NWO has awarded a total of almost 9 million euros to eight innovative research projects into deep subsurface movements and processes under the Netherlands. These projects fall within the research programme DeepNL, that seeks to improve the fundamental understanding of deep subsurface dynamics that occur under the influence of human interventions. The projects concern, for example, how hot geological faults can become, ground subsidence as a source of information for subsurface processes, and predicting surface deformation.
Nine million for research into deep subsurface processes under the Netherlands
There is insufficient scientific knowledge available about the effect of human interventions deep under the ground. The programme DeepNL therefore wants to build up knowledge about deep subsurface movements and processes. With this programme, NWO is responding to the advice of the Dutch Safety Board to ensure a structural and long-term research programme into the problems related to gas extraction in the province of Groningen. Within the projects, senior researchers together with 31 new PhDs and postdocs will, over the next four years, perform laboratory experiments and fieldwork and use computer models. DeepNL is partly possible due to a financial contribution from NAM and is part of NWO's contribution to the Top Sector Energy.
Below you find the projects Utrecht University is involved in.
Main applicant: Prof J.A. Trampert, UU
Co applicants: dr K. Smetana UT, prof M.N.M. van Lieshout UT, dr H. Paulssen UU
Comprehensive monitoring and prediction of seismicity within the Groningen gas field using large scale field observations
The induced seismicity of the Groningen gas field can only be understood through the relation between gas extraction and subsurface response. To understand the dynamics of the system new approaches are required that are based on observational data. We will monitor the seismicity and determine stress changes, reservoir compaction and deformation of the overlying layers from seismic data. Advanced tools based on machine learning, model order reduction and supercomputing will be developed to model the recorded seismograms and to detect subsurface variations. Changes in earthquake risk due to changes in gas production will be assessed by stochastic modelling.
Main applicant: Prof J.D. Jansen, TUD
Co applicants: prof C.J. Spiers UU, dr A. Barnhoorn TUD, dr H. Hajibeygi TUD, dr S.J.T. Hangx UU, dr D.V. Voskov TUD
Science4Steer: a scientific basis for production and reinjection strategies to minimize induced seismicity in Dutch gas fields
What happens to the Dutch subsurface when used for the production, injection or storage of fluids? Does suddenly stopping production from a gas well in Groningen also stop earthquakes or may it provoke new ones? What are the effects of production and injection during underground gas storage? How does reservoir rock behave under fluctuating stresses? Our Science4Steer research addresses these questions with laboratory experiments and computer models to help society make better decisions. Many aspects are important in such decisions and many factors contribute. The role of science is to provide understanding how we can steer subsurface activities safely.
Main applicant: Dr A.N. Niemeijer, UU
Co applicant: dr M. Dekkers UU
Probing the micromechanics of small magnitude earthquake slip
Earthquake slip generates heat on faults which raises temperature and weaken faults. We will develop a method to measure temperature anomalies in outcrops and experimentally determine the effect of frictional heating on pore fluid pressure evolution to constrain the evolution of temperature and friction for small magnitude earthquakes. This information is necessary for the improvement of computer models of earthquakes and a better risk assessment.
Main applicant: Dr F.C. Vossepoel, TUD
Co applicants: dr Y. van Dinther UU, dr A. Niemeijer UU
InFocus: An Integrated Approach to Estimating Fault Slip Occurrence
Gas production can lead to fault slip in the subsurface, which can result in earthquakes. By combining measurements of fault slip in a laboratory with realistic physical models of fault behaviour, we can refine its properties and variables. This allows to better understand the processes at the fault’s interface. The aim is to provide probabilistic estimates of fault slip occurrence. This research will provide a decision-making tool that through considering different gas-production scenarios will help to minimize the effects of earthquakes for society.
Main applicant: Dr S.J.T. Hangx, UU
Co applicants: prof M.R. Drury UU, dr H.E. King UU, dr O. Plümper UU, dr C. Thieulot UU
A multi-scale, multi-physics framework for modelling the geomechanical response of sandstone reservoirs to pore fluid
Extraction of fluids, like natural gas, from the Earth’s crust frequently results in surface subsidence and tremors. The cause lies in reservoir compaction, driven by the increase in effective overburden stress due to decreasing reservoir fluid pressure. However, the long-term surface impact of fluid production cannot be predicted confidently. The key barrier to obtaining appropriate models is that the physical and chemical mechanisms responsible for reservoir compaction are poorly known and quantified at realistic subsurface pressure and temperature conditions. We will quantify these mechanisms causing long-term subsidence and seismicity, to enable prediction via computer modelling.
Main applicant: Prof R.F. Hanssen, TUD
Co applicants: dr F.C. Vossepoel TUD, dr E. Stouthamer UU, dr R.M.A. Govers UU
Monitoring and Modeling the Groningen Subsurface based on integrated Geodesy and Geophysics: improving the space-time dimension
Subsidence is an inconvenient consequence of exploitation of the subsurface. By the same token, it is one of the most important sources of information to understand subsurface behavior. Using satellite data and advanced subsurface models, we investigate how to optimally integrate improved observational and modelling methods to understand what lies beneath.