Browsing Geogaceta -- Nº 18, (1995) by Issue Date
Now showing items 1-20 of 54
-
Determinación de los tensores de deformación y esfuerzo en calizas mediante el estudio comparado de poblaciones de fallas y del maclado mecánico de la calcita
(Sociedad Geológica de España, 1995)The strain tensor in limestones has been calculated using the strain-gauge technique (Croshong, 1972). This method is based in the analysis of the mechanical twinning in calcite. In the same outcrops, these-results have ... -
Exhumación alpina del bloque morfotectónico Pedriza - La Cabrera (Sierra del Guadarrama, Sistema Central Español): potencialidad de la termocronometría por trazas de fisión en apatitos
(Sociedad Geológica de España, 1995)The principles of Apatite Fission Track Analysis (AFTA), which allows to decipher the time-temperature paths of apatites since their last cooling below about 110°C are given and one example, from a Pedriza - La Cabrera ... -
Análisis de la fracturación en los afloramientos mesozoicos del suroeste español
(Sociedad Geológica de España, 1995)The Mesozoic outcrops of southwestern Spain show a complex succession of sedimentary and volcanic rocks. Their deposition is related to the first episodes of rifting between Africa and Iberia that took place from the Late ... -
Estudio de plagioclasas de granitoides híbridos del Macizo Ibérico mediante microscopía de Interferencia de Contraste Nomarski
(Sociedad Geológica de España, 1995)Nomarski microscopy has revealed strong zoning in plagioclases of hybrid graitoids of Gerena massif (Seville Range batholith) consisting of oscillatory, hiatus, dendritic and resorption zones which can repeat several times ... -
Preliminary report of seepage mound occurrences in Spain. Comparison with carbonate mounds from the Amargosa Desert, western USA
(Sociedad Geológica de España, 1995)Los seepage mounds son depósitos de geometría dómica debidos a flujo y descarga de aguas subterráneas, estando su posición relacionada con zonas lineales de fractura. Describimos en este trabajo dos ejemplos de este tipo ... -
El límite de las Biozonas Transversarium y Bifurcatus (Oxfordiense Medio) en la Cordillera Ibérica nororiental: discontinuidades y lagunas estratigráficas asociadas
(Sociedad Geológica de España, 1995)A biostratigraphic study of Middle Oxfordian, Transversarium to Bifurcatus Zone rocks in the northeastern Iberian Chain (Spain) has been taken along six detailed sections providing very close ammonite control. The deposition ... -
Icnitas de vertebrados en las facies Buntsandstein (Triásico inferior) del Macizo de Montalbán (Peñarroyas, prov. de Teruel)
(Sociedad Geológica de España, 1995)The discovery of a new outcrop in lower Triassic fluvial sediments with diapsida footprints has been made in the locality of Peñarroyas (Teruel, Spain). There are 19 footprints which 18 has been interpreted as belonging ... -
Paleoesfuerzos alpinos en el borde suroccidental de la cuenca de Madrid (Montes de Toledo)
(Sociedad Geológica de España, 1995)The paleostress analysis are used here to outline the Alpine deformation of the contact between the Toledo Mountains and the Madrid Basin. This limit results from a system of E-W-trending reverse faults, NW-SE-trending ... -
Estructura y metamorfismo del Macizo Hercínico de Rehamna (Meseta Occidental, Marruecos)
(Sociedad Geológica de España, 1995)The structure of the Rehamna Massif, in the Moroccan Hercynian Belt, can be related to the development of a first compressive regime followed by another one of extensional character. The Skhour Nappe and Eastern Rehamna ... -
Presencia de la amalgama Au-Ag-Hg en el Cinturón Piritico Ibérico, mina de la Zarza, (Huelva)
(Sociedad Geológica de España, 1995)In the La Zarza Mine gold is found as native gold and as Au-Ag-Hg amalgam first discovered in the Iberlam Pyritic Belt. The average amalgam composition obtained by Microprobe Data analyses is A u 03(/ \ g 052Hg0 W. This ... -
Estudio mineralógico de las variscitas y turquesas silúricas de Punta Corveiro (Pontevedra, España)
(Sociedad Geológica de España, 1995)In this paper we resume the geological and essential mineralogical characteristics of the phosphated mineralization found in the Silurian of W sector in the Pontevedra province, in "Punta Corveiro", south of La Lanzada ... -
Precisiones sobre la bioestratigrafía de las Clavatoraceas del Valanginiense de la Sierra del Pozo (Provincia de Jaén, SE de España)
(Sociedad Geológica de España, 1995)Some Clavatoraceae species have been determinated at the top of the Upper Berriasian-Lower Valanginian depositional sequence. Age determination is highly consistent with dating obtained through Foraminifera studies and ... -
Problemática del uso de los tomamuestras de succión en el estudio de la ZNS en el polje de Zafarraya (Granada y Málaga)
(Sociedad Geológica de España, 1995)In the polje of Zafarraya, two experimental sites have been Installed and equipped with seven porous ceramic cups each, with depths of between 0.25 and 3 m. The main problems related to preparation involve washing the cups ... -
Variación de la fábrica del cuarzo en el manto de Los Reales (Cordilleras Béticas)
(Sociedad Geológica de España, 1995)Quartz fabrics from tectonites belonging to the metamorphic sequence of the Los Reales nappe, in the Betic cordillera (SE Spain), provide a fabric zoning which mainly reflects different temperature conditions during plastic ... -
Tipología de los granitoides y rocas asociadas del complejo migmatítico de la Punta deis Farallons (Cap de Creus, Pirineo Oriental)
(Sociedad Geológica de España, 1995)The Punta dels Farallons migmatitic complex (Cap de Creus, eastern-Pyrenees) consists of an association of partially migmatized sillimanite schists, small heterogeneous bodies of granitoids and quartz-gabbros, and a ... -
Origen de las piritas de la cuenca de Cameros, (La Rioja)
(Sociedad Geológica de España, 1995)The pyrite mineralizations of the Cameros basin has been traditionally interpreted as diagenetic. On the basis of trace element content, S isotopes study, pyrite inclusions and geologic observations, the pyrite crystals ... -
Evolución sedimentaria reciente de las Tablas de Daimiel (Ciudad Real)
(Sociedad Geológica de España, 1995)Two sedim entary events have been distinguished in the recent evolu tio n o f the present Tablas de Daimiel National Park. The older one is characterized by the presence of siliceous sands and silts, and mudstones; the ... -
Abanicos aluviales de la cuenca norte de Madrid. Análisis matemáticos
(Sociedad Geológica de España, 1995)Aluvial fan deposits in the Tertiary North Basin of Madrid have been studied by geophysical logging in several hidrogeological boreholes. Thus, spectral and statistical analysis are used as tools to confirm the sedimentological ... -
Depósitos fluviales paleógenos en el sector suroriental de la cuenca del Ebro: tipos de incisión y relleno
(Sociedad Geológica de España, 1995)The outcrops of Scala Dei (Colombo, 7 980) and Guadalope-Matarraña (Cabrera, 1983) alluvial systems are located in the SE sector of the Ebro basin. These alluvial systems were developed during the Palaeogene between the ... -
Expansión de un sistema lacustre en el tránsito Jurásico Cretácico (Cubeta de Aliaga, Prov. Teruel)
(Sociedad Geológica de España, 1995)In the Aliaga subbasin (Central Iberian Range) crops out a mainly calcareous serie corresponding to the Tithonic-Berriasian Villar Arzobispo Formation. There are important litological differences between this serie and ...