SEAL 25 mln years BP Groningen Loppersum Eemshaven Delfzijl Geology of the Groningen Field Rien Herber Groningen Gas Field Three Geological Success Factors Permian Zechstein Sea RESERVOIR 27 mln years BP Early Permian Desert SOURCE Delft, 1st February 218 3 mln years BP Late Carboniferous Tropical Forest Modified after Kroonenberg, 28 Groningen Seismic Cross Section The Reservoir 1 km 2 km 3 km 5 km Modified after: De Jager & Visser, 217 Source: SPB Atlas, 211 1
3 N Mid Permian 24 MY Southern Permian Basin Rotliegend Paleogeography º C. Scotese In a landlocked position at some 15 to 2 North, the Netherlands was exposed to a hot and dry climate Source: Scotese, 23 Source: Geluk, 27 Rotliegend in Groningen Depositional Environments Rotliegend Environments of Deposition aeolian dune field fluvial sheet floods lateral feeder channel (incision) wind sand sheet wadi Source: Grötsch et al, 212 2
Seismic Facies Development across Groningen Field Groningen Gas Field Rotliegend Thickness Map S N 3m Seismic Expression Rotliegend Flattened on Base Zechstein Westphalian 3m Source: Grötsch et al, 212 Source (seismic): R.Romein, 217 Groningen Gasfield Net Hydrocarbon Column Height (thickness x net/gross x porosity x gas saturation) (at subsurface conditions) Rotliegend Sandstone A. In a downhole core m B. Under the microscope Porosity 23.5% Permeability 22 md 5 1 km Source: De Jager & Visser, 217 Source: Grötsch et al, 212 3
Net Hydrocarbon Column Height (at subsurface conditions) Reservoir Compaction (measured at surface in 212) 5 1 km Rotliegend Fault Patterns in NE Netherlands Source: Ligtenberg et al, 212 Groningen Field Rotliegend Fault Pattern Groningen SWNE Seismic Cross Section Focus on Deep Faulting 24. 26. 1 km 58. 6. Regional Paleo Stress Orientations (Ligtenberg et al) 3 km 5 km 7 km Source: Romein, 217 Source: Kortekaas & Jaarsma, 218 4
Groningen Field EW timesection Base Upper Northsea Dipmap Zechstein Salt Isochore Map WEST EAST 1 sec 2 sec 2 km Source: Romein, 214 2 km Source: Romein, 217 m 6. 24. 26. Groningen Field Rotliegend Fault Pattern 6 dec 17 Location of Zeerijp Tremor and its Precursors based on Moment Tensor Inversion (KNMI) 58. 8 jan 18 11 mar 17 Focus on Zeerijp Area 7 dec 16 Source: B.Dost, 218 5
The Salt Top Zechstein Salt NE Netherlands Groningen Field Source: Meijles, 21 24. A 26. Zechstein Isochore Map Groningen Gasfield NS Transect A A 1 1 5 1 15 17 thickness in meters depth in meters 2 3 Source: R.Romein, 217 A Source: R.Romein, 217 6
Defocussing in Salt and Scattering in Anhydrite Stringers ray paths simple velocity model Wavefront Simulation Tertiary 1 km 1 Chalk 2 km Zechstein salt More detailed velocity model 2 km 3 Rotliegend 4 3 km Carboniferous 5 km Modified after Kraaijpoel, 212 Source: ExxonMobil, 215 3km N Impact of 3D Scattering Difference (ba) The Shallow Soil 3km 3km (a) Flat Layer Model 3km N 3km N Source: ExxonMobil, 215 (b) Groningen 3D Earth Model 7
Huizinge Tremor, 16 th August 212 Recorded Acceleration at station Middelstum1 Site Response depending on Soil Composition V sh 1 2 m/s Acceleration (cm/sec 2 ) Horizontal X Horizontal Y Vertical 51m V sh 2 3 m/s dispersion & damping 3m Source, KNMI 212 Shallow Soil Groningen WE Cross section Winsum Woldendorp Huizinge Tremor Intensity 16 August 212 Eemshaven Delfzijl 1 km 5m Groningen Source: Meijles, RUG, 215 Source: KNMI 213 8
Soil Composition Groningen (top 2m deposited from 8 AD until today) Upsweep Effect of Shallow Soil Eemshaven Eemshaven high Amplification 23 Hz low Delfzijl Delfzijl Groningen Groningen Source: Alterra 26 Source: Tijn Berends (MSc, RUG), 214 Source: Alterra, 26 Upsweep Effect of Shallow Soil Anthropocene Dwelling Mounds Paleogeography 15 BC high Amplification 23 Hz low Tidal flats & channels peat Source: Tijn Berends, MSc RUG, 214 Density? Velocity? Fluvial deposits & salt marshes 9
Locations of Dwelling Mounds in Groningen and Friesland (from 6 AD onward) Groningen Seismic Cross Section 1 km 2 km 3 km 5 km Source: Landschapsbeheer Friesland & Groningen Modified after: De Jager & Visser, 217 Special Thanks to: Jan de Jager Clemens Visser Remco Romein 1