Publication Date:
2023-02-12
Description:
We studied two structural profiles across subvertical thin shear zone in marble from quarry in Estremoz (Portugal) to clarify a relationship between AMS and strain in natural rocks. The mesoscopic fabric can be described as changing from the subhorizontal coarse-grained foliation towards the ∼2cm-wide shear zone center with subvertical fine-grained foliation. In microstructure, the shear zone records dynamic recrystallization of calcite aggregate which resulted in development of porphyroclastic microstructure with increasing proportion of fine-grained recrystallized matrix towards the shear zone center. Two distinct crystallographic preferred orientations of calcite were recorded. One related with porphyroclasts, characterized by subvertical orientation of calcite 〈c〉 axes and another associated with recrystallized matrix showing subhorizontal calcite 〈c〉 axes orientation. The majority of the rock mass is diamagnetic, corresponding well with the thermomagnetic curves, with local paramagnetic accumulations in form of thin bands.
Keywords:
Anisotropy-magnetic susceptibility, factor F, foliation; Anisotropy-magnetic susceptibility, factor L, lineation; Anisotropy-magnetic susceptibility, factor P, anisotropy degree; Anisotropy-magnetic susceptibility, factor Pj; Anisotropy-magnetic susceptibility, factor T; Anisotropy-magnetic susceptibility, factor U; Coordinate, x, relative; Coordinate, y, relative; Declination of principle axis K1; Declination of principle axis K2; Declination of principle axis K3; Description of symmetrical anisotropy of magnetic susceptibility tensor; Disused_marble_quary; Estremoz, Portugal; Fitting error angle of the principal direction; F-statistics of the test for anisotropy; Geological sample; GEOS; Inclination of principle axis K1; Inclination of principle axis K2; Inclination of principle axis K3; Magnetic field strength; Magnetic susceptibility; Operation mode; Rock type; Sample code/label; Specimen orientation declination; Specimen orientation inclination
Type:
Dataset
Format:
text/tab-separated-values, 8547 data points
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