Structural Geology & Tectonics @ ETHZ

We are looking for B.S and M.S. students! See below for open research topics:

Masters Theses in the Rock Deformation Laboratory

Structural Geology and Tectonics Group @ ETH Zurich

Primary Supervisor: Dr. Leif Tokle (email)

Co-supervisor: Prof. Dr. Whitney Behr

The goal of the rock deformation lab is to understand and constrain micromechanical processes and their application to large-scale tectonic processes such as plate boundary shear zones and planetary dynamics. To do this we conduct high pressure and temperature deformation experiments, together with a variety of microstructural analyses. Masters projects can involve characterizing mechanical relationships (flow laws), understanding the effect of secondary phases on the rheology of a polyphase rock, or understanding the influence of extrinsic and intrinsic variables (Temperature, pressure, stress, strain rate, fluid content, grain size) affect a minerals mechanical properties.

Potential M.S. Projects*

• Developing a diffusion creep flow law for either muscovite or biotite
• Effect of muscovite on the brittle-ductile transition in a micaceous quartzite
• Effect of fluid chemistry on quartz-muscovite aggregates
• Quantifying the viscous anisotropy of a foliated blueschist
• Characterizing the effect of stress pulses (simulated earthquakes) on quartz microstructures

*For more detailed information on these projects, contact Leif Tokle.

General Tasks

-Conduct rock deformation experiments (trained by Leif Tokle)

-Microstructural analysis (petrographic and electron microscopy)

-Processing and integrating mechanical data

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Masters Theses on 4D, multi-scale analyses of faults and shear zones

Structural Geology and Tectonics Group @ ETH Zurich           

Primary Supervisor: Dr. Alberto Ceccato (email)

Co-supervisor: Prof. Dr. Whitney Behr

The geometry of faults and shear zones controls the strength and the permeability of the lithosphere, thus affecting seismicity and the distribution of mineral (ore) and water resources (hydrology) throughout the crust.

In this Master Thesis, you will explore how the geometry of faults and ductile shear zones evolve in space and through time. We will work together on the multi-scale characterization of brittle faults and ductile shear zones in crystalline units of the Alps. You will integrate the results of robust field geology with cutting-edge analytical investigations and 3D digital geological modelling at multiple scales, from the thin section to the outcrop, and to the orogen scale. 

The final goals of the Master Thesis are 

1) to understand the evolution in time and space of the geometry of deformation zones; 

2) to analyze the relationships between the evolving geometry and the geology, petrophysics, and rheology/mechanics of deformation zones; 

3) to provide geologically-sound, 4D (=3D+time) fault/shear zones models and discuss their implications on strain localization, earthquake mechanics, ore mineralization, etc.

General tasks

• Field structural analyses of selected faults and shear zones
• Elaboration of 3D geological and structural models from photogrammetry (LiDAR/iPad – Drone; Leapfrog)
• Microanalytical investigations (optical microscopy, electron microscopy/spectroscopy, geochronology);
• Matlab/R/FracPaQ/Perple_X modelling depending on the chosen topic.

Proposed topics for Master thesis

Tectonic inheritance controls on the geometry and mechanics of faults and ductile shear zones.

Origin and fate of mineralized ductile shear zone: relationship between deformation and mineral resources.

Multi-scale, field and statistical analyses of networks of faults and shear zones in crystalline basement of the Alps.

Automated fault zone detection from 3D point clouds with deep learning (in collaboration with Dr. Alexis Shakas).

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Masters Theses in structural geology, petrology and geochronology – from the field- to the thin section-scale

Primary Supervisor: Dr. Silvia Volante (email)

Co-supervisors: Dr. Leif Tokle and Prof. Dr. Whitney Behr

Structural Geology and Tectonics Group at ETH Zürich

To investigate complex collisional orogens earth scientists are challenged by the ability to interrogate the poorly preserved rock record through continuous development and application of novel, multi-scales, and interdisciplinary approaches. We combine structural and petrological field mapping together with a variety of in-situ microanalytical analyses.

Master projects can involve (the 1), 2), 3) components can be integrated as preferred by the student):

1. Field-based thesis: 3D drone imaging combined with 2D structural and petrological mapping of metamorphic and deformed terranes to generate a 3D map of the studied area. 

2. Microstructures: microstructural analysis of deformed and metamorphosed rocks integrated with imaging using scanning electron microscope (SEM) and mineral chemistry of major (e.g., garnet, mica) and accessory (e.g., monazite, zircon, rutile, titanite) minerals using the electron microprobe (EPMA) to study chemical and physical processes recorded at the thin section scale. 

3. Petrology-Geochronology-Geochemistry: for this type of thesis the student will have to integrate thin section observations with geochronological and geochemical data. For this purpose, the laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) laboratory will be used. 

Potential M.S.c Projects localities*

• Multi-scale petro-structural characterisation of eclogites and grt-schists from the Tauern Window (Eastern Alps)
• Multi-scale petro-structural characterisation of the Sorø Shear Zone Belt in SW Greenland

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Bachelor Theses in micro-structural and petro-analytical investigations 

Primary Supervisor: Dr. Silvia Volante (email)

Co-supervisor: Prof. Dr. Whitney Behr

Structural Geology and Tectonics Group at ETH Zürich

Bachelor projects can involve:

1. Field-based thesis: 3D drone imaging and 2D mapping of deformed rocks to generate a 3D visualization model of complex structures. 

• Microstructures: microstructural analysis of deformed and metamorphosed rocks integrated with mineral chemistry of major (e.g., garnet, mica) and accessory (e.g., monazite, zircon, rutile, titanite) minerals to study chemical and physical processes recorded at the thin section scale. 

The 1)-2) components can be integrated as preferred by the student.

Potential B.S.c Projects*

• Micro-scale investigations of deformed rocks from the Archean Lewisian Gneiss Complex, NW Scotland
• Microstructural analysis of gneisses from the Archean Nuuk region, SW Greenland: 
• Micro-scale investigations of Alpine eclogite from the Tauern Window, eastern Alps 

*For more detailed information on these projects, contact Silvia Volante (link)

General Tasks

• Literature review of the chosen topic 
• Microanalytical investigations and data processing (optical microscope, electron micro probe analyser- EPMA / secondary electron microscope – SEM to acquire compositional maps of accessory and major minerals)
• Integration of acquired data and interpretations

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 Proposal for Master Thesis

Supervisors: Dr. Jesús Muñoz-Montecinos (email) & Dr. Joaquin Bastias-Silva

 Motivation 

High-pressure low-temperature rocks are scarcely distributed in the continental crust. They are associated with the development of convergent margins, which are notably exposed in the circum-Pacific region. However, while most of this region is an active or recently active margin, high-pressure low-temperature rocks are locally exposed, which consequently generated a lesser understanding of its formation and timing conditions. Furthermore, our understand of the age and petrology of these rocks is particularly poor in more remote areas. The Antarctic Peninsula located ~2,000 km to the south of Patagonia host a few enigmatic exposures of high-pressure low-temperature assemblages. Smith Island, which is the southernmost island from the South Shetland Island archipelago, is dominated by blueschist and greenschist rocks. The island is 40 km long and 8 km wide and has a mountainous interior (the Imeon Range) that extends along the entire length of the island and has peaks over 2 km in height. Based on chemical analyses, suggested these rocks had a mid ocean ridge basalt protolith, while hemipelagic sediments from an ocean floor environment were also present. The age of these rocks is poorly constrained, 40Ar/39Ar ages in white mica yield ~58–47 Ma and ~65–63 Ma. To constrain the age of these rocks is critical to have a robust interpretation of its presence in this region of the margin, which remains unanswered. 

Main objectives 

This research is based on three fundamental objectives: 

• Determinate the age of the high-pressure low-temperature rocks exposed in Smith Island (Rb-Sr and U-Pb) 

• To characterize the mineralogy and geochemistry in order to determine its depositional-volcanic environment 

• Estimate the P-T conditions of the main peak paragenesis 

 Prerequisites 

• Skills to work with the petrographic microscope. 

• Taste for structural geology and petrology as well as motivation to learn new techniques. 

• Willing to learn about thermodynamic modelling (in collaboration with Pr. Andrea Galli) and geochronologic, cutting-edge techniques.