Person:
Llanes Estrada, María Pilar

First Name

María Pilar

Last Name

Llanes Estrada

URI

https://hdl.handle.net/20.500.14352/75225

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Geológicas

Department

Geodinámica, Estratigrafía y Paleontología

Area

Geodinámica Interna

Identifiers

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Now showing 1 - 10 of 28

Bouguer anomalies of the NW Iberian continental margin and the adjacent abyssal plains
(Journal of Maps, 2019) Druet Vélez, María; Muñoz Martín, Alfonso; Granja Bruña, José Luis; Carbo Gorosabel, Andrés; Llanes Estrada, María Pilar; Catalán, Manuel; Maestro, Adolfo; Bohoyo, Fernando; Martín Dávila, José
The NW Iberian continental margin has a complex structure, resulting from the succession of several rifting episodes close to a ridge triple junction, and a superimposed partial tectonic inversion stage. The wide-ranging physiography matches the diverse tectonic deformation domains related to its evolution. Each deformation domain has a distinctive gravity signal, so the detailed Bouguer anomaly map presented here is a good first approach to the regional study of the whole margin. Moreover, as the presented chart is a complete Bouguer anomaly map (including terrain corrections), its analysis and interpretation can be done in terms of density, geometry and depth variations below the seafloor. This map is mainly based on the dataset obtained during seven one-month surveys carried out in the frame of the Spanish Economic Exclusive Zone project, and also includes two 2 + 3/4D density models illustrating the deep structure of the margin.
Morphostructure at the junction between the Beata ridge and the Greater Antilles island arc (offshore Hispaniola southern slope)
(Tectonophysics, 2014) Granja Bruña, José Luis; Carbo Gorosabel, Andrés; Llanes Estrada, María Pilar; Muñoz Martín, Alfonso
Oblique convergence between the Caribbean plate's interior and the inactive Greater Antilles island arc has resultedin the collision and impingement of the thickened crust of theBeata ridge into southern Hispaniola Island. Deformation resulting from this convergence changes from a low-angle southward-verging thrust south of easternHispaniola, to collision and uplift in south-central Hispaniola, and to left-lateral transpression along theSouthern peninsula of Haiti in western Hispaniola. Using new swath bathymetry and a dense seismic reflectiongrid, we mapped the morphological, structural and sedimentological Elements of offshore southern Hispaniola.We have identified four morphotectonic provinces: the Dominican sub-basin, the Muertos margin, the Beataridge and the Haiti sub-basin. The lower slope of the Muertos margin is occupied by the active Muertos thrustbelt, which includes several active out-of-sequence thrust faults that, were they to rupture along their entirelength, could generate large-magnitude earthquakes. The interaction of the thrust beltwith the Beata ridge yieldsa huge recess and the imbricate system disappears. The upper slope of the Muertos margin shows hick slopedepositswhere the extensional tectonics and slumping processes predominate. The northern Beata ridge consistsof an asymmetrically uplifted and faulted block of oceanic crust. Our results suggest that the shallower structureand morphology of the northern Beata ridge can be mainly explained by a mechanism of extensional unloadingfrom the Upper Cretaceous onward that is still active residually along the summit of the ridge. The tectonicmodels for the northern Beata ridge involving active reverse strike–slip faults and transpression caused by theoblique convergence between the Beata ridge and the island arc are not supported by the structural interpretation.The eastern Bahoruco slope an old normal fault that acts as a passive tear fault accommodating the sharpalong-strike transition from low-angle thrusting to collision and uplifting.
Geological evolution of the volcanic island La Gomera, Canary Islands, from analysis of its geomorphology
(Marine geology, 2009) Llanes Estrada, María Pilar; Herrera, R.; Gómez, M.; Muñoz Martín, Alfonso; Acosta, Juan; Uchupi, E.; Smith, D.
Erosion and landslide processes played an important role in shaping the geomorphology of the Canary Islands. But for the heavily eroded La Gomera Island, those processes have been unclear. We conducted an integrated study of its offshore extension, onshore geology, and links between them in order to determine the geomorphological evolution of the island relative to the rest of the archipelago. The characteristics of the island's barrancos and its interfluves have led us to differentiate four types of morphological areas whose fluvial networks are in different stages of evolution. Those barrancos offshore are interrupted by La Gomera's shelf, and its erosion has been much greater than for the rest of the Canary Islands. Such erosion is both a function of time and varied swell action. La Gomera's insular slope is carved by a system of submarine canyons and channels that have morphology indicative of turbidity current erosion. Many of the barrancos onshore and the canyons offshore have steps or knickpoints: some are the result of varied resistance to erosion, and others are explained by other mechanisms. A ridge whose crest is covered by cone-like shape structures is interpreted as of volcanic origin, with the particularity that it lacks onshore continuation, the opposite of what has been observed elsewhere in the Canary Islands. Also in contrast with the other islands of the archipelago, La Gomera's margin does not seem to have resulted from destructive mass wasting and the only offshore sign of catastrophic events are the presence of two embayments along La Gomera's northern shelf edge and a lobe structure on the insular apron at 3000 m depth. These features may be the remains of the catastrophic failures that took place on the island 9.4-8.7 Ma ago. Alternatively, they could be due to recent catastrophic failures on the upper slope due to sediment steeping. Since the conclusion of the main volcanic activity 4.0 Ma ago, La Gomera has been intensively eroded by gradual fluvial denudation and secondary failures. La Gomera's insular margin reveals much regarding its evolution, but more comprehensive studies including seismic and coring are needed to understand its whole geological history.
Morphological and structural analysis in the Anaga offshore massif, Canary Islands: fractures and debris avalanches relationships
(Marine Geophysical Researches, 2003) Llanes Estrada, María Pilar; Muñoz, Araceli; Muñoz Martín, Alfonso; Acosta, Juan; Herranz Araújo, Pedro; Carbo Gorosabel, Andrés; Palomo, Carlos
As part of the ‘National Hydrographic and Oceanographic Research Plan for the Spanish Exclusive Economic Zone’, multibeam bathymetry and seismic reflection profiles were obtained in the Canary Islands aboard the R/V Hespérides. The submarine flanks of the Anaga offshore extension of Tenerife Island are here studied to analyze its geomorphology. In the north sector of the Anaga submarine massif, the extension of the Anaga Debris Avalanche has been mapped for the first time, and a volume of 36 km3 was calculated. The relationship between the Anaga and Orotava Debris Avalanches is also described. Faulting has been recognized as a key process for the occurrence of debris avalanches and the growth of volcanic lineaments. Moreover, faulting affects previous structures and the channelling of debris flows. Structural analysis shows the typical radial pattern of an oceanic island. In addition, a NE-SW dominant direction of faulting was obtained, consistent with the Tenerife Island structural trend seen in the Anaga Massif and Cordillera Dorsal. NW-SE and E-W are two other main trends seen in the area. Special interest is manifest in two long faults: ‘Santa Cruz Fault’ bounds the southern edge of Anaga offshore Massif with a length of 50 km and a direction that changes from NE-SW to almost E-W. The Güimar Debris Avalanche was probably channeled by this fault. The ‘Guayotá Fault’ was recognized in several seismic profiles with a N-S direction that changes towards NW-SE at its southern end. This fault affects the more recent sediments with a vertical offset of 25–30 m, along 60 km. It has been interpreted as a transpressive strike-slip fault.
Nueva interpretación del relleno sedimentario de la Cuenca de San Pedro (Offshore de la República Dominicana) en base a nuevos datos sísmicos
(Geotemas, 2016) Gorosabel Araus, J.M.; Granja Bruña, José Luis; Carbo Gorosabel, Andrés; Gómez de la Peña, Laura; Rodríguez Zurrunero, Álvaro; Muñoz Martín, Alfonso; Pazos, Antonio; Gómez Ballesteros, María; Druet Vélez, María; Llanes Estrada, María Pilar
Los nuevos datos de sísmica de reflexión multicanal 2D adquiridos en la Cuenca de San Pedro (margen sudeste de la República Dominicana), junto con antiguos perfiles sísmicos reprocesados, han permitido llevar a cabo un detallado análisis y revisión de la estratigrafía sísmica. Los nuevos datos sísmicos aportan nuevas precisiones sobre la evolución de la cuenca sugiriendo un origen de al menos Eoceno Superior, en lugar de Mioceno. La nueva interpretación se basa en la correlación onshore-offshore de un nivel guía de abanicos bien desarrollado, con los eventos tectónicos constreñidos tierra y asociados a la colisión con los Bancos de las Bahamas con el arco isla el Eoceno Medio.
New Survey Explores the Northern Hispaniola Offshore Margin
(2015) Carbo Gorosabel, Andrés; Granja Bruña, José Luis; Rodríguez Zurrunero, Alvaro; Muñoz Martín, Alfonso; Gorosabel Araus, J.M.; Llanes Estrada, María Pilar; Druet Vélez, María
The highly oblique convergence between the North American and Caribbean plates has yielded that the thickened crust of Bahamas banks impinges into northern Hispaniola developing a narrow band of compressive deformation (northern Hispaniola margin) and a thick foreland basin (Hispaniola-Caicos basin). Approximately 280 km of 2D MCS profiles and 17000 km2 of high-resolution, systematic swath bathymetry data were recorded in the northern Hispaniola offshore margin in November-December of 2013 (NORCARIBE cruise). This is the first time that this region is explored systematically with highresolution multibeam bathymetry. Using new multibeam bathymetry and MCS data, combined we have studied the along- and across-strike variations of the shallower structure along a 330 km-long segment of the northern Hispaniola margin. Pronounced along-strike changes in structural style observed in the northern Hispaniola margin and Hispaniola-Caicos basin are associated with the active oblique underthrusting/indentation of the irregular boundary of the southernmost slope of the Mouchouir and Silver banks. The upper slope of the northern Hispaniola margin exhibits good economic potential associated to thick slope basins and terraces where is observable a continuous and prominent BSR. Preliminary results provide well- defined targets to carry out future exploration studies.
Shallower structure and geomorphology of the southern Puerto Rico offshore margin
(Marine and Petroleum Geology, 2015) Granja Bruña, José Luis; Ten Brink, Uri S.; Muñoz Martín, Alfonso; Carbo Gorosabel, Andrés; Llanes Estrada, María Pilar
Oblique convergence between the North American and Caribbean plates along the eastern Greater Antilles island arc has yielded the asymmetric Muertos thrust belt in the backarc region. Offshore south of Puerto Rico, this thrust belt disappears and is replaced by a succession of NEeSW- and EeW-trending deep basins and steep ridges that characterize the western Anegada passage, resulting in a complex deformation pattern. Using new high-resolution multibeam bathymetry and seismic reflection profiles, we studied the geomorphology and shallower structure of the southern Puerto Rico offshore margin. We have identified four morphotectonic provinces: the Puerto Rican sub-basin and Muertos trough, the Muertos margin, the insular shelf and the western Anegada passage. The Muertos margin province shows two distinct slope sub-provinces: the active Muertos thrust belt e which includes lower and upper thrust belts with distinct deformational styles and lateral continuity e and the shelf slope highly-incised by a dense canyon network. This network is disrupted by the Investigator fault zone consisting of a 130 km-long EeW-trending band of active extensional deformation. The Investigator fault zone shows differential surface expression caused by along-strike changes in the magnitude and distribution of the deformation, though this deformation is driven by a NeS-oriented extension. In the western Anegada passage province, the Whiting basin and Whiting and Grappler ridges are formed by large dip-slip normal faults driven by a NWeSE-oriented extensional regime. The western St. Croix rise shows a complex structure where the NEeSW-trending NW-dipping normal faults observed at the summit of the rise predate the EeW-bounding faults that could accommodate the extensional deformation at the Present. This study provides detailed observations on the active tectonic and sedimentary processes to help future studies assessing the natural resources and the seismic and tsunamigenic hazard in the Puerto Rico region.
Submarine landslide deposits of the historical lateral collapse of Ritter Island, Papua New Guinea
(Marine and Petroleum Geology, 2015) Day, Simon; Llanes Estrada, María Pilar; Silver, Eli; Hoffmann, Gary; Ward, Steve; Driscol, Neal
The March 13th 1888 collapse of Ritter Island in Papua New Guinea is the largest known sector collapse of an island volcano in historical times. One single event removed most of the island and its western submarine flank, and produced a landslide deposit that extends at least 70 km from the headwall of the collapse scar. We have mapped and described the deposits of the debris avalanche left by the collapse using full-coverage multibeam bathymetry, side-scan sonar backscatter intensity mapping, chirp seismic-reflection profiles, TowCam photographs of the seafloor and samples from a single dredge. Applying concepts originally developed on the 1980 Mount St. Helens collapse landslide deposits, we find that the Ritter landslide deposits show three distinct morphological facies: large block debris avalanche, matrix-rich debris avalanche and distal debris flow facies. Restoring the island's land and submarine topography we obtained a volume of 4.2 km3 for the initial collapse, about 75% of which is now forming the large block facies at distances less than 12 km from the collapse scar. The matrix-rich facies volume is unknown, but large scale erosion of the marine sediment substrate yielded a minimum total volume of 6.4 km3 in the distal debris flow and/or turbidite deposits, highlighting the efficiency of substrate erosion during the later history of the landslide movement. Although studying submarine landslide deposits we can never have the same confidence that subaerial observations provide, our analysis shows that well-exposed submarine landslide deposits can be interpreted in a similar way to subaerial volcano collapse deposits, and that they can in turn be used to interpret older, incompletely exposed submarine landslide deposits. Studying the deposits from a facies perspective provides the basis for reconstructing the kinematics of a collapse event landslide; understanding the mechanisms involved in its movement and deposition; and so providing key inputs to tsunami models.
Project number: 44
Geofísica-SMART: Simples experiMentos de enseñanza apRendizaje en entoRnos digiTales
(2022) Martín Hernández, Fátima; Ledo Fernandez, Juan José; Negredo Moreno, Ana María; Pavón Carrasco, Francisco Javier; Fullea Urchulutegui, Javier; Osete López, María Luisa; Ruíz Martínez, Vicente Carlos; Arquero Campuzano, Saioa; Llanes Estrada, María Pilar; Druet Vélez, María; Valles-Iriso, Javier; Gómez-Paccard, Miriam; Bonilla Alba, Raquel; Rivera Pérez, Pablo; López Sánchez, Carolina
La Geofísica es una disciplina asociada a la Física experimental con gran desarrollo en multitud de ámbitos que van desde la arqueología a diferentes areas de la ingeniería como la geotécnia, ingeniería de minas o ingeniería geológica o bien el ámbito académico. Precisa de un conocimiento Físico de las leyes de la naturaleza pero también una destreza asociada a la Física más aplicada con multitud de experimentos en campo. Éstos son a veces difíciles de encontrar en libros de texto que se centran en los aspectos teóricos de la disciplina. Por eso, este proyecto pretende hacer ver a los estudiantes el diseño, desarrollo y procesado de experiencias de Geofísica Aplicada o prospectiva dentro de su desarrollo curricular.
Estructura superficial y procesos activos en el margen submarino del norte de La Española (República Dominicana): Resultados preliminares
(Geotemas, 2016) Rodríguez Zurrunero, Álvaro; Granja Bruña, José Luis; Muñoz Martín, Alfonso; Carbo Gorosabel, Andrés; Gómez de la Peña, Laura; Gómez Ballesteros, María; Gorosabel Araus, J.M.; Pazos, Antonio; Catalán, M.; Druet Vélez, María; Llanes Estrada, María Pilar
El margen submarino del norte de La Española registra el proceso de colisión activa entre los Bancos de las Bahamas y el arco isla. Esta colisión ha producido numerosos terremotos causando cuantiosos daños en la costa norte de la isla. La campaña NORCARIBE (2013) combinó la adquisición sistemática de datos geofísicos de todo el margen subductivo, especialmente en la zona de República Dominicana, proporcionando una información continua y de alta resolución. Esta información ha permitido estudiar con detalle la variación transversal y longitudinal del margen subductivo caracterizado por la Fosa de la Española (FE) y el Cinturón Deformado Septentrional (CDS). Este margen compresivo presenta una estructura imbricada con vergencia hacia el norte y segmentada por zonas de transferencia limitando la longitud máxima de las fallas inversas. Existen numerosas evidencias de deformación activa que deben ser consideradas en futuros estudios sobre la evaluación de la peligrosidad sísmica y tsunamigénica en la región, así como para la evaluación de recursos marinos y la ordenación del territorio de la República Dominicana.