrocarbon volumes in place ........................................................................................ 12 4.2.3 Absolute Permeability ...................................................................................................... 13 4.2.4 Capillary pressure ........................................................................................................... 15 4.2.5 PVT properties................................................................................................................. 15 4.2.6 Initialisation ...................................................................................................................... 16 4.2.7 Wells ................................................................................................................................ 16 4.3 HISTORY MATCHING DATA .......................................................................................................... 17 4.3.1 Historical production ........................................................................................................ 17 4.3.2 Bottom-hole pressure measurements ............................................................................. 17 4.3.3 Production logging data (PLT) ......................................................................................... 18 4.3.4 Pulsed neutron log data .................................................................................................. 18 4.3.5 Water production ............................................................................................................. 18 4.3.6 Tubing head pressure data ............................................................................................. 19 4.4 AQUIFER MOBILITY .................................................................................................................... 19 4.5 UPSCALING ............................................................................................................................... 21 4.6 DEFINING SUBSURFACE REALISATIONS ....................................................................................... 21 4.6.1 Pre-M&R2014 method ..................................................................................................... 21 4.6.2 M&R 2014 method. ......................................................................................................... 22 4.6.3 M&R 2015-2016 method. ................................................................................................ 22 4.7 FORECASTING ........................................................................................................................... 23 4.8 TRANSLATION INTO SUBSIDENCE REALISATIONS .......................................................................... 24 5 UNCERTAINTY MANAGEMENT .................................................................................................. 25 5.1 UNCERTAINTIES ........................................................................................................................ 25 5.1.1 GIIP ................................................................................................................................. 25 5.1.2 Absolute permeability ...................................................................................................... 26 5.1.3 Relative permeability ....................................................................................................... 26 5.1.4 Vertical permeability ........................................................................................................ 27 5.1.5 Vertical heterogeneity ...................................................................................................... 28 5.1.6 Faulting ............................................................................................................................ 28 5.1.7 Water encroachment behaviour ...................................................................................... 28 5.2 ASSISTED HISTORY MATCHING WORKFLOW ................................................................................. 28 6 DYNAMIC MODELLING................................................................................................................ 29 6.1 FIELD MODELS AND HISTORY MATCHING ..................................................................................... 29 6.1.1 Anjum .............................................................................................................................. 29 6.1.2 Ezumazijl ......................................................................................................................... 35 6.1.3 Lauwersoog Central ........................................................................................................ 41 6.1.4 Lauwersoog-Oost ............................................................................................................ 45 6.1.5 Lauwersoog West ............................................................................................................ 50 6.1.6 Metslawier ....................................................................................................................... 56 6.1.7 Moddergat ....................................................................................................................... 64 Page 2 of 96 Waddenzee Reservoir Modelling EP 6.1.8 Nes .................................................................................................................................. 69 6.1.9 Vierhuizen ........................................................................................................................ 80 6.2 FORECASTING ........................................................................................................................... 83 6.2.1 Forecasting Assumptions ................................................................................................ 83 6.2.2 Forecasting results .......................................................................................................... 83 6.2.3 Subsidence scenarios ..................................................................................................... 88 6.2.4 General forecasting conclusion ....................................................................................... 89 REFERENCES ...................................................................................................................................... 91 FIGURES .............................................................................................................................................. 92 TABLES ................................................................................................................................................ 95 APPENDIX A: IMPOSED FORECASTS BY WELL. ............................................................................ 96 Page 3 of 96 Waddenzee Reservoir Modelling EP 1 KORTE SAMENVATTING (NL) Dit modellering rapport bevat een gedetailleerde beschrijving van de geologische computermodellen en numerieke rekenmodellen die gebruikt zijn voor het onderzoeken van het gedrag van de gasvelden rond de Waddenzee. De druk in een gasveld daalt door gasproductie. De modellen in dit rapport maken prognoses van deze veranderende druk in de zandlagen op 3000m onder het aardoppervlak. Het rapport beschrijft de prognoses op basis van de