×

Computer simulation of underthrusting and subduction due to collision of slabs. (Russian, English) Zbl 1212.86061

Sib. Zh. Vychisl. Mat. 12, No. 1, 71-90 (2009); translation in Numer. Analysis Appl. 2, No. 1, 58-73 (2009).
Summary: We come up with a mathematical simulation of a collision between lithospheric slabs (plates) where one slab is forced into the mantle beneath another. Problems of the Earth’s crust and mantle deformation are solved numerically: for spatial discretization of equations of deformable solid mechanics, a finite-element method is used, and for evolution of the collision process, a stepwise integration of quasistatic deformation equations is applied. Problems of plate motion are solved within a geometrically nonlinear setting in a two-dimensional approximation (plane deformation) with due regard for large deformations of bodies and contact interactions of slabs with the mantle. A numerical solution is obtained via a MSC.Marc 2005 code, encompassing formulations of equations with required types of nonlinearities. A part of the Earth’s crust that has no tendency to delving into the mantle is simulated by a prescribed motion of a rigid body. A part of the Earth’s crust that should sink by virtue of properties of initial geometry is simulated as a deformable solid made up of elastoplastic strain-hardening material. The mantle is simulated by an ideal elastoplastic material with a low yield stress value. We are concerned with parts of the Earth’s crust that have different geometric parameters. Computer simulation of plate collision shows that under standard conditions, underthrusting of one slab beneath another occurs; at sites of initial thickening of a slab in a contact zone, subduction (deep sinking) of the slab into the mantle is expected. In the latter case, account should be taken of a well-known experimental fact, that of material compaction of the sunken piece of a slab.

MSC:

86A17 Global dynamics, earthquake problems (MSC2010)

Software:

MARC
PDFBibTeX XMLCite