Structural Geology

We study deformation and metamorphic processes in the Earth at all scales, from nanostructures to plate boundaries, using tools ranging from electron microscopy to field geology. Our investigations concentrate on studies of the Earth’s crust, upper mantle and polar ice sheets, with emphasis on the microstructure and composition, transport properties, rheology and tectonic history.

Our research finds applications in geohazards, energy, environment, climate and cryosphere related topics. The broad goal of our research is to provide a fundamental understanding of Earth material behavior, which is needed to model and to interpret both natural and human-induced phenomena occurring within and at the surface of the Earth.

The Structural Geology group manages the electron microscopy and electron microprobe facilities of the Department of Earth Sciences and participates in the electron microscopy centre, housed in the Faculty of Science of Utrecht University.

Research

Deformation of Earth Materials

An understanding of the deformation mechanisms and rheology of Earth materials is important in comprehending the dynamics of our active and hazardous planet. Integrated research using field studies, advanced microcopy and experimental work is needed to investigate key problems in the deformation behaviour of Earth materials, including the micro- and nanoscale mechanisms that control slip in seismic fault zones, and the coupling of recrystallization to solid-state flow during large strain deformation. The key flow issue controls the behaviour of trans-crustal faults or shear zones of the convecting mantle and of polar ice sheets. The internal crystal plastic flow of ice sheets is also an important, poorly understood, parameter in the large-scale flow and melting of glaciers and polar ice sheets. Current research on ice flow is funded by the (Helmholtz Young Investigators project; Ernst-Jan Kuiper, dr. Ilka Weikusat).

Field-based research on exposed crustal and mantle rocks, in exhumed terranes and xenolith samples, provides insights into the structure, formation, evolution and tectonics of both continental and oceanic lithosphere. Current research topics include the strength contrast between crust and mantle, the origin of metamorphic soles beneath ophiolites (ERC-SINK project; Kalijn Peters) the nature of the lithosphere-asthenosphere transition and also the nature and rheology of plate boundary shear zones (Marie Curie funded project; dr. Vasileios Chatzaras).

Nanogeoscience

The physical and chemical properties of the Earth and other terrestrial planets depend on the atomic to nanoscale structure of their constituent rocks, minerals and fluids. Nanoscience is concerned with investigating material properties that change as physical dimensions approach the atomic scale and quantum effects become important. Earth materials with at least one nanoscale dimension are ubiquitous and include fault rocks, magnetic particles in sediments, biominerals and nanofossils, exsolutions in igneous and metamorphic crystals, intercrystalline fluid films and weathering layers at mineral surfaces, as well as nanoparticles in the atmosphere, oceans and polar ice sheets. Crucially, almost all elementary interactions between the lithosphere, atmosphere, biosphere and hydrosphere generally occur at the nanoscale across mineral surfaces.  

Nanogeosciences involves the integration of microscopy, spectroscopy, and theoretical modeling combined with experimental and fieldwork studies on the bulk behaviour associated with nanoscale mechanisms. Electron microscopy and related spectroscopy methods have been key techniques in this field for decades. However, technical advances in instrumentation mean that the field of electron microscopy is now evolving to allow many new advances in the nanoscale study of the structure and properties of Earth materials.  Applications include probing the nanoscale structures and processes controlling the dynamic frictional behaviour of seismogenic faults (dr. Oliver Plümper, Bart Verberne). Within the strategic Sustainability theme of Utrecht University, the Faculties of Science and Geosciences are linking their research in the Energy and Resources sector, addressing both upstream and downstream aspects of the resources supply chain. Our research involves characterizing the nanoscale paths and processes controlling flow of natural gas in rocks (dr. Maartje Houben, dr. Yang Liu).

Extreme Metamorphism

The transformation of rocks and minerals at extremely high pressure and temperature is a fundamental process in the dynamic Earth. Our research on extreme metamorphism concentrates on ultra-high-pressure rocks, produced deep in the Earth and on the role of extraterrestrial impacts in Earth history. Furthermore, ultra-high pressure (UHP) metamorphic rocks exposed at the Earth’s surface provide key data on crustal subduction and/or eduction processes, the nature of deep fluids in the Earth, and crust-mantle interactions during subduction and continental collisions. Work on impact metamorphism has involved the development of new microscopy techniques for the fast identification of shocked minerals, enabling an improved understanding of the role and rate of extraterrestrial impacts in Earth history. Such impacts are a very special type of hazard, which occur infrequently but with devastating effects.

Fluid-rock interaction

Our research on fluid-rock and mineral interaction spans a large range of scales, from the fundamental interfacial physics of hydration reactions to the mechanisms of fluid release during rock dehydration in subduction zones. An aspect of this interaction is reaction-induced fracture as a potential mechanism for fluid flow and reaction in tight rocks (VENI funded; dr. Oliver Plümper).

Teaching

The staff members and PhD students of the Structural Geology Group teach undergraduate (BSc) and graduate (MSc) courses.

Bachelor's courses

Master's Courses

In addition, we are involved in the supervision of Bachelor and Master projects and internships.

Publications

For a full overview of the group's publications please see the publications page.

People

Academic staff

Prof Dr Martyn Drury
Dr Maartje Hamers
Dr Maartje Houben
Dr Leo Kriegsman
Dr Gill Pennock
Dr Oliver Plümper
Dr Herman van Roermund
Dr David Wallis

Phd Students

Markus Ohl
Kalijn Peters

Former group members

Dr Ilka Weikusat
Dr. Ernst-Jan Kuiper
Dr Vasileios Chatzaras
Dr Yang Liu
Dr Serguei Matveev
Dr. Matthijs de Winter
Dr Annelies van Hoesel
Dr Wouter van der Wal
Dr Côme Lefebvre
Dr Auke Barnhoorn
Dr Laurie Palasse
Dr Siska Valcke                         
Dr Xavier Maeder
Dr Dirk Spengler                         
Dr Bart Meijninger                      
Dr Kike Beintema                      
Dr Armelle Kloppenburg
Dr Kim Hein                              
Dr Andor Lips
Dr Arjan Dijkstra
Dr Bernard Blasband
Dr Fraukje Brouwer
Dr Pat Trimby

Solid Rock Seminars

Solid Rock Seminars are organized by the Experimental Rock Deformation and Structural Geology groups. These seminars are intended to exchange information about our research projects in an informal setting and are open to everyone that is interested.

If you would like to be on the mailing list for the Solid Rock Seminars or give a talk, please contact Maartje Houben.