Geogaceta -- Nº 31, (2001)

Permanent URI for this collectionhttps://hdl.handle.net/10272/9380

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Trazas afines a Imbrichnus wattonensis HALLAM de edad Albiense en el Prebético de Alicante (Serra Celada)
(Sociedad Geológica de España, 2001) Caracuel, Jesús Esteban; Monaco, Paolo; Yébenes, Alfonso; Giannetti, Alice
Albian trace fossils related to Imbrichnus wattonensis HALLAM were studied in the "Prebetico de Alicante". Meniscate backfilling with imbricated sandy/ruditic clasts characterized this ichnogenus with regard to Taenidium., and other comparable resting traces. It is proposed a crustacea as the probable trace maker, more likely than a bivalve or annelid
The geometry and kinematics of enclaves in sheared migmatites from the Evora Massif, Ossa-Morena Zone (Portugal)
(Sociedad Geológica de España, 2001) Francisco Pereira, M.; Brandáo Silva, J.
In the Montemor-o-Novo high-grade metamorphic terraines of western Ossa-Morena Zone (Portugal), sheared migmatites display a wide variety of distinct mesoscopic structures. Relationships of leucosome-melanosome layering and rotated enclaves allowed determination in which direction the tectonic movement occurred. We proposed non-coaxial progressive deformation to explain how the fabric elements moved during D2 sinistrai shearing
Técnicas experimentales para el análisis de la actividad bioerosiva de Patella rustica Linnaeus, 1758 (Mollusca; Gastropoda; Patellidae) del litoral rocoso de Mallorca (Mediterráneo occidental)
(Sociedad Geológica de España, 2001) Villanueva, G.; Pons, G. X.; Fornós Astó, Joan J.
Bioerosion is the biological breakdown of hard substrates by boring, grazing, etchting and abrading organisms. Many marine intertidal gastropods, such as limpets, contribute to the erosion by grazing rock substrate in the search for algal food, leaving distinctive marks on the surface of the rock. The present work focuses on the laboratory characterisation and the description of the scratches leaved in an artificial surface (dental wax plates) by the Mediterranean limpet Patella rustica in their feeding activity
Relaciones entre la hidrología subterránea y la estructura geológica en la Sierra de Tramuntana de Mallorca (Islas Baleares)
(Sociedad Geológica de España, 2001) Gelabert, B.; Säbat, F.
The overall structure of the island of Mallorca consists of a set of horsts and grabens which are bounded by Upper Miocene-Quaternary listric normal faults. Horsts are segments of a Lower Miocene thrusted and folded belt and constitutes the Sierras. The basins developed at the grabens, which are filled by Upper Miocene-Quaternary sediments. Groundwater flows from the horsts to the grabens. At the horsts adjacent aquifers exists because of its geological structure (imbricate thrust system), whereas at the grabens aquifers are superposed due to the horizontal sedimentary infilling. Major springs, very important for water supply to Palma, are located at the listric normal faults
Prueba de Radiolocalización y Radioenlace entre Candanchú y el Túnel Ferroviario Internacional de Canfránc (Huesca)
(Sociedad Geológica de España, 2001) Ayuso, N.; Cuchí Oterino, José Antonio; Villarroel Salcedo, J. L.
A new device for underground radiolocation and radio conection was tested betweeen the railway tunnel of Canfranc and the sky ressort of Candanchu. The results provide a radiolocation through 500 m. of limestone and wet shale, and a radioconection through 890 m. of karstified limestones. Giving the relation between the electrical conductivity of the rock and the attenuation of the signal, the results suggest that the device could be used as a geophysical tool
Procesos de erosión acelerada en la cuenca alta del río Monachil (Granada)
(Sociedad Geológica de España, 2001) Gisbert, Josep; Vallejos, Ángela; Pulido Bosch, Antonio; Martín Rosales, Wenceslao
The conditioning of the Skiing Station of Sierra Nevada (1990-1996) produced a high impact on river Monachil headwaters, mainly on geomorphology and surface waters. Protecting and correcting measures applied during station repairs have made very good results. Such measures succeeded in decreasing total sediment load, generated when former balance broke; the drainage of the slopes also avoided the formation of landslides
Procesos de karstíficación polifásica en las canteras de Crema Marfil (Pinoso, Alicante). Aplicación a la explotación de rocas ornamentales
(Sociedad Geológica de España, 2001) Cañaveras, J.C.; García del Cura, María Angeles; Sánchez Moral, S.; Muñoz Cervera, M. C.; Ordóñez, Salvador
Complex speleothem networks have been recognised in the quarries of the commercial marble Crema Marfil (Paleogene limestones, Monte Coto Pinoso, Alicante). The characterisation of these speleothems (mineralogy, petrography, stable isotopes) has enable us to discriminate different phases of speleothem formation in terms of paleotemperature or structural control. U/Th dates of some of these phases are 178,7± 15,6 Ka, 34,4+1,7 Ka y 33,7±3,4 Ka. A seismo-tectonic event has been recorded and dated (33-34Ka) by the study of speleothems. The recognition and characterisation of speleothem networks can be considered as a useful tool in the design of exploitation strategies of dimension stones
Primeros datos paleobotánicos y palinológicos de una flora miocènica procedente de la unidad intermedia en el sector central de la Cuenca de Madrid
(Sociedad Geológica de España, 2001) Fernández Marrón, M. T.; Fonollá Ocete, J. F.; Jiménez Rodrigo, J. C.
For the first time macroremains flora of Miocene from Madrid are studied. On the basis of this palaeobotanical and palynological studies more over 110 taxons have bee distinguished. The plant association is very hetogeneous with a mixture of elements from several environments (mountainous, fluviatile, lacustrine areas etc.) according to others previous sedimentolgical, geochemistry and faunistics data
Paleosalinidad y tamaño de las valvas del ostrácodo Cyprideis torosa (Jones) en niveles del Pleistoceno inferior y medio
(Sociedad Geológica de España, 2001) Ortiz, José Eugenio; Torres, Trinidad de; Demoustier, A.; Castroviejo Bolibar, R.; Morena, M. A. de la; Llamas, F. J.; Lucini, M.
The correlation between the size of Lower and Middle Pleistocene Cyprideis torosa Cores) ostracode valves and paleosalinity reveal the existence of a direct relationship though little significant. This observation suggest that in spite of the two areas of Cullar-Baza Basin, where the ostracodes have been picked, were controlled under similar general paleodimatic conditions, the particular and local paleogeographical conditions had a major influence not only in the specific diversity but also in the morphology of the ostracodes
Modificaciones de los parámetros ambientales de la Cueva de Nerja provocadas por la entrada de visitantes
(Sociedad Geológica de España, 2001) Carrasco Cantos, Francisco; Liñán Baena, Cristina; Durán Valsero, Juan José; Andreo Navarro, Bartolomé; Vadillo Pérez, Iñaki
In Nerja Cave, since 7 993 to present time, the values of underground atmosphere parameters (air and rock temperature, relative humidity, C02 concentration and number of visits) have been controlled to verify the anthropogenic modifications that suffer the cave due to the tourist visits. A variation in the environmental parameters related to the opening and closure of the cave to visits is observed every day of the year. During some days on July, and coinciding with the Music and Dance Festival, a different evolution of measured parameters have been verified in one of the chamber, due to the high number of spectators inside the cave (~ 800 persons). This affection happens during a period of time when the cave is normally dosed, and in which a total recovery of the background is reached previously to the daily opening of the cave. Anthropogenic modifications produced during the Festival have a temporal cumulative effect, but totally disappear within one week
Los materiales del tránsito Triásico-Jurásico en la región de Villaviciosa (Asturias, España). Caracterización palinológica
(Sociedad Geológica de España, 2001) Barrón, E.; Gómez, J. J.; Goy, Antonio
A lithostratigraphic and palynologic study of the sediments corresponding to the Triassic-Jurassic transition at the Bárzana section, located in the Villaviciosa region (Asturias), has been carried out. Four lithostratigraphic units have been distinguished: A) Black and maroon lutites with evaporites Unit; B) Well bedded dolomites and limestones Unit; C) Lutites, evaporites and carbonates Unit, and D) Grey lutites and carbonate breccias Unit. Samples containing fossils of pollen and spores have been collected in successive levels. The 0 level, with Corollina meyeriana as dominant element, associated to Ovalipollis cf. pseudoalatus, and in neighbouring sections also with Rhaetipollis germanicus and Cerebropollenites pseudomasulae, can be considered as Triassic (Rhaetian). Level 1 8, with Cyathidites minor and Todisporites minor, associated to Corollina torosus and in adjacent areas to Ischyosporites variegatus and Cerebropollenites mesozoicus is Lower Jurassic in age. The biochronostratigraphic analysis indicate that the levels of the upper portion of the A Unit are Rhaetian. The Triassic-Jurassic boundary should be located inside the 8 Unit, below the level equivalent to the lumachellic bed which furnished a specimen of Caloceras pirondi (Reynés) south of Avilés. The sampled level at the base of the C Unit is considered as Hettangian by the persistence of Rhaetipollis germanicus Schulz
La Sierra de Cártama: Pliegue con actividad reciente en las Béticas Occidentales (Hoya de Málaga)
(Sociedad Geológica de España, 2001) Capote, Ramón; Insua Arevalo, Juan M.; Martínez Díaz, J. J.; Martín González, Fidel; Tsige, Meaza
In this work is shown how an active fold (the Sierra de Cartama fault) is marked by the drainage pattern and topography, besides of structural data. The Sierra de Cartama fold is an asymmetric fold with double plunge and determines the shape of an elongated saw in the Western Betic Chains (South of Spain). Watching the drainage patterns, it can be noticed how streams and creeks round the saw. The uplift of the saw raise the valleys steeply, even leaving a hanging valley ("wind gap ") at the western part of the structure. Regarding to these observations, the lateral propagation of the fold seems to be toward the west. The proposed structure implies the existence of a compressive neotectonic activity in the zone. The compressive horizontal direction is N10e-30eW, perpendicular to the fold axis. In this tectonic environment it could be possible to interpret a reverse fault in deep associated with the fold growth
La sección Messiniense - Plioceno de Crevillente (Cordillera Bética oriental): expresión de la crisis de salinidad del Mediterráneo
(Sociedad Geológica de España, 2001) Soria, Jesús M.; Yébenes, Alfonso; Caracuel, Jesús Esteban
A composite stratigraphic section in Crevillente (eastern Betic Cordillera) is studied. It represent a complete stratigraphical and paleontological record of the Messinian and Lower Pliocene. Two discontinuity surfaces related to the Mediterranean salinity crisis are analysed: a intra-messinian surface which coincides with a sea-level fall leading to the emergence of this area far from marine influences; and an uppermost Messinian unconformity, with strong erosionaI character, overlied by marine Lower Pliocene transgressive deposits
Interpretación geocronológica de la karstificación en el entorno del Sistema Central español a partir de los yacimientos paleontológicos asociados
(Sociedad Geológica de España, 2001) Barea, José; Arribas, A.; Durán Valsero, Juan José; López Martínez, Jerónimo
A review of previously published palaeontological data, jointly with new discovered fossils, allowed to stablish that the older fossils into detritic endokarstic deposits in the studied area are of Lower to Medium Pleistocene age, being located in caves of the southern side of the Central Range. In caves of the northern side, fossils with ages from Medium Pleistocene have been found. The mentioned chronological difference could be due to the fact that the endokarst at the southern side of the Spanish Central Range was earlier that in the northern side accessible to animal species that used it as a refuge
Influencia de los episodios lluviosos recientes en la recarga del acuífero del Ventos-Castellar (Alicante)
(Sociedad Geológica de España, 2001) Andreu Rodes, José Miguel; Delgado, José; García Sánchez, Ernesto; Pulido Bosch, Antonio; BeIlot, J.; Chirino, Esteban; Ortiz de Urbina, J. M.
The Ventós-Castellar aquifer is a small karstic system located in the province of Alicante (Spain). An exhaustive monitoring is being acomplished on this aquifer to quantify its natural recharge. The study of the piezometric data shows the great influence that exercise the climatic factors in the aquifers with areas of recharge of small extension. The analysis ofthe pluviomectric data and the drop ot the water leve has allowed to establish that those rainfalls above 7 7 mm reach the saturated zone and become effective rainfalls. During the last years we have analyzed 2 events of recharge; theirs infiltration rates have been between 5 and 8% of the total measured rain
Implicaciones geomorfológicas en suelos y vegetación para el análisis del «Paisaje Natural protegido de El Rebollar» (Sierra de Gata, Salamanca, España)
(Sociedad Geológica de España, 2001) González Hernández, F. M.; Goy, José L.; Sanz, J. M.; Forteza, J.; Barrera, I.; Zazo, C.; Bustamante, I. de; Villota, I.; Sanz, R.
Two kinds of environmental cartographies have been elaborated (synthetic) starting from selected physical parameters: maps of homogeneous units and of natural units that have as last end the evaluation of the Protected Natural Landscape of "El Rebollar. The importance of the geomorphology in the distribution of the soils and vegetation, is manifested in the different natural units, which are characterized by the combination of the homogeneous units (geomorphology and litology) and the vegetation (related with climate), due to these parameters define tlie factors soil formation. On the other hand these natural units have been represented as a synthetic profile standing out the most significant relationships between the geomorphology and the soils
Geometría y Cinemática de Fallas recientes en el margen septentrional del mar de Alborán (sector de Maro, provincia de Málaga)
(Sociedad Geológica de España, 2001) Soto, Juan I.; Manzano, F. J.
The more recent structures in the northern continental margin of the Alboran Sea are NW-SE high-angle normal faults, oblique to the present coastal line and also to the actual crustal thinning pattern. The geometry and kinematics, with particular emphasis on the fault linkage patterns, of two of these recent faults with a preserved fault-scarp, the Las Alberquillas (av. 136/69° SW) and the Maro (av. 149/58° NE) faults, have been studied. The Maro fault is formed by several, small, and non-cylindrical fault segments (< 500 m length) frequently displaced by transfer faults, whereas the Las Alberquillas fault is formed by two long and planar fault segments (total length~ 3800 m), linked by a narrow en-echelon step, thus suggesting a major displacement in this master fault (estimated total displacement of the fault= 38 m). The maximum displacement in the Las Alberquillas fault occurs near its SE tip line, therefore suggesting the overlapping interference with a close and related synthetic normal fault in relay towards the SE in the Alboran Sea. Kinematic data on fault surfaces indicate a normal oblique sense of movement of these faults (rake of the main striae > 60°), being dextral and sinistral in the Las Alberquillas and the Maro faults, respectively. Other, secondary striae, with a right- or left-lateral sense of displacement occurs also locally near major corrugations in these faults. Average fault plane solution in both faults results in a NNE-SSW subvertical compression (P ax/s= 66/033° and 77/232°) and subhorizontal extension (T axis= 23/231° and 13/060°). Last fault slip occurred probably during the lower Pleistocene (-800 ka), on the basis of the geometrical relationships with alluvial-fan deposits and radiometric data
Funcionamiento hidrodinámico del epikarst de la Cueva de Nerja (Málaga)
(Sociedad Geológica de España, 2001) Andreo Navarro, Bartolomé; Liñán Baena, Cristina; Carrasco Cantos, Francisco; Vadillo Pérez, Iñaki
The Nerja Cave allows to study the hydrodynamic functioning of the epikarst of the aquifer in which it is developed. The hydrograph of the drip water inside the Cave, versus the precipitations, and the application of the correlatory and spectral analysis to the long series of data precipitation-dripwater flow, shows the inertial behaviour of the epikarst and the importance of the water stored in its hydrodynamic behaviour. The hydrochemical information, particulary the use of K* and ,aO content, confirms these results
Folding development in the Penibetic Units around the western front of the Alboran Domain (Betics)
(Sociedad Geológica de España, 2001) Balanyá, Juan Carlos; Luján, María; Crespo Blanc, Ana
Miocene shortening within the Penibetic Units (South Iberian Domain) near the western end of the Alboran Domain (Betics hinterland) developed in two phases with different morphologic and structural characteristics. F1 folds are angular, asymmetrical, NW- to SW-vergent, and early-to-middle Miocene in age; they develop a widely distributed spaced cleavage, f, folds, late Miocene in age, result in upright or box shaped, kilometric-scale folds with no associated cleavage. The spatial zonation of the F, folding style suggests that the folds were partially generated by shearing during the overthrusting of the Alboran Domain
Fases de karstificación y sedimentación endokárstica pliopleistocenas en el mediterráneo occidental: evolución de la Cueva de Nerja (Málaga, sur de España)
(Sociedad Geológica de España, 2001) Durán Valsero, Juan José; López Martínez, Jerónimo; Andreo Navarro, Bartolomé; Carrasco Cantos, Francisco; Jiménez de Cisneros, C.; Caballero, E.; Julià, Ramón
Evidence of several phases of karstification and sedimentation in Nerja Cave (Malaga, southern Iberian Peninsula) is pointed out. The mentioned phases could be representative of the Plio-Quaternary endokarstic evolution in the western Mediterranean region. The oldest phase is Pliocene and suposes the formation of important underground holes, being possibly associated to a relatively long period of subtropical climate. During the Pleistocene, several phases of speleothems formation are identified, being separated one of the other by no-chemical sedimentation or erosive periods. Late, in the Medium Pleistocene and in the Upper Pleistocene the periods of speleothems growth correspond to warm isotopic stages of the oceanic sedimentary record. Erosive processes or detritic sedimentation in the endokarst occur during cold periods. The Holocene includes periods of chemical precipitation in the endokarst, in coincidence with the climatic optimum, clearly more humid in northern Africa ca. 7-6 ka.

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