Correlation of sedimentary units from grain-size and mineralogic analyses as a tool for constraining trench interpretations in palaeoseismology

Ezquerro, Lope (Universidad de Zaragoza) ; Liesa, Carlos L. (Universidad de Zaragoza) ; Simón, José Luis (Universidad de Zaragoza) ; Arlegui, Luis Eduardo (Universidad de Zaragoza) ; Luzón, Aránzazu (Universidad de Zaragoza) ; Lafuente, Paloma (Universidad de Zaragoza)

Resumen: In palaeoseismological trench studies, precise correlation of sedimentary units between fault blocks has an unquestionable value for accurately inferring the amounts of coseismic displacement and hence for assessing seismic hazard. A methodology based on laser analysis of particle size and mineralogic composition by X-ray diffraction is proposed in order to strengthen the correlation of sedimentary units in a trench excavated across the Concud Fault (central Iberian Chain, Spain). The surveyed sediments show sharp and multiple lateral facies changes, as well as inconsistent optically stimulated luminescence (OSL) ages. The results reinforce the correlation based on field inspection of lithologic and sedimentologic features. Moreover, they allow interpretation of rejuvenation of OSL ages of samples in the upthrown fault block, which has been attributed to partial erosion of sedimentary units, as evidenced by their smaller thickness and erosive boundaries. The correlated units are then used to estimate coseismic displacements for three palaeoseismic events.

Idioma: Inglés

DOI: 10.1007/s00531-014-1079-5

Año: 2014

Publicado en: International Journal of Earth Sciences 103, 8 (2014), 2327–2333
ISSN: 1437-3254

Factor impacto JCR: 2.093 (2014)

Categ. JCR: GEOSCIENCES, MULTIDISCIPLINARY rank: 62 / 175 = 0.354 (2014) - Q2 - T2

Financiación: info:eu-repo/grantAgreement/ES/MINECO/BES-2010-031339
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CGL2009-13390
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CGL2012-35662

Tipo y forma: Revisión (Versión definitiva)

Área (Departamento): Área Geodinámica Interna (Dpto. Ciencias de la Tierra)
Área (Departamento): Área Estratigrafía (Dpto. Ciencias de la Tierra)