Skip to main content
Go to the home page of the European Commission (opens in new window)
English en
CORDIS - EU research results
CORDIS

BALancing Craton thickness by self-cOmpression, graiN size evolution and viscous anisotropY

Project description

Cratons: understanding the dynamical changes behind their average stability

Cratons, the stable interior part of Earth’s continents, are composed of ancient crystalline rock. Some cratons in Canada and Greenland have continental rocks dating back approximately 4 billion years. Although cratons have largely retained their 200-300-km thickness to the present with little internal deformation unlike other portions of the lithosphere (Earth’s two topmost layers), most cratons have experienced partial destruction. With the support of the Marie Skłodowska-Curie Actions programme, the Balcony project will investigate the hypothesis that a newly identified self-compressive mechanism causes them to slowly but continuously regrow with time. Time-dependent numerical models will help evaluate the thinning and thickening mechanisms.

Objective

Cratons, the oldest lithosphere on Earth, have survived for more than 3 billion years due to their neutral buoyancy, high viscosity, and thickness. The geologic record shows that, in the presence of external agents (e.g. mantle plume eruptions), most cratons have experienced partial destruction (e.g. Slave craton). Yet, cratons have retained their 200-300 km thickness more or less to the present-day. We hypothesize that a newly-identified self-compressive mechanism causes them to slowly but continuously regrow with time, promoting re-cratonization. Convective self-compression results from the diversion of mantle flow beneath thick and viscous cratonic roots, and is clearly observed and analysed in our recent numerical models. There may be temporary periods of imbalance if craton destruction is relatively new and self-compression has not had enough time to act (e.g. North China craton). Over time, self-compressive thickening may be balanced by increased shearing at the base of cratons due viscous anisotropy and grain size-dependent weakening. In this MSCA project BALCONY, I will use numerical models of cratons sitting above a convecting mantle to investigate how craton thickness may be maintained for billion years by the self-compression mechanism, despite destabilizing events and continuous erosion from below.
My objectives are to develop time-dependent numerical models to investigate (1) the effect of self-compression on craton re-thickening, (2) the importance of viscous anisotropy and grain size evolution for craton thinning, and finally (3) the balance between thickening and thinning, which ultimately determines the long-term thickness of cratons.
The project is a perfect overlap between the research interests of the supervisors (Clint Conrad, Agnes Kiraly at the Universtiy of Oslo) and myself. We are all interested in understanding lithosphere dynamics and have previous experience modelling craton stability, viscous anisotropy and grain size evolution.

Fields of science (EuroSciVoc)

Keywords

Programme(s)

Topic(s)

Funding Scheme

HORIZON-TMA-MSCA-PF-EF - HORIZON TMA MSCA Postdoctoral Fellowships - European Fellowships

See all projects funded under this funding scheme

Call for proposal

(opens in new window) HORIZON-MSCA-2022-PF-01

See all projects funded under this call

Coordinator

UNIVERSITETET I OSLO
Net EU contribution
€ 226 751,04
Address
PROBLEMVEIEN 5-7
0313 Oslo
Norway
Region
Norge Oslo og Viken Oslo
Activity type
Higher or Secondary Education Establishments
Links
Total cost
No data