The impact of man on the morphodynamics of the Huelva coast (SW Spain)

The Huelva coast is composed by large sandy beaches and spits, only interrupted by the presence of the estuarine mouths of the Guadiana, Piedras, Tinto-Odiel and Guadalquivir which are in an advanced state of sediment infilling. The morphology and processes of the Huelva coast are mainly linked to tidal regime, wave action, coastal-drift currents, fluvial dynamics, climatic change and anthropogenic activity. In the last five decades anthropogenic activity has modified the natural dynamics by the construction of jetties, docks, harbour and coastal developments. The main consequences have been the interruption of the sedimentary bypassing caused by an active west-to-east littoral drift, the modification of the tidal regime, the wave refraction-diffraction scheme and the intensification of the littoral erosive processes. All these effects will increase with the slow sea-level rise, close to 0.6 cm per year, which will induce a higher efficacy of the erosional events. A future retreat of about 10-15 m of the coastline is estimated.La costa de Huelva esta constituida por extensas playas y flechas litorales, interrumpidas por la presencia de grandes estuarios (Guadiana, Piedras, Tinto-Odiel y Guadalquivir) en un estado avanzado de colmatación. La morfología y los procesos de la costa se deben principalmente a una serie de factores: régimen mareal, olas, corrientes de deriva, dinámica fluvial, cambio climático y la actividad antrópica. En las últimas cinco décadas la actividad antrópica ha modificado la dinámica natural debido a la construcción de espigones, escolleras, puertos y urbanizaciones. Las principales consecuencias de esta actividad han sido la interrupción del trasvase de sedimentos del Este hacia el Oeste por la corriente de deriva litoral, la alteración del régimen mareal, la modificación de los procesos de refracción-difracción de olas y la intensificación de los procesos erosivos. Todos estos efectos se verán incrementados con el paulatino ascenso del nivel del mar en el Golfo de Cádiz, del orden de 0,6 cm anuales, repercutiendo en una mayor eficacia de los eventos erosivos. Se estima una pérdida del orden de 10-15 m en el perfil de las playas

La Formación Areniscas de Ciudad Rodrigo: Ejemplo de sedimentación controlada por paleorrelieves (Eoceno, fosa de Ciudad Rodrigo)

[ES] Se define formalmente como Formación Areniscas de Ciudad Rodrigo a la Unidad litoestratigráfica comprendida entre los relieves paleozoicos de las Sierras de Torralba, Camaces, Peronilla y Carazo y los bordes del sureste de la Fosa de Ciudad Rodrigo. Esta Formación es el resultado del desmantelamiento de áreas madres metamórficas y granitoides ubicadas al NO, O y SE. La disposición convergente de las paleocorrientes y la existencia de paleorrelieves al NE, señalan la configuración paleogeográfica de una cuenca endorreica. Esta cuenca fue rellenándose por los sedimentos arrastrados por sistemas de abanicos aluviales. La ordenación actual de los depósitos, hace suponer que el desarrollo del sistema sedimentario estuvo controlado por paleorrelieves que cerraban al borde NE de la cuenca durante el Eoceno.[EN] In the southeastern Ciudad Rodrigo there is a conspicuous sandstone unit that has been usually refered to as «Serie» de Ciudad Rodrigo. The purpose of this paper is to define this Lithostratigraphic Unit: Ciudad Rodrigo Sanstone Formation. This Unit consist of clastic sediments derived from the weathered metamorphic and plutonic rocks placed in NW, SW and S of the basin. Paleocurrent measurement reveal a convergent pattern which coupled with the existent paleo reliefs towards the NE, suggest and endorheic basin that was progresively filled up by alluvials fans sediments. From the analysis of the present day distribution of deposits it is proposed that the development of alluvials fans was controlled by the paleo-reliefs that closed the Noreastern edge of the basin during Eocene times

Examination of the Feynman-Hibbs Approach in the Study of NeN_N-Coronene Clusters at Low Temperatures

Feynman-Hibbs (FH) effective potentials constitute an appealing approach for investigations of many-body systems at thermal equilibrium since they allow us to easily include quantum corrections within standard classical simulations. In this work we apply the FH formulation to the study of Ne$_N$-coronene clusters ($N=$ 1-4, 14) in the 2-14 K temperature range. Quadratic (FH2) and quartic (FH4) contributions to the effective potentials are built upon Ne-Ne and Ne-coronene analytical potentials. In particular, a new corrected expression for the FH4 effective potential is reported. FH2 and FH4 cluster energies and structures -obtained from energy optimization through a basin-hoping algorithm as well as classical Monte Carlo simulations- are reported and compared with reference path integral Monte Carlo calculations. For temperatures $T> 4$ K, both FH2 and FH4 potentials are able to correct the purely classical calculations in a consistent way. However, the FH approach fails at lower temperatures, especially the quartic correction. It is thus crucial to assess the range of applicability of this formulation and, in particular, to apply the FH4 potentials with great caution. A simple model of $N$ isotropic harmonic oscillators allows us to propose a means of estimating the cut-off temperature for the validity of the method, which is found to increase with the number of atoms adsorbed on the coronene molecule

A glimpse at Ethology in Latin America

The state of the art of Ethology in five Latin America countries is briefly presented here. The overall outlook regarding research laboratories and themes is promising: the community is numerous, active and there are topics addressing all aspects of animal behavior, especially in large countries like Brazil and Argentina. Ethology as an undergraduate discipline is generally a subcategory of Biology, being taught mainly at Zoology/ Psychology/ Ecology/ Agriculture Courses and at Medical Veterinary Schools, often as an eligible discipline. Ethology as a formal major Graduate Program is rare and mainly restricted to Brazil.Facultad de Ciencias Naturales y Muse

A glimpse at Ethology in Latin America

The state of the art of Ethology in five Latin America countries is briefly presented here. The overall outlook regarding research laboratories and themes is promising: the community is numerous, active and there are topics addressing all aspects of animal behavior, especially in large countries like Brazil and Argentina. Ethology as an undergraduate discipline is generally a subcategory of Biology, being taught mainly at Zoology/ Psychology/ Ecology/ Agriculture Courses and at Medical Veterinary Schools, often as an eligible discipline. Ethology as a formal major Graduate Program is rare and mainly restricted to Brazil.Facultad de Ciencias Naturales y Muse

Roadmap on dynamics of molecules and clusters in the gas phase

This roadmap article highlights recent advances, challenges and future prospects in studies of the dynamics of molecules and clusters in the gas phase. It comprises nineteen contributions by scientists with leading expertise in complementary experimental and theoretical techniques to probe the dynamics on timescales spanning twenty order of magnitudes, from attoseconds to minutes and beyond, and for systems ranging in complexity from the smallest (diatomic) molecules to clusters and nanoparticles. Combining some of these techniques opens up new avenues to unravel hitherto unexplored reaction pathways and mechanisms, and to establish their significance in, e.g. radiotherapy and radiation damage on the nanoscale, astrophysics, astrochemistry and atmospheric science

Silicification contemporaine à la sédimentation dans l'unité basale du paléogène du bassin du Duero (Espagne)

The Paleogene base unit of the Duero basin, dated as Paleocene, is a sedimentary series of fluvial origin. Of the four members of which the unit is composed, the two uppermost are formed by a series of cyclothem which show an intense silicification. The silicification is of edaphic origin arid is shown by opal cementation. The silicif ication process has not been a simple one but of a multiple nature, and each one has occurred after the cyclothem had been deposited.L'unité basale du Paléogène du bassin du Duero, datée comme Paléocène, est une série sédimentaire d'origine fluviale. Des quatre membres qui composent l'unité, les deux supérieurs sont formés par une succession de cyclothèmes qui présentent une si-licification intense. La silicification a une origine pédologique et se manifeste par une cimentation d'opale. Le processus de silicif ication n'a pas été unique mais multiple, avec un épisode après le dépôt de chaque cyclothème.Blanco J.A., Cantano M. Silicification contemporaine à la sédimentation dans l'unité basale du paléogène du bassin du Duero (Espagne). In: Pétrologie des altérations et des sols. Vol. II : Pétrologie des séquences naturelles. Colloque international du CNRS, Paris 4-7 juillet 1983. Strasbourg : Institut de Géologie – Université Louis-Pasteur, 1983. pp. 7-18. (Sciences Géologiques. Mémoire, 72

Silicification contemporaine à la sédimentation dans l'unité basale du paléogène du bassin du Duero (Espagne)

The Paleogene base unit of the Duero basin, dated as Paleocene, is a sedimentary series of fluvial origin. Of the four members of which the unit is composed, the two uppermost are formed by a series of cyclothem which show an intense silicification. The silicification is of edaphic origin arid is shown by opal cementation. The silicif ication process has not been a simple one but of a multiple nature, and each one has occurred after the cyclothem had been deposited.L'unité basale du Paléogène du bassin du Duero, datée comme Paléocène, est une série sédimentaire d'origine fluviale. Des quatre membres qui composent l'unité, les deux supérieurs sont formés par une succession de cyclothèmes qui présentent une si-licification intense. La silicification a une origine pédologique et se manifeste par une cimentation d'opale. Le processus de silicif ication n'a pas été unique mais multiple, avec un épisode après le dépôt de chaque cyclothème.Blanco J.A., Cantano M. Silicification contemporaine à la sédimentation dans l'unité basale du paléogène du bassin du Duero (Espagne). In: Pétrologie des altérations et des sols. Vol. II : Pétrologie des séquences naturelles. Colloque international du CNRS, Paris 4-7 juillet 1983. Strasbourg : Institut de Géologie – Université Louis-Pasteur, 1983. pp. 7-18. (Sciences Géologiques. Mémoire, 72

Introduction to the analysis of flood hazards on the margins of estuarine areas: The case of the towns adjacent to the Ría de Huelva (SW Spain)

Floods are natural events that occur in depressed areas. These phenomena can be related with extreme river discharges in fluvial valleys or with wave surges in coastal areas. In estuarine areas, both causes can coincide during stormy periods. The Ría de Huelva is the common estuary of Tinto and Odiel rivers, which are extremely irregular because of their pluvial character. The slatey-quartzitic character of the drainage area induces an immediate response of the fluvial flow to the rains. This estuary is submitted to a mesotidal regime, with a mean tidal range of 2.0 metres, but with extreme equinox high waters that can reach 1.7 metres over the mean tide level (74 cm. over the mean high waters). Meteorologic surges caused by low pressures and winds blowing from the south to the coast can increment the water level near to 1 m. over the tidal level. Strong rains and meteorologic surges occur at same time during Atlantic storms. When these storm coincide with equinox high tides the towns located at the margins of the estuary are normally floode

Karstic processes in the calcarenite formation of Niebla (Huelva, SW Spain)

4 páginas, 2 figuras, 1 fotografía, 10 referencias.-- 21ª Sesión Científica, Huelva, 1996.The development of a covered karst in the Miocene calcarenite formation in the N area of Niebla (Huelva) has been studied. The cover consists of sediments of Quaternary terraces of the River tinto (T9, T8, T7 and T6), and to a lesser degree, fragments of Mio-Pliocene clays ("blue marls"). Solution if the calcarenite has originated vertical pipes of varying size evolving in the top to form funnerl-shaped channels of preferential solution.Peer reviewe