PhD in Earth Science - Characteristics of quaternary fault activities in the Armorican Massif using geomorphology and geophysical techniques

4 Apr 2024
Job Information

Organisation/Company

Nantes Université

Department

Laboratory of Planetology and Geosciences – UMR-CNRS 6112

Research Field

Environmental science » Earth science
Geosciences » Geology

Researcher Profile

First Stage Researcher (R1)

Country

France

Application Deadline

13 May 2024 - 23:59 (Europe/Paris)

Type of Contract

Temporary

Job Status

Full-time

Hours Per Week

35

Offer Starting Date

1 Oct 2024

Is the job funded through the EU Research Framework Programme?

Not funded by an EU programme

Is the Job related to staff position within a Research Infrastructure?

No

Offer Description

Context: France is situated far from plate tectonic boundaries and considered now a stable continental region with a very low strain rate, especially in the north west. However, the recent Mw4.9 2019 Le Teil and 2023 La Laigne earthquakes highlighted that active faults are not all clearly identified and should be better characterized. The Armorican Massif is cross-cut by several inherited faults and shear zones, which formed during the Cadomian and Hercynian orogens, the opening of Mezo-Cenozoic basins and several compressional phases over the Cenozoic. The historical and instrumental seismicity present a moderate activity, trending SE-NW, in agreement with the direction of main regional shear zones and faults. Besides these observations, identifying active faults (i.e., active over quaternary, then the last 2 Ma) and what drives the deformation, remains a difficult task. 

Objectives: this project proposes to analyze major faults of the Armorican Massif using high resolution data available since few years. Guided by the recent seismicity locations, and based on satellite images and topographic data, the PhD. candidate will first map precisely the fine structure of faults and analyze their interactions with the morphology and quaternary deposits. Then, sites of interests will be investigated during field work campaigns, where geological and geophysical tools will be deployed to characterize the fault structures at depth, and their links with the observed surface scarps. The goal will be to detect and localize possible discontinuities at depth in the quaternary deposits, identify their lithology and quantify their thickness. Finally, the PhD. candidate will perform paleo-seismological trenching to look for deformation in the quaternary deposits.

Environments and collaborations: the LPG (Nantes facility), through the OSUNA, is now in charge of the observation and characterization of seismic activities along faults and shear zones in the NW part of France, and involved in the development of new techniques to acquire high resolution topography (LiDAR). The PhD. candidate will benefit from the expertise of seismologists and geomorphologists in the lab, and regional collaborations in geomorphology and geophysics (Géosciences Rennes and Université Gustave Eiffel) in the frame of current projects (QASArm, ALEP, SALLE), funded by the observatory (OSUNA). Finally, the French action FACT (ACTive Faults) launched in 2019 through the research infrastructure Résif/Epos-France gather national experts in seismo-tectonics, collaborating each other to better understand active faults in France.

Requirements

Research Field

Environmental science » Earth science

Education Level

Master Degree or equivalent

Research Field

Geosciences » Geology

Education Level

Master Degree or equivalent

Skills/Qualifications

The PhD candidate will be a graduate student in Earth sciences and will need to use the common tools to study active faults (GIS, electric, seismic and radar geophysics). A good knowledge of basic notions in field work geology, geomorphology, tectonic and geophysics is required. A strong ability to work as a team is also required.

Languages

ENGLISH

Level

Good

Additional Information
Work Location(s)

Number of offers available

1

Company/Institute

Laboratory of Planetology and Geosciences – UMR-CNRS 6112

Country

France

City

NANTES

Postal Code

44000

Street

2 Rue de la Houssinière

Geofield

Where to apply

Website

https://theses.doctorat-bretagneloire.fr/3mg/campagne-2024/caracterisation-de-l…

Contact

City

NANTES

Website

https://lpg-umr6112.fr/
http://WWW.UNIV-NANTES.FR

Street

1 QUAI DE TOURVILLE, BP 13522, 44035 NANTES CEDEX 01

Postal Code

44000

E-Mail

[email protected]
[email protected]

STATUS: EXPIRED