Utrecht University scientists DeepNL grant

On 5 July 2021, the Dutch Research Council (NWO) honoured seven new projects with a DeepNL external linkgrant. Five of the seven grants of 350,000 euros were awarded to earth scientists from Utrecht University. DeepNL is a long-term research programme into the gas extraction-related problems in Groningen, and will develop a knowledge base for, for example, geothermal energy extraction and underground CO2 and hydrogen storage.

The DeepNL projects
PhysMmax: Constraining the maximum magnitude in Groningen through 3D multi-physics, data-driven modelling
Tectonics and earthquake expert Ylona van Dinther external linkand her team will improve current estimates of the largest possible earthquake (Mmax) in Groningen. These extreme scenarios largely determine the earthquake hazard. At the moment, Mmax is determined by statistical analysis of observed earthquakes and by expert opinion, while the physical basis for this is rather limited.

In the future, this new physical framework may also be of great value in determining the earthquake risk for induced and natural earthquakes in the Netherlands and worldwide.

Dr. Ylona van Dinther
Van Dinther: “PhysMmax combines three highly advanced 3D computer models to obtain physically-constrained scenarios of Mmax, taking into account the complex underground structure and production history of the field. In the future, this new physical framework may also be of great value in determining the earthquake risk for induced and natural earthquakes in the Netherlands and worldwide. The development of an internationally groundbreaking framework that can have a direct and important contribution to society is what makes this project so exciting.”

Quantitative constraints on pre-production reservoir stresses in Groningen
Tectonophysicist Rob Govers external linkwill estimate the material stresses that prevailed in the reservoir rock of Groningen before gas production started. Pumping up gas increased these background stresses, which eventually led to earthquakes. The aim of the project is to understand the transition from thirty years of pumping without earthquakes, followed by thirty years with earthquakes. The findings may prove important for seismicity after gas production is stopped.

I expect to make a relevant contribution to answering questions about the negative effects of gas extraction in Groningen.

Dr. Rob Govers
Govers: “I am very happy with the DeepNL grant for this project, because I expect to make a relevant contribution to answering questions about the negative effects of gas extraction in Groningen. Natural stresses are caused by plate tectonics and ice ages. I will use a new type of computer model with many and somewhat uncertain forces, and validate the results with observations in areas where the stresses have not been affected by gas production.”



Above and below: the behaviour of rocks directly above and below producing gas reservoirs
Working at Utrecht University’s High Pressure & Temperature Lab, experimental rock mechanist Suzanne Hangx external linkand her team will investigate the subsidence of soft, clay-rich rock layers around gas fields. Extraction of fluids such as natural gas from deep underground often leads to subsidence and tremors. This is largely caused by compaction of the gas reservoir itself, but the rock layers directly above and below a gas field can also play a role. Many Dutch gas fields are surrounded by softer, clay-rich rock layers, which react differently to gas production than the more rigid sandstone reservoir.

Together with the other 17(!) projects within DeepNL, I really feel that as if the overall picture for Groningen is slowly becoming clear. It is fantastic to be able to contribute to this!

Dr. Suzanne Hangx
Hangx: “Our team will identify and quantify the mechanisms responsible for the slow deformation of these surrounding rock layers, in order to improve and extend risk assessment through computer modelling. I am very pleased with the opportunity to continue to contribute to the DeepNL programme with a new project. Within an earlier round of the programme, I have already secured one project as Principal Investigator, and one in collaboration with Delft University of Technology, both specifically focussing on the sandstone reservoir. With this project we will also be able to quantify the contributions of the immediate surrounding rocks, which has only been done to a limited extent so far. Together with the other 17(!) projects within DeepNL, I really feel that as if the overall picture for Groningen is slowly becoming clear. It is fantastic to be able to contribute to this!”

LabQuakeAI – Combining new experiments & AI toward earthquake prediction
Ivan Pires de Vasconcelos external linkis an expert in imaging science, waves and their interactions with materials. In collaboration with Andre Niemeijer – experimentalist & earthquake expert – he will build a novel experimental setup to that will be one-of-kind: capable of simulating laboratory earthquakes in more realistic scenarios, using high-end ultrasound to observe earthquake-related behaviour in real time.

Though earthquake prediction in real field cases is still far in the future, this exciting research will be an important milestone for us to one day more reliably predict when an earthquake may occur.

dr. Ivan Pires de Vasconcelos
Pires de Vasconcelos: “I am incredibly excited about this project, not only because it solidifies multi-disciplinary collaboration in Earth Sciences, but also because of the unique combination of state-of-the-art experiments with AI techniques to progress our understanding of the incredibly challenging problem of predicting earthquakes. Though earthquake prediction in real field cases is still far in the future, this exciting research will be an important milestone for us to one day more reliably predict when an earthquake may occur.”

Geological analysis of multi-scale faults in reservoir systems and implications for fault mechanical behaviour in the Groningen field
Gas extraction from the Groningen field leads to earthquakes, caused by slip on ancient faults. Key characteristics of these faults such as fault structure, kinematics and strength are poorly known, making earthquake hazard assessment problematic. With this project, tectonics expert Ernst Willingshofer external linkwill determine the mechanical properties of such faults through an innovative integration of geological observations in the Groningen structure with detailed (micro)structural analysis of field analogues rock physics experiments and physical analogue modelling.

We are extremely happy with the approval of our project because it allows for connecting the geologic past to the present.

Dr. Ernst Willingshofer
Willingshofer: “We are extremely happy with the approval of our project because it allows for connecting the geologic past to the present by studying the influence of pre-existing geologic structures established since Palaeozoic times on fault slip and associated seismicity related to human activities.”