Person:
Tsige Beyene, Meaza

First Name

Meaza

Last Name

Tsige Beyene

URI

https://hdl.handle.net/20.500.14352/75198

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Geológicas

Department

Geodinámica, Estratigrafía y Paleontología

Area

Geodinámica Interna

Identifiers

Full item page

Search Results

Now showing 1 - 10 of 44

Análisis de alterabilidad y estabilidad de taludes en las arcillas-margosas y arenas del Mioceno de Villalonquejar (Burgos)
(Geotemas, 2004) Rodríguez Escribano, R.; Tsige Beyene, Meaza
This study attempts a comprehensive review of the casual factors, which are controlling the frequent slope failures in the Miocene sediments at the Villalonquejar area (Burgos). For the purpose, an extensive study of both field and laboratory study of weathered and unweathered material was undertaken. The study involved insitu observation of both natural and artificially cut slopes, (mechanism, typologies and failure condition) as well as a survey of some of their engineering properties. The effect o f this process has been estimated using, laboratory test and slope stability analysis considering a circular failure. The results have shown that the main process of slope instability in these sediments is degradation and erosion due to wetting-drying cycles.
Factores litológico-geotécnicos en el peligro de movimientos cosismicos de ladera en El Salvador
(Proceddings de XII Congreso Geológico Chileno, 2009) Tsige Beyene, Meaza; García Flórez, Ignacio; Martínez Díaz, José Jesús; Capote Del Villar, Ramón
Se estudia los factores geológicos y estructurales que han controlado la distribución de los movimientos de ladera disparados por los terremotos del enero y febrero 2001 en El Salvador.
Newmark displacement data for low to moderate magnitude events in the Betic Cordillera
(Data in Brief, 2020) Delgado, José; Rosa, Julio; Peláez, José A.; Rodríguez Peces, Martín Jesús; Tsige Beyene, Meaza
Land-use decisions in relation to seismic-induced landslide hazard are usually made through the preparation of hazard maps. The rigid-block method is probably the most used for this purpose. Under this method, Newmark displacement is computed for each slope unit and this displacement is used as a guide for establishing categories of hazard. At present, most relations used for computing Newmark displacement are established from moderate-to-high magnitude earthquakes (Mw ≥ 6.5). This data article provides Newmark displacements computed from accelerograms recorded in the Betic Cordillera for low-to-moderate magnitude earthquakes (Mw = 3.5–6.3). Records come from the Spanish Strong Ground Motion database (Instituto Geográfico Nacional). Newmark displacements were computed focusing on yield accelerations frequently recorded in such scenarios (0.02, 0.03, 0.04, 0.05, 0.06, 0.08 and 0.10), although higher accelerations were also considered (0.125, 0.15, 0.20, 0.25 and 0.30 g's). These data are useful for the study of the hazard in seismic scenarios of low-to-moderate magnitude, very frequent in practice. These data have been used in the study by Delgado et al.
Propiedades geotécnicas de los sedimentos de la laguna Altillo Chica(Toledo): implicación en la formación de estructuras de erosión
(Geogaceta, 2019) Pulmariño Martín, Álvaro; Tsige Beyene, Meaza; Sanz Montero, María Esther
En el lecho de la laguna de Altillo Chica, situada en el municipio manchego de Lillo, se observan trazas, a modo de surco, dejadas por materiales pétreos, de distintos tamaños, al desplazarse. El origen de estas estructuras de erosión (groove marks) en superficies tan llanas todavía es controvertido. En este trabajo se estudian las propiedades físicas, estructurales y resistentes del sedimento lagunar que pudieran justificar la formación de dichas estructuras. El sedimento,que se ha caracterizado como limo yesífero, presenta unos parámetros resistentes muy elevados que no justifican por sí solos los movimientos de losbloques en pendientes tan bajas. Los elevados valores de resistencia pueden deberse a la humedad higroscópica y capacidad de succión de estos depósitos
Canal STEREOVIDEO: Vídeos cortos online para el aprendizaje de la técnica de representación estereográfica en Geología Estructural e Ingeniería Geológica
(Geotemas, 2016) Insua Arévalo, Juan Miguel; Castiñeiras García, Pedro; Álvarez Gómez, José Antonio; Rodríguez Peces, Martín Jesús; Martínez Díaz, José Jesús; Tejero López, Rosa; Tsige Beyene, Meaza
En este trabajo se presenta el canal de vídeos online STEREOVIDEO ubicado en el sitio web YouTube (https://www.youtube.com/user/geostereovideo). Se trata de un canal de vídeos didácticos de corta duración (< 5 min) destinados al aprendizaje del manejo de la técnica de la proyección estereográfica aplicada a la Geología Estructural y a la Ingeniería Geológica. Este tipo de vídeos pretenden reforzar el tradicional método didáctico presencial con la utilización de recursos virtuales. De esta manera se facilita la posibilidad de profundizar en aspectos más conceptuales de cada disciplina una vez dominado el manejo de la herramienta de representación. La presente comunicación muestra las características de los vídeos: desde su propio contenido didáctico, a aspectos más técnicos relacionados con la estructura, grabación y edición de los mismos, en los que se detalla tanto el material audiovisual, como el software utilizado.
Regional-scale high-plasticity clay-bearing formation as controlling factor on landslides in Southeast Spain
(Geomorphology, 2010) Azañón, J.M.; Azor Pérez, Antonio; Yesares, Jesús; Tsige Beyene, Meaza; Mateos Ruíz, Rosa María; Nieto, Fernando; Delgado, Jorge; López Chicano, Manuel; Martín, Wenceslao; Rodríguez Fernández, José
Complex landslides in clay-bearing sediments are investigated in two moderate-relief regions of Southeast Spain. Both regions, more than 100 km apart show landslides affecting the same Flysch formation, which outcrops widely in the central and western Betic Cordillera along the contact between the External (South Iberian Domain) and Internal (Alborán Domain) zones. Intense rainfall episodes can be considered as the main triggering factor for slope failures in these two areas. We have chosen two landslides (Diezma and Riogordo landslides), one from each area of study, to investigate their morphological and geotechnical features in order to establish the relative importance of the different controlling factors. From a kinematic point of view, the two features studied in detail can be referred as to rotational failures, evolving downhill to slow earthflows. The movement was concentrated on several surfaces developed on a clay-rich layer mostly constituted by smectite. This clay mineral is of critical relevance to the mechanical behaviour of soils and Flysch-like formations, being very consistent at dry conditions, but rapidly losing its strength at wet conditions. Thus, softened smectite-rich clay layers with high water contents can approach the properties of a lubricant, which, in turn, can be critical for slope stability. In addition to their high plasticity, these clays have a high swelling potential, which can induce significant vertical overpressure, thus reducing even more the strength properties of the Flysch formation. In Southeast Spain, a region with a Mediterranean rainfall regime, slope stability can be seriously influenced by the presence of these smectite-rich clay layers in a formation of regional extent, as is the case of the Flysch formation. Therefore, this lithologically-controlled factor should be taken into account when evaluating landslide hazard in the Betic Cordillera.
Caracterización geológica y sismotectónica del terremoto de Mula (febrero de 1999, Mb: 4,8) mediante la utilización de datos geológicos, sismológicos y de interferometría de RADAR (INSAR)
(Boletín geológico y minero, 2002) Martínez Díaz, José Jesús; Rigo, A.; Louis, L.; Capote Del Villar, Ramón; Hernández Enrile, José Luis; Carreño, E.; Tsige Beyene, Meaza
La secuencia sísmica de Mula (Murcia) iniciada el 2 de Febrero de 1999 con un terremoto máximo de Mb: 4,8 alcanzó una intensidad MSK máxima de VI-VII causando numerosos daños materiales. Los datos sismológicos existentes hasta la fecha, y concretamente la profundidad hipocentral y los mecanismos focales difieren de forma significativa en función del método de cálculo usado. En este trabajo se ha utilizado una técnica novedosa como es la interferometría de RADAR (INSAR) con el fin de identificar posibles deformaciones superficiales asociadas el terremoto que ayuden a identificar la fuente sismogenética. La combinación de los resultados obtenidos con esta técnica unidos a los datos geológicos de superficie apunta, como fuente más probable, a la reactivación de la falla de Crevillente con una componente de desgarre importante y con un epicentro somero (profundidad inferior a 10 km).
Lacustrine chalky carbonates: origin, physical properties and diagenesis (Palaeogene of the Madrid Basin, Spain)
(Sedimentary Geology, 2006) Arribas Mocoroa, María Eugenia; Bustillo Revuelta, María Ángeles; Tsige Beyene, Meaza
The Palaeogene lacustrine chalky carbonates of the Madrid Basin are a peculiar type of very soft and friable carbonate facies with high porosity despite being covered by more than 800 m of sediment. Similar physical properties to those described in marine chalk reservoirs emphasize the interest in analysing and characterizing these carbonate facies within a lacustrine depositional system. Lithologically, they are calcitic and/or dolomitic poorly cemented carbonate muds with no significant amounts of skeletal debris. Clay minerals such as illite, smectite and palygorskite are present between the carbonate crystals. Palygorskite is the most common, covering the carbonate crystals and forming sheets between them. These lacustrine chalky carbonates were formed in the basinal areas of the lake as the result of inorganic carbonate precipitation and/or detrital sedimentation related to episodic reactivation of the adjacent fan systems. Their petrological, geochemical and physical properties indicate that few textural and compositional modifications occurred during diagenesis. Their main physical properties are a very low dry bulk and grain density (1.6–2.2 and 2.62 g/cm3, respectively) and medium to high porosity (10–40%) due to micropores ( < 2 Am, 70%) and macropores (>2 Am, 30%). The convergence of lacustrine sedimentation dynamics (rapid sedimentation), the original mineralogy of these calcareous lacustrine muds (relatively stable low-magnesian calcite and dolomite), the early formation of the palygorskite cement of these muds, and the retention of Mg-enriched fluids in the pore system, were decisive in the partial inhibition of calcite cementation, compaction and recrystallization. The chalky carbonates are also intercalated between impermeable littoral carbonate facies that impeded fluid flow through their pore systems.
Grandes deslizamientos históricos en la isla de Mallorca: Biniarroi, 1721
(Geotemas, 2008) Mateos, R.M.; Giménez, J.; Tsige Beyene, Meaza; Azañón, J.M.
El valle de Biniarroi, situado en el t.m. de Mancor del Vall en la isla de Mallorca, sufrió en el mes de marzo del año 1721 uno de los mayores deslizamientos registrados en las Baleares. La elevada pluviometría de aquel invierno fue el desencadenante de la ocurrencia de un deslizamiento complejo, que afectó a unos 300.000 m2 de tierras de labor, modificando totalmente la topografía original de la zona así como la red superficial de drenaje del valle. Este deslizamiento y reactivaciones posteriores en los años 1816, 1857 y 1943 determinaron el abandono de este núcleo de población y de las aledañas tierras de cultivo. La recuperación de documentos históricos sobre el deslizamiento, junto al estudio y análisis del terreno, ha permitido reconstruir el deslizamiento original, sus dimensiones y características, así como la tipología del movimiento.
Pulverized quartz clasts in gouge of the Alhama de Murcia fault (Spain): Evidence for coseismic clast pulverization in a matrix deformed by frictional sliding
(Geology, 2020) Rodríguez Escudero, Emilio; Martínez Díaz, José Jesús; Giner Robles, Jorge Luis; Tsige Beyene, Meaza; Cuevas Rodríguez, Jaime
The fault gouge of the Alhama de Murcia fault (southeast Spain) shows a texture that resembles a mylonite, including a prominent foliation, S-C fabric, and isoclinal folds. It also embeds a large number of isolated pulverized quartz clasts (PQCs). Structural analysis indicates that the gouge fabric was mainly developed by slow frictional sliding along phyllosilicate-lined Riedel shear bands during continued shearing. In contrast, the PQCs show tensile fracture network features that are typically reported in seismically pulverized rocks found along seismogenic faults. This suggests that quartz-clast pulverization was due to a transient dilatational mechanism rather than shearing. We propose that the PQCs are the result of a rapid confined stress drop related to transient tensile stresses during coseismic ruptures that interrupt creep faulting along the gouge zone. The present study suggests that there is probably a large amount of evidence for paleoseismicity in fault rocks that is currently overlooked.