OROG3NY is a research project focusing on a few key questions of mountain building. On one hand on the 3D structures that define a mountain belt, their variations in depth as well as along the arc, and the role of the lower crust. On the other hand on the processes that shape an orogen, such as earthquakes and metamorphic evolution. The project targets questions in the Himalayas and the European Alps with geophysical tools, such as seismology, gravimetry and numerical modelling.

The project is funded by SNF (see summary in the P3 database), and hosted at the ISTE at UNIL.

We are interested in structures and processes governing the evolution of mountain belts, and to solve related questions using geophysical tools. Our work focuses mostly on the following projects:

  • Orogenic structures are rarely cylindrical: the closer one looks the more spatial variability one sees. Therefore there is an inevitable need to improve structural images towards 3D and higher resolution. A methodology to create 3D shear-wave velocity models from converted waves (receiver function) is a promising tool to characterize the crust and to identify the main lithologies. Leonardo Colavitti is developing a new approach in his Ph.D. thesis.
  • Metamorphic reactions affect rocks in the crust in various ways and strongly influence their geodynamic evolution. While these phase changes are well understood in the laboratory and at the rock sample scale, large scale observations from geophysics are scarce. As her post-doc research Kristel Chanard focuses on geophysical signals related to metamorphism to decipher more information about their large-scale characteristics and mechanism.
  • AlpArray is a European initiative to advance our understanding of orogeny and its relationship to other geodynamic processes and hazards in the Alps-Apennines-Carpathians-Dinarides system. The project integrates high-resolution geophysical imaging of 3D structures and physical properties of the lithosphere with focus on a high-end seismological array. György Hetényi is involved both in the research and in the general management of the project.
  • Bhutan, a kingdom in the Eastern Himalayas, is a blank spot on the geophysical map of the region. In the past 5 years György Hetényi was leading two geophysics projects to geophysically map Bhutan (using gravity anomalies, and a broadband seismology array in project GANSSER), and participated in a number of other projects with colleagues from Montpellier (see report and interview).
  • The Eastern Alpine Seismic Investigation (EASI) project is carried out as the first “AlpArray Complementary Experiment”, featuring a north-south array of 55 broadband stations along ca. 13.4°E across the Alps. With this György Hetényi and colleagues in Zürich, Prague and Vienna aim to characterize how Europe and Adria plate lithospheres meet at depth, especially the gap between their Mohos and the role of their lower crust.

Beyond these main themes, we work together with other researchers on various topics, mostly related to orogeny and geophysics.