PhD: Experimentation on Fluid-injection Induced Seismicity in Geothermal Systems

The Department of Earth Sciences is looking for a highly motivated candidate for a PhD position at its High Pressure and Temperature Laboratory (HPT), run by the Experimental Rock.

Your job

Geothermal energy, as a sustainable source with a small land footprint, is increasingly playing a crucial role in the energy transition. In the Netherlands and Europe, there is growing interest in tapping into deep fractured reservoirs to exploit high enthalpy geothermal resources.

Sustainable geothermal operations in deep fractured reservoirs require sustained reservoir circulation, thermal longevity, and minimal seismic risk, all of which are closely linked to the connectivity of the fracture system. However, the high pressure resulting from re-injected fluid can cause fracture slip, significantly altering the connectivity and hydraulic conductivity of the fracture systems, potentially leading to induced seismicity. To ensure sustainable geothermal operations, it is essential to understand how fractures behave under in-situ geothermal conditions, how they impact the connectivity and hydraulic properties of fracture systems, and how to mitigate seismogenic fracture slip. This PhD project is part of the NWO-funded GeoFirst project, which aims to advance sustainable geothermal exploitation and enhance seismic hazard management. This PhD project will involve close collaboration with geothermal energy operators, research and monitoring institutes, and geothermal industry associations.

Within this PhD project, you will perform rock mechanical and frictional experiments to characterise mechanical, frictional and hydrological properties of rock fractures in representative geothermal environments. You will also investigate fluid injection-induced fracture slip behaviour, and identify key controlling parameters with the support of analytical techniques. This will provide the foundation for developing friction-stability-permeability relationships for use in numerical modelling within a companion PhD candidate. Through collaborative experimental and numerical efforts, you will contribute to the development of a sustainable geothermal operation strategy. Throughout the project, you will regularly interact with the other consortium partners and present your results to a broader audience.

A personalised training programme will be set up, reflecting your training needs and career objectives. About 20% of your time will be dedicated to this training component, which includes following courses/workshops as well as training on the job in assisting in the Bachelor’s and Master’s programmes of the department at Utrecht University.

Your qualities

We are looking for a candidate in experimentation on fluid-injection induced seismicity in geothermal systems. You must have completed your MSc degree in Geomechanics, Hydrogeology, Geological engineering, Civil Engineering, Reservoir Engineering, or a related discipline by the time the position starts. Preferably, you will also have:

• experience or strong interest in rock mechanical experiments, or high-pressure and/or high-temperature laboratory experiments;
• experience or strong interest in analytical analyses (e.g., microstructural analyses, SEM-EDX, fluid chemistry);
• strong quantitative and data analysis skills;
• the ability to work independently and as part of a team in a multidisciplinary research environment;
• enthusiasm for geo-energy and applications relevant to the sustainable use of the subsurface; and
• excellent communication and interpersonal skills.

Due to the international character of our research, good command of spoken and written English is essential. We highly encourage applicants from all members of our community and of diverse backgrounds to join us.

Our offer

We offer:

• a position for one year, with an extension to a total of four years upon a successful assessment in the first year, and with the specific intent that it results in a doctorate within this period;
• a working week of 38 hours and a gross monthly salary between €2,901 and €3,707 in the case of full-time employment (salary scale P under the Collective Labour Agreement for Dutch Universities (CAO NU));
• 8% holiday pay and 8.3% year-end bonus;
• a pension scheme, partially paid parental leave and flexible terms of employment based on the CAO NU.