Using travertine deformations to characterize paleoseismic activity along an active oblique-slip fault: the Alhama de Murcia fault (Betic Cordillera, Spain)
A preliminary paleoseismic study of travertine deposits cut by an active oblique-slip fault is presented. The Alhama de Murcia fault a ffects late Pleistocene and Holocene trave rtine deposits along the Lorca-Totana segment. Travertines along oblique-slip (reverse - sinistral) active faults have not...
| Autores: | , |
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| Formato: | artículo |
| Fecha de publicación: | 2001 |
| País: | España |
| Recursos: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/88479 |
| Acesso em linha: | https://hdl.handle.net/20.500.14352/88479 |
| Access Level: | acceso abierto |
| Palavra-chave: | 551.2(460.33) Paleoseismicity Travertine U/Th dating Alhama de Murcia fault Falla de Alhama de Murcia Paleosismicidad Travertino Datación U/Th Geodinámica 2506 Geología |
| Resumo: | A preliminary paleoseismic study of travertine deposits cut by an active oblique-slip fault is presented. The Alhama de Murcia fault a ffects late Pleistocene and Holocene trave rtine deposits along the Lorca-Totana segment. Travertines along oblique-slip (reverse - sinistral) active faults have not been reported. On the Alhama de Murcia fault, CaCO3 rich springs are linked to an extensional step-over and to releasing fault junctions in a reverse-sinistral fault zone. The sampling methodology for U/Th dating employed to avoid contamination (by choosing material from a geochemical closed system) is described. A petrographic analysis is necessary to ensure the quality of the samples. Terrace - mound, fissure-ridge, eroded sheets and range-front trave rtine deposits occur in the Alhama de Murcia fault zone. At Carraclaca a 15 m amplitude monocline fold was formed by the reverse movement of this fault which has been active since the late Pleistocene. The first available absolute ages for deformed and undeformed trave rtines yield a ve rtical slip rate of 0.08 mm/yr. It is possible to estimate 4818 yr of recurrence time for the northern branch given the slip per event on alluvial deposits in the southern branch of the Alhama de Murcia fault. |
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