Shape preferred orientation of dolostone bodies of a Triassic broken formation at the western External Betics
- Manuel Díaz Azpiroz 1
- Rosa Asencio Almansa 1
- Juan Ramón Senín Andrades 1
- Alejandro Jiménez Bonilla 1
- 1 Dpto. Sistemas Físicos, Químicos y Naturales. Universidad Pablo de Olavid
ISSN: 0213-683X
Year of publication: 2020
Issue: 67
Pages: 11-14
Type: Article
More publications in: Geogaceta
Abstract
Detailed structural analyses of block-in-matrix formations are key to understand the tectonic processes involved in the external zones of many convergent orogens. One of these formations, with a highly controversial origin and evolution, marks the boundary be-tween the fold-and-thrust belt and the foreland basin of the Betics. We analyzed dolostone bodies from this block-in-matrix formation in the western External Betics (Badolatosa, Sevilla), affected by the Algodonales-Badolatosa shear zone, to obtain a partial SPO (θ an-gle between long axes and the shear zone boundary). Our results define a main 500-1200 m-wide band strongly controlled by de-formation at the WNW-NNW boundary of this shear zone. Minor, heterogeneously distributed bands with a moderate SPO are ten-tatively interpreted as Riedel shears related to dextral transpression.