Monitoring-Modelling loop –experience from the Ketzin site

Stefan Lüth, Thomas Kempka, Alexandra Ivanova

GFZ German Research Centre for Geosciences

Combined Meeting of the IEAGHG Modelling and Monitoring NetworksEdinburgh, 5-8 July 2016

Agenda

COP21

Reservoir Modelling and Simulation

Simulated and observed Plumes

Performance criteria

Conclusion and outlook

Project designRisk

assessment

Enhancement of process

understandingForecasting

Modeling and simulation started before injection and accompany entire operation

Bielinski (2007)Kopp et al. (2008)

Frykman (2008)

Lengler et al. (2010)Chen et al. (2014)

Kempka et al. (2010)Wiese et al. (2010)

Kempka and Kühn (2013)Klein et al. (2013)Kempka et al. (2013)Kempka et al. (2014a,b)De Lucia et al. (2015)

Geological model:Norden and Frykman (2013)Kempka et al. (2013a)

Matching simulated and observed pressures –model correctly describes effective hydraulic

properties close to wells

Sleipner: simulated and observed plume areas(top layer)

Chadwick & Noy, 2015

• Shape not exactly reproduced.• Performance criteria defined to describe effective properties.• Convergence to excellent match for, e.g., plume footprint area.

Ketzin: observed and simulated plume geometries

CO2

2009 2012 2015

Seismic

Simulation

0.3

7 m

Quantifying conformity between simulation and observation with uncertainties

Performance parameters

• Geometrical parameters (effective reservoir properties):• Plume footprint area (permeability).• Maximum lateral migration (anisotropy).• Plume volume (permeability, layering, P-T).

• Direct comparison of footprints:• Similarity index (Sørensen-Dice coeffizient, reservoir model

representing „true“ heterogeneity).

AB C

S = 2C / (A + B)

Uncertainties

• „Seismic plume“ • Amplitude (or impedance) anomaly in difference data.• Affected by noise, not related to storage.• Amplitude threshold.

• „Simulated plume“• True reservoir heterogeneity unlikely to be fully described

by the model.• Distribution of CO2 partially goes into very thin layers.

--> Apply performance criteria to range of amplitude thresholdand thickness values.

Plume footprint area 2012 and 2015

2009 2012

Sim 2015

Sim 2012

Seis 2015

Seis 2012

Simulation 2015 Seismic 2015

Seismic 2012Simulation 2012

2015 vs. 2012:

Simulated plumefootprint has grown.Seismic plume footprinthas become smaller.

• Seismic observationrealistic – simulationunderestimatingdissolution…

or

• Simulation realistic –seismic observationhas a detectionissue.

Similarity index

2009 2012

2009 2012 2015

• Similarity index shows decreasing conformity from 2009 – 2012 – 2015.• Reservoir model based on pressure history matching and 2009 seismic data.• Model uncertainty increasing with plume propagating further beyond Ketzin

wells.• Dissolution and diffusion correctly described?

Conclusion & outlook

• Pressure based history matching good for describing efectivehydraulic properties if sufficient pressure observationsavailable.

• High-resolution time-lapse seismic observations and reservoirsimulations allow conformity assessment at reservoir scale.

• Effective performance criteria (e.g. footprint area) andsimilarity demonstrate matching of observations andsimulations.

• Next step forward: coupled inversion of geophysics andreservoir simulations by including performance criteria intoobjective function.

Thank you!