Thermal-elastic stresses and the criticality of the continental crust


Autoria(s): Schrank, C.E.; Fusseis, F.; Karrech, A.; Regenauer-Lieb, K.
Data(s)

2012

Resumo

Heating or cooling can lead to high stresses in rocks due to the different thermal-elastic properties of minerals. In the upper 4 km of the crust, such internal stresses might cause fracturing. Yet it is unclear if thermal elasticity contributes significantly to critical stresses and failure deeper in Earth's continental crust, where ductile creep causes stress relaxation. We combined a heating experiment conducted in a Synchrotron microtomograph (Advanced Photon Source, USA) with numerical simulations to calculate the grain-scale stress field in granite generated by slow burial. We find that deviatoric stresses >100 MPa can be stored during burial, with relaxation times from 100's to 1000's ka, even in the ductile crust. Hence, grain-scale thermal-elastic stresses may serve as nuclei for instabilities, thus rendering the continental crust close to criticality.

Identificador

http://eprints.qut.edu.au/59816/

Publicador

Wiley-Blackwell Publishing, Inc.

Relação

DOI:10.1029/2012GC004085

Schrank, C.E., Fusseis, F., Karrech, A., & Regenauer-Lieb, K. (2012) Thermal-elastic stresses and the criticality of the continental crust. Geochemistry, Geophysics, Geosystems, 13(9), pp. 1-21.

Fonte

School of Earth, Environmental & Biological Sciences; Science & Engineering Faculty

Palavras-Chave #Burial #Continental Crust #Criticality #Heating #Internal Stresses #Thermal Elasticity
Tipo

Journal Article