Numerical modeling on progressive internal deformation indown-built diapirs
2014 (English)In: Tectonophysics, ISSN 0040-1951, E-ISSN 1879-3266, Vol. 632, 111-122 p.Article in journal (Refereed) Published
A two-dimensional finite difference code (FDCON) is used to estimate the finite deformationwithin a down-builtdiapir. The geometry of the down-built diapir is fixed by using two rigid rectangular overburden unitswhich sinkinto a source layer of a constant viscosity. Thus, the model refers to diapirs consisting of a source layerfeeding a vertical stem, and not to other salt structures (e.g. salt sheets or pillows). With this setup westudy the progressive strain in three different deformation regimes within the “salt” material: (I) a squeezedchannel-flow deformation regime and (II) a corner-flow deformation regime within the source layer, and(III) a pure channel-flow deformation regime within the stem. We analyze the evolution of finite deformationin each regime individually, progressive strain for particles passing all three regimes, and total 2Dfinite deformationwithin the salt layer. Model results show that the material which enters the stem bears inherited strainaccumulated from the other two domains. Therefore, finite deformation in the stem differs from the expectedchannel-flow deformation, due to the deformation accumulated within the source layer. The stem displays ahigh deformation zone within its center and areas of decreasing progressive strain between its center and itsboundaries.High deformation zoneswithin the stemcould also be observedwithin natural diapirs (e.g. Klodowa,Polen). The location and structure of the high deformation zone (e.g. symmetric or asymmetric) could revealinformation about different rates of salt supplies from the source layer. Thus, deformation pattern could directlybe correlated to the evolution of the diapir.
Place, publisher, year, edition, pages
Elsevier, 2014. Vol. 632, 111-122 p.
Numerical modeling, Salt tectonics, Progressive and finite deformation, Differential loading
Geosciences, Multidisciplinary Geology
Research subject Earth Science with specialization in Mineral Chemistry, Petrology and Tectonics
IdentifiersURN: urn:nbn:se:uu:diva-237448DOI: 10.1016/j.tecto.2014.06.005ISI: 000343378500009OAI: oai:DiVA.org:uu-237448DiVA: diva2:767997