Estudios Geologicos-Madrid最新文献

{"title":"Etude hydrogéologique des séries triasiques dans la région de Jeffara-Dahar (Sud Tunisien): Apport des diagraphies et de la sismique réflexion","authors":"R. Lasmar, R. Guellala, L. Zouhri, B. S. Naouali, M. Garrach, M. H. Inoubli","doi":"10.3989/EGEOL.42114.373","DOIUrl":"https://doi.org/10.3989/EGEOL.42114.373","url":null,"abstract":"The present study concentrates on the interpretation of well logs and seismic reflection data in the Jeffara- Dahar region (Southeast part of Tunisia) for a better characterization of the Triassic aquifer, a potential target of water supply. Lithological columns and their corresponding well logs reveal that Sidi Stout, Kirchaou and Touareg sandstones as well as Mekraneb and Rehach dolomites are the main reservoirs of the Triassic aquifer. Well log analysis highlights many permeable and fractured layers that could play an important role in the groundwater circulation. \u0000The interpreted seismic sections and the resulting isochrone maps show a tectonic influence on the Triassic aquifer geometry in the Jeffara-Dahar region. The normal faulting of E-W and NW-SE accidents created an aquifer compartmentalized by raised and tilted blocks. Seismic cross-sections reveal that this structure controls the depth of permeable formations and the circulation of groundwater. \u0000These results will be useful for rationalising the future hydrogeological research that will be undertaken in the Jeffara-Dahar area.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"12 1","pages":"044"},"PeriodicalIF":0.7,"publicationDate":"2016-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72882314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Los terremotos antiguos del conjunto arqueológico romano de Baelo Claudia (Cádiz, Sur de España): Quince años de investigación arqueosismológica","authors":"Pablo G. Silva, J. G. Robles, Klaus Reicherter, M. A. Rodríguez-Pascua, Christoph Grützner, I. Jiménez, P. García, Teresa Bardají, Gabriel Santos, E. Roquero, J. Röth, M. Á. Perucha, R. Pérez-López, B. F. Macarro, Antonio Miguel Martínez-Graña, J. Goy, C. Zazo","doi":"10.3989/EGEOL.42284.392","DOIUrl":"https://doi.org/10.3989/EGEOL.42284.392","url":null,"abstract":"This work illustrates the state of the art on archaeoseismology of the ancient Roman city of Baelo Claudia (Tarifa, Cadiz) after nearly fifteen years of research. This ancient Roman site was affected by two earthquakes in the years AD 40–60 and AD 260–290 which promoted important urban and architectural changes and eventually the destruction and further abandonment of the city in AD 365–390. Earthquake Archaeoseismological Effects (EAEs) are catalogued, described and mapped in the entire monumental sector of the city mainly witnessing the last earthquake which occurred in AD 260–290. Mapping of oriented EAEs illustrate damage distribution all over the lower sector of the city, as well as the occurrence of suspect coseismic landslide and tsunami events. The structural analysis of oriented EAEs throughout the entire mapped sector suggests that the intervening ground motion was preferentially oriented in a SW to NE direction. The geoarchaeological analysis and some relevant archaeological anomalies, strongly suggest the occurrence of coeval tsunami events during both ancient earthquakes, pointing to the occurrence of an offshore seismic source SSW of the city. Several N-S normal faults have been identified around the Bolonia Bay area and some of them continue offshore SSW of Baelo Claudia . These faults with clear Quaternary activity can be considered as the more probable seismic sources for the events affecting the ancient Roman site and they are consistent with the mapped damage orientation displayed by the structural analysis of EAEs within the old Roman city.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"5 1","pages":"050"},"PeriodicalIF":0.7,"publicationDate":"2016-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88215242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early pliocene fishes (Chondrichthyes, Osteichthyes) from Gran Canaria and Fuerteventura (Canary Islands, Spain)","authors":"Juan Francisco Betancort-Lozano, Alejandro Lomoschitz, J. Meco","doi":"10.3989/EGEOL.42380.399","DOIUrl":"https://doi.org/10.3989/EGEOL.42380.399","url":null,"abstract":"espanolLos dientes fosiles de peces estan contenidos en depositos marinos datados en ca 4.8 Ma de las Islas de Gran Canaria y Fuerteventura (Islas Canarias, Espana). Estas islas, situadas en el Giro subtropical del Atlantico Norte, pueden considerarse una estacion intermedia entre un Mar Caribe que estaba cercano al cierre del Paso de America Central, y el Mediterraneo en su primera etapa tras la apertura post-Mesiniense de Gibraltar. Ello permitia una comunicacion pantropical para los animales del necton que eran capaces de desplazarse a grandes distancias. Se identifican por primera vez los peces Chondrichthyes Carcharocles megalodon, Parotodus benedeni, Cosmopolitodus hastalis, Isurus oxyrinchus, Carcharias cf. acutissima, Carcharhinus cf. leucas, Carcharhinus cf. priscus, Galeocerdo cf. aduncus y las species de Osteichthyes Archosargus cinctus, Labrodon pavimentatum y Diodon scillae. Se ha observado coincidencia entre los ejemplares canarios y los encontrados en las Islas Azores, las costas pacificas de America y el mar Mediterraneo. EnglishFossil fish teeth are contained in marine deposits dated at ca 4.8 Ma found on the islands of Gran Canaria and Fuerteventura (Canary Islands, Spain). These islands, situated in the North Atlantic Subtropical Gyre, can be considered a mid-way stopover point between the Caribbean Sea, with the Central American Seaway about to close in this epoch, and the Mediterranean, in the first stage of its post-Messinian Gibraltar Seaway period. Accordingly, there existed extensive pantropical communication, particularly for nektonic animals capable of travelling large distances. In this paper, we present a number of fossil fishes, most of which are identified for the first time on the basis of their teeth: the Chondrichthyes species Carcharocles megalodon, Parotodus benedeni, Cosmopolitodus hastalis, Isurus oxyrinchus, Carcharias cf. acutissima, Carcharhinus cf. leucas, Carcharhinus cf. priscus, Galeocerdo cf. aduncus, and the Osteichthyes species Archosargus cinctus, Labrodon pavimentatum, and Diodon scillae. Coincidences are observed between these ichthyofauna and specimens found in the Azores Islands, the Pacific coast of America and the Mediterranean Sea.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"44 1","pages":"4"},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80553178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Agregación de sedimentos en una cuenca de llanura: utilización del Microscopio Electrónico de Barrido como herramienta de evaluación","authors":"P. A. Suárez, O. Orfeo","doi":"10.3989/EGEOL.42054.366","DOIUrl":"https://doi.org/10.3989/EGEOL.42054.366","url":null,"abstract":"The purpose of this study was to determine the presence of sedimentary aggregates, which affect the transport of fine sediments. This contribution explores the influence of organic matter and dissolved salts, as the main factors that determine the aggregation of particles. Bottom sediments of Negro river (tributary of the Parana River), flows in the Chaco province (North-East of Argentina), and were assessed by granulometric analysis in consecutive phases of sample processing, to evaluate the presence of aggregates. The relative abundance of the different sizes in each analyzed phase, was controlled by Scanning Electron Microscope (SEM). The obtained results represent the first quantitative set of values of sediment aggregation in a river of the Chaco Plain, and can be used as a reference for the characterization of other rivers of subtropical plains. The results of this study show that the aggregates formation was favored by the high concentration of dissolved salts, but also by the presence of organic matter, abundant in subtropical environments. It was concluded that it is not convenient to apply classical techniques of sediment particle disaggregation (chemical oxidation to remove organic matter and chemical dispersants to break down associated particles), in order to avoid misinterpretation of transport dynamics of sediments in the natural environment.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"128 ","pages":"038"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72427887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Las asociaciones de ostrácodos en secuencias aluviales como indicadores de cambios ambientales holocenos (Bardenas Reales de Navarra, Cuenca del Ebro, NE Península Ibérica)","authors":"Blanca Martínez-García, Oier Suarez-Hernando, Julio Rodríguez-Lázaro, Ana Pascual, A. Ordiales, Xabier Murelaga, C. Sancho, A. Muñoz, C. Osácar","doi":"10.3989/EGEOL.42054.367","DOIUrl":"https://doi.org/10.3989/EGEOL.42054.367","url":null,"abstract":"In this paper, the ostracod assemblages identified in three alluvial units preserved in Bardenas Reales de Navarra (Ebro Basin, NE Iberian Peninsula) have been studied, with the aim of reconstructing the palaeoenvironmental evolution of this area during the late Holocene. The most common ostracod species in the studied samples are Ilyocypris bradyi Sars and Paralimnocythere aff. psammophila (Flossner), accompanied by Pseudocandona albicans (Brady). Variations in their relative abundance along these alluvial units allow us to characterize internal changes in the depositional environment. Thus, the unit deposited between 4763±87 and 2848±55 years cal. BP is dominated by I. bradyi , indicating the presence of small streams with running water developed probably in fluvial flood plains. Nevertheless, from 2848±55 to 836±65 years cal. BP Paralimnocythere aff. psammophila is the dominant species, representing the establishment of an ephemeral and stagnant aquatic environment, mainly related with more arid climatic conditions (Medieval Warm Period). Finally, the ostracod assemblage identified in Recent times (191±97 to 127±82 years cal. BP) is mainly dominated by I. bradyi , which indicates the presence of running waters. This later assemblage probably defines the influence of cold and wet climatic phase (Little Ice Age) during Recent times in this area. The palaeoenvironmental evolution identified from the late Holocene according to ostracod assemblages in Bardenas Reales de Navarra shows good correlation with rapid climatic changes deduced from other continental records of the NE Iberian Peninsula.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"49 1","pages":"042"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79782641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estudio espectroscópico y DRX de afloramientos terrestres volcánicos en la isla de Tenerife como posibles análogos de la geología marciana","authors":"E. Lalla, Guillermo Lopez-Reyes, A. Sansano, A. Sanz-Arranz, D. Schmanke, G. Klingelhöfer, J. Medina-García, J. Martínez-Frías, F. Rull-Perez","doi":"10.3989/EGEOL.41927.354","DOIUrl":"https://doi.org/10.3989/EGEOL.41927.354","url":null,"abstract":"Several volcanic outcrops from Tenerife Island (Las Canadas Caldera, historical volcanism and Gu.imar-Malpais outcrop) has been selected as a potential terrestrial analog for Mars, regarding the Martian mineralogy and its volcanic characteristic. Diverse alteration processes, including weathering and hydrothermal alteration have been detected in these volcanics environments, which could be considered as part of a model for the primitive volcanic activity of Mars. \u0000The selected materials have been measured by micro-Raman spectroscopy, XRD and Mossbauer spectroscopy. The results show the primary mineralogy comprises on olivine, pyroxene and feldspar. Also, a wide variety of alterational materials, including oxides, clay minerals and carbonates have been detected. \u0000The results have proven to be a starting point to develop research focused to the development of science instrumentation for planetary exploration in volcanic environments. The instrumentation used was primarily through twin prototypes applied in space exploration such as XRD (on board at the NASA-MSL-Curiosity mission), Mossbauer spectroscopy (on board at the NASA-MER mission) and the future Raman instrument on ESA mission -ExoMars. In addition, the detected mineralogy is consistent with results reported on Mars. The Raman spectral analisys methods, characterization and identification, have been applied, where the analysis of the Raman profiles are extremely useful to clarify the geochemical origin of the mineral species. On the other hand, the results obtained by Raman have been confirmed by Mossbauer spectroscopy and X-ray diffraction.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"28 1","pages":"035"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88261724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hallazgo de restos de la serpiente Dinilysia patagonica Smith-Woodward 1901 en una nueva localidad del Santoniano de Patagonia, Argentina","authors":"Laura Natalia Triviño, A. Albino","doi":"10.3989/EGEOL.41858.347","DOIUrl":"https://doi.org/10.3989/EGEOL.41858.347","url":null,"abstract":"In this study, we describe new remains of the cretaceous snake Dinilysia patagonica from beds of the locality Barreales Norte, Bajo de la Carpa Formation (Upper Santonian), Neuquen province, Argentina. The material comprises the back of a partially preserved skull, articulated with a fragment of the compound bone, atlas and axis. Additionally, six fragments of precloacal vertebrae have been preserved. The assignation to Dinilysia patagonica is based on: large skull, otooccipital with long paraoccipital process adjacent to an elongate supratemporal that extends farther the level of the occipital condyle; well developed sagital crest of parietal bone, continuously joined with the supraoccipital crest; italics I -like prootic; wide, short and robust vertebrae; prezygapophyses long and highly inclined above the horizontal; triangular section of vertebral centrum; reduced prezygapophyseal process; flattened neural arches with straight posterior edge. This material adds a new Upper Cretaceous location for the distribution of the species at the north of the Neuquen River.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"11 1","pages":"033"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88663097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"La fracturation et les bandes de déformation dans la région d’El Kohol (Atlas saharien central, Algérie): analyse fractale, lois d’échelles et modèle de réseaux de fractures discrètes","authors":"Réda Samy Zazoun, A. Marok, L. Samar, M. Benadla, H. Mezlah","doi":"10.3989/EGEOL.42011.359","DOIUrl":"https://doi.org/10.3989/EGEOL.42011.359","url":null,"abstract":"The aim of this paper is focused on the study of natural fractures and deformation bands in El Kohol structure, located in the Djebel Amour in the Central Saharan Atlas, Algeria. The field observations and measurements were performed through two localities on the forelimb and two others on the backlimb of the structure. The outcrop study has shown the existence of five fracture sets and three deformation bands sets. The spacing and length distribution models of the different fractures sets obey to a power law. The mechanical layer thickness analysis for the whole formations shows the existence of twelve mechanical units with a stratabound control. The deformation bands show an increasing in their numbers, and a decreasing in their spacing when they approach the major faults. The fractal analysis of faults and fractures, as well as the deformation bands show a fractal character of 2D dimension. A good correlation coefficients is obtained from the comparison between the density and the intensity parameters (Pxy) calculated from the discrete fracture network (DFN) modelling, and those from the outcrops. The model developed is discussed related to deformation events recognized in the area.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"36 1","pages":"039"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90471736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Presence of Arctotherium (Carnivora, Ursidae, Tremarctinae) in a pre-cultural level of Bano Nuevo-1 cave (Central Patagonia, Chile)","authors":"P. Mendoza, F. Larraín, E. Bostelmann","doi":"10.3989/EGEOL.42011.357","DOIUrl":"https://doi.org/10.3989/EGEOL.42011.357","url":null,"abstract":"The description of an I3 assigned to Arctotherium sp. obtained from the Bano Nuevo-1 site (Central Patagonia, Chile) is presented. The finding was recovered from Layer 5 and it is associated to Macrauchenia sp., Lama guanicoe , Felidae, Camelidae, Equidae and Mylodontidae, within a sterile deposit of cultural material, dated between ca. 13.500 and 11.200 BP. Despite the fact that it is only a single specimen, such finding extends the known distribution for the genus in Chile.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"37 1","pages":"041"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80864458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Los gonfotéridos (Mammalia, Proboscidea) de Uruguay: taxonomía, estratigrafía y cronología","authors":"D. Perea, M. T. Alberdi","doi":"10.3989/EGEOL.41864.346","DOIUrl":"https://doi.org/10.3989/EGEOL.41864.346","url":null,"abstract":"A large sample composed of relatively fragmentary remains of Gomphotheriidae was found in Uruguay. Belonging to this family there are materials assigned to Camacho Formation (Late Miocene), and to Pleistocene to Early Holocene units (Sopas, Libertad and Dolores formations). The Camacho and Sopas formations contain remains of indeterminate Gomphotheriidae, and the species Stegomastodon platensis is identified for the Libertad and Dolores formations. We think taxonomically suitable to support the opinion that all gomphotherids inhabitants of South American plains pertain to the genus Stegomastodon and to consider that species as the only representative of the genus in South America.","PeriodicalId":50496,"journal":{"name":"Estudios Geologicos-Madrid","volume":"27 1","pages":"036"},"PeriodicalIF":0.7,"publicationDate":"2015-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81333605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}