Utrecht University, Faculty of Geosciences, Department of Earth Sciences

Utrecht University’s Faculty of Geosciences studies the Earth: from the Earth’s core to its surface, including man’s spatial and material utilisation of the Earth – always with a focus on sustainability and innovation. With a population of 3,400 students (BSc and MSc) and 720 staff, the Faculty is a strong and challenging organisation. The Faculty is organised in four Departments: Earth Sciences, Physical Geography, Sustainable Development, and Human Geography & Spatial Planning.

The Department of Earth Sciences conducts teaching and research across the full range of the solid Earth and environmental Earth sciences, with activities in almost all areas of geology, geochemistry, geophysics, biogeology and hydrogeology. Our key research themes are Earth & Planetary Processes, Sustainable Use of the Subsurface, Planetary Health & Environment, and Climate & Life.The department hosts a highly international tenured staff of over 50 scientists and more than 110 PhD students and postdoctoral researchers. We house or have access to a wide variety of world-class laboratories, among which are UU’s Electron Microscopy Centre, the Geolab, and the Earth Simulation Lab. We also have excellent High- Performance Computing facilities.

About Utrecht
Utrecht is the fourth largest city in the Netherlands with a population of nearly 360,000 and forms a hub in the middle of the country. Its historical city centre and its modern central station can easily be reached from our campus in Utrecht Science Park by public transport or by a 15-minute bicycle ride. Utrecht boasts beautiful canals with extraordinary wharf cellars housing cafés and terraces by the water, as well as a broad variety of shops and boutiques.

Homepage: https://www.uu.nl/geo/aw

The Department of Earth Sciences is looking for a highly motivated postdoctoral researcher (up to four years) and PhD candidate (four years) to model and image the earthquake system in subduction zones.

You will be part of a multi-disciplinary team largely funded by a 2.5-million-euro ERC Consolidator grant “RESET: mega-thRust Earthquake System Theory” awarded to Dr Ylona van Dinther.

RESET aims to drastically improve inferences of future earthquake locations, sizes, and maybe even timing. Significant advances will come from integrating more satellite observations and novel system-based physics. RESET will introduce an Earthquake System concept and model, which unifies motions across the subduction interface, tectonic plates, and mantle bridging space, time and methodological inference scales. This will allow us to infer fault motions and system processes from surface velocities observed with satellites. Currently, that is done by inverting horizontal velocities either before, during, or after earthquakes. Together we will add the inversion of vertical velocities, and assimilate observations before, during and after earthquakes.

Methodologies build forth on our groups advances, which also predicted the newly observed vertical velocities. To integrate unprecedented amounts of data in a visco-elasto-plastic Earth-like system we will leverage the latest High-Performance-Computing research for forward and inverse modelling on Graphical Processing Units (GPU’s). Your multi-disciplinary efforts will be critical, because estimates based on new vertical velocities suggest current depth estimates for future earthquakes could be significantly off. This could make the difference between anticipated shock and world-class disaster for up to 3 billion people living close to subduction zones and coastlines. Moreover, your work will contribute to developing a community code that will allow many to unlock discoveries through applications to more processes, observations, and regions.

Currently, we seek one PhD candidate and one postdoctoral researcher. The focus and extend of each position will be tailored to your expertise’s and interests, as we intend to build a strong team based on the best candidates. Hence, we encourage candidates from a wide range of backgrounds to apply. There are two main focus areas and the decision to appoint either the PhD or the postdoc to each position, will be made based on the potential candidates. Therefore, in your application, we welcome you to express and motivate your specific interests and preferences.

One position focuses on forward modelling of earthquake sequences in self-consistent lithosphere-mantle-subduction fault systems. You will develop massively parallel 2D and 3D Earthquake System models based on pseudo-transient solvers running on GPU’s. These High-Performance-Computing methods are being developed within GPU4GEO using Julia for applications ranging from geodynamics to glaciology. You will develop the earthquake modelling branch by implementing our invariant rate-and-state friction formulation and developing a setup for subduction zones. You will run both cross-scale and observationally constrained regional simulations with unmatched realism in geometry and rheology. You will focus on simulating Chilean, Japanese, and Cascadian margins to understand how which fault slip, plate tectonic and mantle processes govern vertical velocities before, during, and after earthquakes as well as other geodetic observations. You will build the foundations to integrate these multi-scale processes into a dynamic concept of plate tectonics.

The second position will focus on inverse modelling in form of Bayesian inference. In this position you will develop massively parallel, adjoint-based inverse methods to infer fault motions and material parameters adopting Earthquake System consistency. You will retrieve the adjoint gradients for a visco-elasto-plastic rheology through leveraging GPU4GEO’s automatic differentiation tools. In synthetic tests you will develop, verify and optimize novel inversion procedures to exploit their multi-parameter and multi-observational potential. You will apply these methods to invert horizontal and vertical surface velocities measured by satellites before, during and/or after earthquakes. This will allow you to infer fault motions that e.g., indicate future earthquake locations. A non-linear inversion will also allow you to infer viscous, elastic and potentially brittle/plastic parameters. You will study the subduction zones in Japan, Chile, North-Western United States and the Caribbean Antilles.

Both positions will be hosted in the Earth Simulation Laboratory, one of the largest experimental laboratories to study the physical behaviour of the Earth. From under Ylona van Dinther’s lead, you will interact with colleagues with different expertises, including Seismology, Experimental Rock Deformation (André Niemeijer), Tectonophysics, and Mantle Dynamics. You will work as part of the GPU4GEO community with e.g., Ludovic Räss (Lausanne, ETH Zürich) and Boris Kaus (Mainz), and in close collaboration with our permanent Earth Science Numerical Support team.

As a post-doctoral researcher, you may be given the opportunity to contribute to the supervision of PhD candidates and BSc/MSc student graduation projects, in line with your research area. This post-doctoral position is intended to last for four years and extension to this full period will be evaluated after one year.

As a PhD candidate, you will become an independent scientist with a doctoral degree in four years. We will set up a personalised PhD training programme, 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.

Qualifications
We are looking for two highly motivated and ambitious candidates to model and infer earthquakes and processes in the earthquake system in subduction zones.

The postdoc must hold a PhD degree in Earth Sciences, Computer Sciences, Physics, Mathematics, Engineering, or a related discipline by the time the position starts.

The PhD candidate must hold a MSc degree in Earth Sciences, Computer Sciences, Physics, Mathematics, Engineering, or a related discipline by the time the position starts.

Preferably, you also have:

• strong computational skills or interests, where experience with code development, High-Performance Computing, continuum-based numerical methods or adjoint-based inversions is considered an advantage;
• experience with, or a strong interests in, studying earthquakes or geodynamics;
• the ability to work independently as well as part of a multidisciplinary team;
• strong scientific writing, presenting and communication 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.

Terms of employment
For the postdoctoral researcher we offer:

• a position for 12 months, with an extension of up to four years after positive evaluation;
• a working week of 32-40 hours;
• a gross monthly salary between €3,879 and €5,331 in the case of full-time employment (salary scale 10 under the Collective Labour Agreement for Dutch Universities (CAO NU)).

For the PhD candidate we offer:

• a position for 12 months, 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;
• a gross monthly salary between €2,901 and €3,707 (salary scale P under the Collective Labour Agreement for Dutch Universities (CAO NU)).

For both positions we offer:

• 8% holiday bonus and 8.3% end-of-year bonus;
• a pension scheme, partially paid parental leave, and flexible employment conditions based on the CAO-NU.

In addition to the collective employment conditions, Utrecht University has a number of schemes and facilities of its own for employees. These include agreements on professional development, leave arrangements, sports and cultural schemes, and you get discounts on software and other IT products. We also give you the opportunity to expand your terms of employment through the Employment Conditions Selection Model. This is how we encourage you to grow. For more information, please visit Working at Utrecht University.

For informal questions (not for application), contact Dr Ylona van Dinther at y.vandinther@uu.nl.

To apply, please follow the link tot the corresponding advertisement on our own website and follow the guidelines mentioned there. The application deadline is April 16h, 2025. The preferred starting date is Summer 2025 or as soon as possible thereafter.

Note that international candidates that need a visa/work permit for the Netherlands require at least four months processing time after selection and acceptance. This will be arranged with help of the International Service Desk of our university. Finding appropriate housing in or near Utrecht is your own responsibility and, unfortunately, we must warn that it is a tight market at the moment. In case of general questions about working and living in The Netherlands, please consult the Dutch Mobility Portal.

Online screening may be part of the selection. Commercial response to this ad is not appreciated.