PhD position on 'Micromagnetic Tomography for
Rock-Magnetism' (4 yrs)

Job description:

The Department of Earth Sciences currently seeks a highly motivated, high-potential applicant for a PhD position to work within the research project 'Micromagnetic Tomography for rock-magnetism' as part of an ERC Starting Grant that was awarded to Dr Lennart de Groot at the paleomagnetic laboratory Fort Hoofddijk.

Magnetisations stored in volcanic rocks are a vital source of information on the past behaviour of the Earth's magnetic field. Small iron-oxide grains in these lavas acquire a magnetisation that is proportional to the Earth's magnetic field at the time of cooling, but not all these grains are able to properly retain their magnetisation over geologic time. Traditionally, paleomagnetic measurements are done on bulk samples; all iron-oxide grains in a sample are measured simultaneously. The ill-behaved grains lead to low success rates in experiments that reconstruct the past strength of the Earth's magnetic field, success rates as low as 10% are common. Recently, our research group developed a new technique, Micromagnetic Tomography, that makes it possible to determine the magnetisations of individual iron-oxide grains in volcanic samples. The aim of this PhD project is to use Micro-Magnetic Tomography to determine which iron-oxide grains are reliable paleomagnetic recorders, and which grains should be avoided. This makes it possible to interpret only the signals of grains that are stable paleomagnetic recorders and unlock paleomagnetic information in lavas that currently is inaccessible.

The candidate will characterise the rock-magnetic behaviour of common iron-oxides in lavas and assess the stability of their magnetisations using micromagnetic modelling. During the project the candidate will be trained to use the Quantum Diamond Microscope currently being installed at Fort Hoofddijk. Furthermore, the candidate will work with the Micromagnetic Tomography inversion programmes being written in Python, and micromagnetic software, e.g. MERRILL.

The research team is highly interdisciplinary and includes project leader Dr Lennart de Groot (supervisor), and Prof Dr Karl Fabian (advisor, NTNU Trondheim). The team furthermore consists of two postdocs and three PhD candidates. Besides the PhD position advertised here, one PhD candidate will work on the computational challenges of Micromagnetic Tomography, and another on developing its empirical methodology further. Technical support is provided by a technician in the paleomagnetic lab. The research will be performed at Utrecht University.

Up to 10% of the candidate's time will be dedicated to assisting in the BSc and MSc teaching programmes of the Department of Earth Sciences. A personalised training programme will be set up, mutually agreed on recruitment, which will reflect the candidate's training needs and career objectives.


The successful candidate should be ambitious and have an MSc (or equivalent) in Earth Sciences, Physics, Mathematics, or Chemistry. A strong background in mathematics is essential. Experience with one or more of the following topics would be an advantage: analytical (laboratory) skills, rock-magnetism, scanning magnetometry, inverse theory, solid-state physics, micro-scale modelling of natural systems, and/or programming. A broad interest in geosciences, and the willingness and capacity to interact in a multidisciplinary team, are essential. The candidate should be fluent in both spoken and written English, since the host group is international in composition.

Terms of employment:

You will be offered a full-time PhD position, initially for one year with extension to four years in total upon a successful assessment in the first year, and with the specific intent that it results in a doctorate within this period.

Employment conditions are based on the Collective Labour Agreement of the Dutch Universities. The gross monthly salary starts at € 2,325 in the first year and increases to € 2,972 in the fourth year. The salary is supplemented by a holiday allowance of 8% of annual salary and a year-end bonus of 8.3% of annual salary per year. We offer a pension scheme, (partly paid) parental leave, collective insurance schemes and flexible employment conditions (multiple choice model).

Facilities for sports and childcare are available on our main campus (where the Department of Earth Sciences is situated), which is located only 15 minutes away from the historical city centre of Utrecht.

About the organisation:

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 3,400 students (BSc and MSc) and 720 staff, the Faculty is a strong and challenging organisation. The Faculty of Geosciences is organised in four Departments: Earth Sciences, Human Geography & Spatial Planning, Physical Geography, and Sustainable Development.

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. The department hosts a highly international group of more than 100 PhD students and postdoctoral researchers and houses a wide variety of world-class laboratories.

Additional information:

Informal enquiries about the position may be sent to Dr Lennart de Groot (project leader), via

How to apply:

To apply, please follow this link and the guidelines mentioned there. Applications will be accepted until July 15, 2020. Evaluations and interviews are planned soon thereafter. The intended starting date is between September 1, 2020 and February 1, 2021.

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

Everyone deserves to feel at home at our university. We welcome employees with a wide variety of backgrounds and perspectives.

Click here to view all Utrecht University ads on the site

posted: 19 May 2020     Please mention EARTHWORKS when responding to this advertisement.