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This article analyzes students’ perceptions of internal factors that influence their transition from elementary to secondary school. Two questionnaires were used to survey 168 students. The results indicate that most students have adequately adapted to the change. They also show that most students believe that it would be useful to meet their future teachers and tutors in advance. They also believe that they will make friends without difficulties; that their families will support them less in their secondary school activities; and that happiness is the feeling that best characterizes the transition. The conclusions emphasize that students have good expectations about their assumed greater autonomy in secondary school and that they consider it important to feel welcomed by their tutors and teachers. Students support the existence of good relationships between their families and teachers., Este artículo analiza la percepción del estudiantado sobre algunos factores internos que influyen en la transición de la primaria a la secundaria. Se aplicaron dos cuestionarios a 168 estudiantes. Los resultados indican que se han adaptado adecuadamente al cambio; la mayoría cree que sería conveniente conocer previamente al profesorado y tutorado de la siguiente etapa; que hará amistades sin problemas; que tendrá menor apoyo familiar para sus actividades escolares en la secundaria; y la alegría es el sentimiento que mejor caracteriza la transición. Entre las conclusiones destaca que el alumnado posee buenas expectativas en cuanto a la mayor autonomía que va a suponer la secundaria; considera importante sentirse acogido por sus tutoras(es) y profesoras(es); y apoya que exista una buena relación entre estos y sus familiares.

The subsurface sedimentary succession of the Iberian Trough, Spain was examined using geophysical t echniques (analogue seismic profiles) and inverse distance weighted (IDW) interpolation algorithm implemented in a gvGIS open source software. The results showed that the Late Cretaceous succession is divided into two depositional sequences: DS­1 (Late Albian–Middle Turonian) and DS­2 (Late Turonian–Campanian). From the analogical seismic sections, digital data and quantitative isopach maps for DS­1 and DS­2 were obtained. The new isopach maps obtained for the DS­1 sequence showed that the deeper sectors of the basin were located to the northeast and the proximal ones to the southwest. The palaeoshoreline was inferred to be situated in the N 150 direction. Across and parallel to this direction several blocks were delimited by faults, with a direction between 30 N and N 65. The thickness of the sediments in these blocks varied in direction NW–SE, with subsidence and depocentres in hangingwall and uplift in the footwall. These variations may have been related to active synsedimentary faults (e.g., Boñar and Yugueros Faults). In the DS­2 sequence, a lineament separated the smaller thicknesses to the southwest from the larger thicknesses (up to 1400 m) to the northeast. This lineament had an N170 orientation and it indicated the position of the palaeoshoreline. In the isopach map for DS­2 there were two groups of lineaments. The first showed a block structure that was limited by N100–120, they were foundering toward the S and had large thicknesses (depocentres), and rose towards the N, where there were smaller thicknesses. The second group of lineaments had a N 50–65 direction and, in this case, they had a similar interpretation as the one in DS­1. The maps obtained are of great help for geologists and permit better understanding of the geological setting and stratigraphic succession of the Late Cretaceous of the Iberian Trough.

The subsurface sedimentary succession of the Iberian Trough, Spain was examined using geophysical t echniques (analogue seismic profiles) and inverse distance weighted (IDW) interpolation algorithm implemented in a gvGIS open source software. The results showed that the Late Cretaceous succession is divided into two depositional sequences: DS­1 (Late Albian–Middle Turonian) and DS­2 (Late Turonian–Campanian). From the analogical seismic sections, digital data and quantitative isopach maps for DS­1 and DS­2 were obtained. The new isopach maps obtained for the DS­1 sequence showed that the deeper sectors of the basin were located to the northeast and the proximal ones to the southwest. The palaeoshoreline was inferred to be situated in the N 150 direction. Across and parallel to this direction several blocks were delimited by faults, with a direction between 30 N and N 65. The thickness of the sediments in these blocks varied in direction NW–SE, with subsidence and depocentres in hangingwall and uplift in the footwall. These variations may have been related to active synsedimentary faults (e.g., Boñar and Yugueros Faults). In the DS­2 sequence, a lineament separated the smaller thicknesses to the southwest from the larger thicknesses (up to 1400 m) to the northeast. This lineament had an N170 orientation and it indicated the position of the palaeoshoreline. In the isopach map for DS­2 there were two groups of lineaments. The first showed a block structure that was limited by N100–120, they were foundering toward the S and had large thicknesses (depocentres), and rose towards the N, where there were smaller thicknesses. The second group of lineaments had a N 50–65 direction and, in this case, they had a similar interpretation as the one in DS­1. The maps obtained are of great help for geologists and permit better understanding of the geological setting and stratigraphic succession of the Late Cretaceous of the Iberian Trough.

We study the volcaniclastic lithofacies interbedded between siliciclastic and carbonate sediments of Cenozoic-Quaternary age (8.7 Ma to 7,000 BP) in Argamasilla and Calzada-Moral basins (Central Spain). The siliciclastic and carbonate deposits correspond to fluvio-lacustrine sedimentary environments. The volcanic materials consist of primary and reworked volcaniclastic successions sourced from the Campo de Calatrava Volcanic Field. Pyroclastic deposits are related to monogenetic and small-volume volcanic centres, such as scoria cones, tuff rings and maars, corresponding to Strombolian and phreatomagmatic eruptive styles. Taking into account sedimentological constraints seven volcaniclastic lithofacies were distinguished. Type A corresponds to subaerial pyroclastic fall deposits, as is inferred by the common disorganization of the deposit, their breccia-like aspect with presence of large bombs, poor sorting and lack of tractional sedimentary structures. Types B1, B2, B3 and B4 have different volcanic sources and are interpreted to be the product of low-density (dilute) pyroclastic surges, with textural features indicative of fluctuations in flow regime. This interpretation is based on the fabric and grain size of pyroclasts, together with the size and geometry of the internal sedimentary structures. Type C represents a secondary volcanic deposit related to volcanic sediments reworked by transitional hyperconcentrated flows and dilute fluvial processes, having subsequently accumulated in braided fluvial systems. Finally, the Type D is interpreted as an intra-maar scoria/spatter cones related to the development of maars. The most important factors that determined the sedimentation in these basins were orientation of basement faults, paleogeographic and sedimentological controls, style of eruption and volcaniclastic lithofacies type

We study the volcaniclastic lithofacies interbedded between siliciclastic and carbonate sediments of Cenozoic-Quaternary age (8.7 Ma to 7,000 BP) in Argamasilla and Calzada-Moral basins (Central Spain). The siliciclastic and carbonate deposits correspond to fluvio-lacustrine sedimentary environments. The volcanic materials consist of primary and reworked volcaniclastic successions sourced from the Campo de Calatrava Volcanic Field. Pyroclastic deposits are related to monogenetic and small-volume volcanic centres, such as scoria cones, tuff rings and maars, corresponding to Strombolian and phreatomagmatic eruptive styles. Taking into account sedimentological constraints seven volcaniclastic lithofacies were distinguished. Type A corresponds to subaerial pyroclastic fall deposits, as is inferred by the common disorganization of the deposit, their breccia-like aspect with presence of large bombs, poor sorting and lack of tractional sedimentary structures. Types B1, B2, B3 and B4 have different volcanic sources and are interpreted to be the product of low-density (dilute) pyroclastic surges, with textural features indicative of fluctuations in flow regime. This interpretation is based on the fabric and grain size of pyroclasts, together with the size and geometry of the internal sedimentary structures. Type C represents a secondary volcanic deposit related to volcanic sediments reworked by transitional hyperconcentrated flows and dilute fluvial processes, having subsequently accumulated in braided fluvial systems. Finally, the Type D is interpreted as an intra-maar scoria/spatter cones related to the development of maars. The most important factors that determined the sedimentation in these basins were orientation of basement faults, paleogeographic and sedimentological controls, style of eruption and volcaniclastic lithofacies type

[EN] The location of the Late Cretaceous paleoshoreline in the Leonese Area (Iberian Trough, Spain) has been investigated by seismic analysis through isobath and isopach maps. The succession can be divided into two depositional sequences: DS-1 and DS-2. These sequences are composed of fluvial systems at the base, with paleocurrents that flowed eastward and north-eastward. The DS-1 sequence (Late Albian-Middle Turonian) shows intertidal to subtidal and offshore deposits at the top, while the DS-2 sequence (Late Turonian-Campanian) presents intertidal to subtidal, tidal flat and shallow marine and lacustrine deposits at its top. The stratigraphic cyclicity based on systems tracts shows that these two depositional sequences exhibit remarkable eustatic control. Both sequences start at the base with a significant sedimentary supply from fluvial systems, related to eustatic fall episodes, and conclude at the top with transgressive periods. The evolution of the basin reveals the history of base-level changes and associated shifts in depositional trends during successive stages. The deeper sectors of the DS-1 sequence are located towards the northeastern part of the study area while the proximal portion of the basin-margin is located to the southwest. The paleoshoreline is placed in a direction oriented at 120. The variations in thickness are elongated in orientations between 030 and 050 and are mainly related to paleovalleys and tributary fluvial networks that supply sediment through the shoreline. It is possible that these variations may be related to active synsedimentary faults. Depocenters move toward the northeast and east during the DS-2 sequence while the proximal portion of the basin-margin moves to the southwest. The paleoshoreline has an orientation of 155 direction and moves basinward. The isopach maps show a group of corridors oriented at 130-140 and 165-170, interpreted as result of accumulation of sandy bodies such as inter and subtidal bars. The fluvial syst

[ES] El distrito minero de oro Llamas de Cabrera, explotado durante el imperio romano y redescubierto en 2003, se localiza en el flanco norte del Sinclinal de Truchas (Zona Centroibérica, Macizo Varisco Ibérico). Los yacimientos de oro se encuentran en venas de cuarzo post-tectónico encajadas en las capas superiores de la Cuarcita Armoricana y, ocasionalmente en pizarras de la Fm. Luarca (Matte, 1968). Los fluidos mineralizadores fueron equilibrados en gran medida con litologías metamórficas a temperaturas medias-altas (Gómez-Fernández et al., 2012), previamente a su movilización para dar lugar a los yacimientos.

[EN] Boñar Formation (Upper Cretaceous) is a mainly carbonate succession, which outcrops in the North of Duero Basin (Spain). According to the existing data, the Dolomitic Member of this formation appears to be the most suitable for geological storage of CO2. The main objective of this study is to find evidence to support, clarify and specify –at an initial level– the potential of the Dolomitic Member of the Boñar Formation as a geological reservoir. The study covers density, porosity and permeability tests on samples obtained from the outcrop of the succession near the village of Boñar (León). According to the analysis and interpretation of the mentioned petrophysical properties, the porosity of the Dolomitic Member is within the acceptable range for CO2 geological storage, but the permeability values are far too low. This minimizes the possibilities of the Dolomitic Member –and probably of the whole Boñar Formation– to become an appropriate CO2 reservoir., [ES] La Formación Boñar (Cretácico Superior) es una sucesión carbonática que aflora al Norte de la Cuenca del Duero (España). Según datos previos, el Miembro Dolomítico de esta formación es el que muestra características petrográficas más favorables para almacenamiento geológico de CO2. El principal objetivo de este trabajo es el aporte de elementos de juicio que apoyen, clarifiquen y concreten –a un nivel de estudio preliminar– la potencialidad del Miembro Dolomítico de la Formación Boñar como roca almacén. La Formación Boñar (Cretácico Superior) es una sucesión carbonática que aflora al Norte de la Cuenca del Duero (España). Según datos previos, el Miembro Dolomítico de esta formación es el que muestra características petrográficas más favorables para almacenamiento geológico de CO2. El principal objetivo de este trabajo es el aporte de elementos de juicio que apoyen, clarifiquen y concreten –a un nivel de estudio preliminar– la potencialidad del Miembro Dolomítico de la Formación Boñar como roca almacén.