PhD Position in Earth Sciences

Utrecht University

Faculty: Faculty of Geosciences
Department: Department of Earth Sciences
Hours per week: 36–40
Application deadline: 22 March 2026

Project Overview

The Department of Earth Sciences seeks a highly motivated PhD candidate with an MSc background in Earth Sciences, Hydrogeology, Physics, Environmental Engineering, or related fields. You will work on the project:

"Upscaling pore-scale behaviour of clay-interfaces in shallow groundwater systems, enabling sustainable subsurface utilisation."

Context:
Aquitards (low-permeability clay and peat layers) are critical for protecting groundwater systems. They seal and compartmentalise aquifers, protect drinking-water reservoirs from contamination, separate different groundwater compositions, and confine heat in geothermal and energy-storage systems. In urban coastal areas, aquitards interact with foundations, tunnels, and other infrastructure. Understanding their behaviour under changing environmental conditions is essential for sustainable subsurface use.

Responsibilities

During this four-year study, you will:

• Develop an integrated approach combining microfluidic experiments with numerical modeling
• Design and conduct experiments to investigate clay behaviour under stressors such as temperature fluctuations, pressure gradients, salinity changes, and wet-dry cycles
• Monitor permeability, particle mobilisation (turbidity), volume changes, and visualise flow pathways in real time
• Integrate experimental observations with numerical models to develop constitutive equations describing clay behaviour, including micro-fracturing and internal erosion
• Conduct column-scale experiments and modeling to validate pore-scale findings and extrapolate to field-scale conditions

Key research questions include:

1. How do changing environmental conditions weaken clay-substrate interfaces?
2. How do pore-scale processes like swelling and shrinkage generate microfractures and facilitate clay particle movement?
3. Can robust upscaling approaches from pore to field scale be developed for reliable predictions?

Answers to these questions will support sustainable subsurface engineering, protect drinking-water resources, enhance subsurface energy storage, and ensure resilient infrastructure.

Professional Development

• Personalized training programme tailored to your career objectives
• Approximately 20% of time dedicated to professional development, including courses, workshops, and teaching experience
• Exposure to diverse career paths in academia, government, and industry

Candidate Profile

Required Qualifications:

• MSc degree in Earth Sciences, Hydrogeology, Physics, Environmental Engineering, or related discipline (must be completed before start)
• Experience with experimental techniques (flow-through experiments, column studies, material characterization) and/or numerical modeling
• Strong analytical skills integrating experiments with computational approaches
• Proficiency in at least one programming language (Python, MATLAB, or similar)
• Theoretical background in porous media processes (fluid flow, reactive transport, soil-fluid interactions, geomechanics)
• Excellent English communication skills
• Motivation for multidisciplinary research bridging fundamental science and societal applications
• Willingness to engage with stakeholders from government and industry

Desirable Qualifications:

• Experience with microfluidics or microscale visualization techniques
• Background in clay mineralogy, colloid science, or soil mechanics
• Familiarity with DEM, pore-network modeling, CFD, or finite element methods
• Experience with image analysis or particle tracking
• Exposure to interdisciplinary research linking lab experiments to field-scale applications

Employment Conditions

• 1.0 FTE position for 1 year, extendable to 4 years upon successful assessment
• Intention is to complete a PhD within 4 years
• Working week: 36–40 hours
• Gross monthly salary: €3,059 – €3,881 (full-time, CAO NU P scale)
• Benefits: 8% holiday pay, 8.3% year-end bonus, pension scheme, partially paid parental leave, flexible employment conditions

Additional Utrecht University schemes include professional development, various types of leave, sports, and cultural activities.

About Utrecht University

• Mission: Leading research and teaching with a focus on sustainability and societal impact
• Faculty of Geosciences: 3,400 students (BSc/MSc), 720 staff
• Departments: Earth Sciences, Human Geography & Spatial Planning, Physical Geography, Sustainable Development
• Facilities include: Electron Microscopy Centre, GeoLab (Porous Media Lab), Earth Simulation Lab, HPC facilities

Location: Utrecht Science Park, Utrecht, Netherlands – excellent transport links, historical city centre, modern amenities, and rich cultural life

Application Process

Contact for informal information:
Dr Thomas Sweijen, Project Leader
Email: T.Sweijen@uu.nl

How to Apply:

• Applications must be submitted online via the ‘Apply Now’ button. E-mail applications cannot be accepted.
• Include:
  • Letter of motivation (why you are the best candidate, and why Utrecht University)
  • Curriculum vitae (courses and relevant experience)
  • Academic credentials (mark sheets, degree statements as available)

Timeline:

• Application deadline: 22 March 2026
• Ideal start date: 1 June 2026 or as soon as possible thereafter
• Note: International candidates requiring a visa/work permit need at least 4 months for processing

Additional Notes:

• Knowledge security screening may be part of the selection procedure
• Utrecht University values diversity and inclusivity across all staff members