Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/230724
COMPARTIR / EXPORTAR:
logo share SHARE logo core CORE BASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE

Invitar a revisión por pares abierta
Título

Geotechnical characteristics and slope stability on the Ebro margin, western Mediterranean

AutorBaraza, Jesús CSIC; Lee, Homa J.; Kayen, Robert E.; Hampton, Monty A.
Fecha de publicacióndic-1990
EditorElsevier
CitaciónMarine Geology 95(3-4): 379-393 (1990)
ResumenSedimentological and geotechnical analyses of core samples from the Ebro continental slope define two distinct areas on the basis of sediment type, physical properties and geotechnical behavior. The first area is the upper slope area (water depths of 200-500 m), which consists of upper Pleistocene prodeltaic silty clay with a low water content (34% dry weight average), low plasticity, and high overconsolidation near the seafloor. The second area, the middle and lower slope (water depths greater than 500 m), contains clay- and silt-size hemipelagic deposits with a high water content (90% average), high plasticity, and a low to moderate degree of overconsolidation near the sediment surface. Results from geotechnical tests show that the upper slope has a relatively high degree of stability under relatively rapid (undrained) static loading conditions, compared with the middle and lower slopes, which have a higher degree of stability under long-term (drained) static loading conditions. Under cyclic loading, which occurs during earthquakes, the upper slope has a higher degree of stability than the middle and lower slopes. For the surface of the seafloor, calculated critical earthquake accelerations that can trigger slope failures range from 0.73 g on the upper slope to 0.23 g on the lower slope. Sediment buried well below the seafloor may have a critical acceleration as low as 0.09 g on the upper slope and 0.17 g on the lower slope. Seismically induced instability of most of the Ebro slope seems unlikely given that an earthquake shaking of at least intensity VI would be needed, and such strong intensities have never been recorded in the last 70 years. Other cyclic loading events, such as storms or internal waves, do not appear to be direct causes of instability at present. Infrequent, particularly strong earthquakes could cause landslides on the Ebro margin slope. The Columbretes slide on the southwestern Ebro margin may have been caused by intense earthquake shaking associated with volcanic emplacement of the Columbretes Islands. Localized sediment slides on steep canyon and levee slopes could have been caused by less intense shaking. In general, the slope is stable under present environmental loading conditions and is fundamentally constructional. Nevertheless, rapid progradation caused by high sedimentation rates and other processes acting during low sea-level periods, such as more intense wave loading near the shelfbreak, may have caused major instability in the past. © 1990
DescripciónSpecial issue The Ebro Continental Margin, Northwestern Mediterranean Sea.-- 15 pages, 13 figures, 1 table
Versión del editorhttps://doi.org/10.1016/0025-3227(90)90125-4
URIhttp://hdl.handle.net/10261/230724
DOI10.1016/0025-3227(90)90125-4
Identificadoresissn: 0025-3227
Aparece en las colecciones: (ICM) Artículos

Mostrar el registro completo

CORE Recommender

SCOPUSTM   
Citations

39
checked on 19-abr-2024

WEB OF SCIENCETM
Citations

30
checked on 27-feb-2024

Page view(s)

67
checked on 21-abr-2024

Google ScholarTM

Check

Altmetric

Altmetric


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.