Assessing irrigation performance with comparative indicators: The case of the Alto Rio Lerma Irrigation District, Mexico

Irrigation management / Irrigation scheduling / Water allocation / Water distribution / Case studies / Institutional constraints / Operation / Monitoring / Indicators / Performance indexes / Water rights / Economic aspects / Data collection / Environmental effects / Performance evaluation / Water use efficiency

Chronology of the late Turolian deposits of the Fortuna basin (SE Spain): implications for the Messinian evolution of the eastern Betics

The magnetostratigraphy of the mammal-bearing alluvial fan-fan delta sequences of the Fortuna basin (SE Spain) has yielded an accurate chronology for the late Turolian (Messinian) basin infill. From early to late Messinian (at least between 6.8 and 5.7 Ma), the Fortuna basin records the sedimentation of alluvial-palustrine deposits over a confined shallow basin. Changing environmental conditions in the latest Messinian are illustrated by the retreat of palustrine facies. A rapid progradation of the marginal clastic wedges and the initiation of an efficient basin drainage at 5.8 Ma (lower part of chron C3r) most likely represents the onshore response to the drastic drop of base level taking place during the Messinian salinity crisis. This study further provides improved age estimates for the late Turolian land mammal events in southern Spain. The oldest MN 13 locality in the studied sections is correlated to chron C3Ar at an age of 6.8 Ma. The entry of camels and the murid Paraethomys in southern Spain occurs in chron C3An.1n at 6.1 Ma, and gives further support for land mammal exchange between Africa and the Iberian peninsula prior to the salinity crisis, in good agreement with results from northern Africa [M. Benammi, M. Calvo, M. Pre´vot, J.J. Jaeger, Magnetostratigraphy and paleontology of Ai¨t Kandoula basin (High Atlas, Morocco) and the African-European late Miocene terrestrial fauna exchanges, Earth Planet. Sci. Lett. 145 (1996) 15-29]. The age of the studied sequences provides important constraints on the understanding of the sedimentary evolution of the eastern Betic margin, and shows that previous interpretations of the evaporitic-diatomitic sequences of the Fortuna basin, as being coeval to the late Messinian salinity crisis in the Mediterranean, are not correct. The confinement leading to the emergence of the Fortuna basin occurred in the late Tortonian to earliest Messinian, similar to other intramontane basins in the Betics. Therefore, the inclusion of the Fortuna basin in a hypothetical marine Betic Corridor during the late Messinian is no longer tenable. Ó 1998 Elsevier Science B.V. All rights reserved

Rubefacción e hidromorfismo en suelos de terrezas del Guadalquivir (I) Datos geomorfológicos, fisiográficos y morfológicos

12 páginas.-- 4 figuras.-- 3 perfíles de suelos.-- 6 referencias[EN]: The influence of different factors, sencondary or local, on the pedological rubefaction and hydromorphism processus in underlined. Amongst there factors they have been considered as principal the depth of the limestone accumulation horizon and the microtopography of the area studied, a high correlation between those and the evolution having been found.[ES]: Se pone de relieve la influencia de distintos factores secundarios o locales sobre los procesos edáficos de rubefacción e hidromorfismo. Entre dichos factores se han considerado principales la profundidad del horizonte de acumulación de caliza y la microtopografía del área estudiada, habiéndose encontrado una estrecha correlación entre ellos y la evolución del suelo.Peer reviewe

Rubefacción e hidromorfismo en suelos de terrezas del Guadalquivir (II): Datos físicos, químicos y mineralogicos

14 páginas.-- 5 tablas.-- 16 referencias[EN]: Physical, chemical and mincralogital properties of three profiles belonging to a catena localized in an area relatively smale on the second terrace of the Guadalquivir river within the country of La Rinconada have been studied. On the basis al the properties one deepens into the knowledge of forms distribution and dynamics or iron in the profile in relatíon lo the rubefaction and hydromorphism processus[ES]: Se estudian propiedades físicas, químicas y mineralógicas de tres pedites de suelos pertenecientes a una catena localizada en un arca relativarnente pequeña de la segunda terraza del río Guadalquivir, dentro del término de La Rinconada (Sevilla). Sobre la base de dichas propiedades, se profundiza en el conocimiento de las formas, distribución y dinámica del hierro en el pedil, en relación con los procesos de rubefacción e hidromorfismo.Peer reviewe

Monte Carlo Simulation of Surface De-alloying of Au/Ni(110)

Based on BFS model and using Monte Carlo simulation we confirms the de-alloying in immiscible Au/Ni(110) system, and the critical Au coverage when de-alloying happens is also consistent with experiments. At the same time our simulation show that the structural phase transition will lead to the saturation of the number of alloying Au atoms.Comment: Submitted to Surface Science, 14 Pages, 6 Figure(.eps

The 'Tortonian salinity crisis' of the eastern Betics (Spain)

The late Miocene depositional history of the Lorca and Fortuna basins, both occupying an internal position in the eastern Betics of Spain, is marked by a regressive sequence from open marine marls, via diatomites and evaporites, to continental sediments. Based on facies similarities, these evaporites have often been correlated to the well-known Mediterranean evaporites of the Messinian salinity crisis, although this correlation was never substantiated by reliable chronological data. In this paper, we present an integrated stratigraphy of this regressive sequence which shows that the evaporites of the Lorca and Fortuna basins are entirely of late Tortonian age and as such have no relation with the Messinian salinity crisis. The main phase of basin restriction, resulting in deposition of diatomites and evaporites, took place at 7.8 Ma, while the last marine deposits (massive evaporites of the Lorca basin) are dated at 7.6 Ma. Consequently, this `Tortonian salinity crisis' of the eastern Betics had a duration of approximately 200 kyr, while continental deposition prevailed throughout the entire Messinian as also revealed by the fossil mammal record. The `Tortonian salinity crisis' of the eastern Betics is obviously related to a local phase of basin restriction caused by uplift of the metamorphic complexes at the basin margins, probably in concert with strike-slip activity along SW-NE trending fault systems. The development of a submarine sill is of crucial importance for the increase in salinity because it allows marine waters to continuously enter the basin at the surface while it restricts or prevents the outflow of dense saline waters at depth. Furthermore, we show that evaporite and diatomite cyclicity in these restricted basins is predominantly related to precession controlled circum-Mediterranean climate changes and that glacio-eustatic sea level changes only play a minor role. It is remarkable that the lithological sequence of the Tortonian salinity crisis mimics in many aspects that of the Messinian salinity crisis. This suggests that the diatomaceous facies is an essential part of the lithological sequence associated with basin restriction

El problema de la seguridad pública: una aproximación desde la teoría del Estado de Thomas Hobbes

Analyzes the state from the conception Hobbesian and specifies that it has as its main objective to guarantee the security in the political society, displacing other state goals like the common good, the happiness, the protection of the liberties, etc. that They had relevance in the philosophical-political projects of the classical tradition and of not few contemporary philosophers. The Hobbesian state is minimal in relation to a possible intervention in areas such as social and economic, but expansive with regard to measures to combat insecurity. It proposes that this state and the contemporaries of neoliberal orientation are legitimized by their police function in an international scenario marked by fear and insecurity.Analiza el Estado desde la concepción hobbesiana y precisa que este tiene como principal objetivo garantizar la seguridad en la sociedad política, desplazando otras metas estatales como el bien común, la felicidad, la protección de las libertades, etc. que tuvieron relevancia en los proyectos flosófco-políticos de la tradición clásica y de no pocos flósofos contemporáneos. El Estado hobbesiano resulta mínimo con relación a una posible intervención en ámbitos como el social y el económico, pero expansivo respecto a las medidas para combatir la inseguridad. Propone que este Estado y los contemporáneos de orientación neoliberal están legitimados por su función policial en un escenario internacional marcado por el miedo y la inseguridad

Hipparion dispersal in Europe: magnetostratigraphic constraints from the Daroca area (Spain)

The Nombrevilla section in the Calatayud-Daroca basin (Central Spain) bears one of the best late Aragonian to early Vallesian large and small vertebrate fossil records in Europe, including important findings of the equid Hipparion. Magnetostratigraphic dating of the Nombrevilla section thus provides further age constraints on the timing of Hipparion dispersal in Europe, a bioevent which defines the base of the Vallesian mammal stage. Correlation of the Nombrevilla magnetic polarity stratigraphy to the geomagnetic polarity time scale is supported by the identification of the characteristic long normal chron C5n in the upper half of the section,... (Ver más) in association with early Vallesian (early late Miocene) fossils. The classic mammal fossil site Nombrevilla 1, recording the earliest occurrence of Hipparion, correlates to the lower third of chron C5n, and yields an interpolated age of about 10.7-10.8 Ma. This age is in agreement with magnetostratigraphic dating of earliest occurrences in Siwaliks of Pakistan and some 40Ar/39Ar ages of Mediterranean sites. The youngest pre-Hipparion large mammal fossil record corresponds to Nombrevilla 9, a site wich approximately correlates to chron C5r.1n, at about 11.1 Ma. This result is nearly in conflict with the data from the Vallès-Penedès, where a Hipparion bearing site is correlated to the same chron. In addition, Nombrevilla 9 yields a small mammal assemblage which corresponds to local zone H, a biozone wich was classically correlated to the lower Vallesian. This implies a diachrony of about 300 kyr between the lower boundary of zone H and the first occurrence of Hipparion (base of the Vallesian) in the Calatayud-Daroca basin. Correlation of the Aragonian levels of Nombrevilla 2, 3 and 4 is not yet certain and would require further downward extension of the magnetostratigraphy in a neighbouring section. Nevertheless, we can confidently say these localities are younger than 11.6 Ma

Low-energy neutrino-electron scattering as a Standard Model probe: the potential of LENA as case study

Several proposals for studying neutrinos with large detectors are currently under discussion. We suggest that they could provide a precise measurement of the electroweak mixing angle as well as a probe for new physics, such as non-standard neutrino interactions (NSI), and the electroweak gauge structure. We illustrate this explicitly for the case of the LENA proposal, either with an artificial radioactive source or by using the solar neutrino flux

Late Miocene alluvial sediments from the Teruel area: Magnetostratigraphy, magnetic susceptibility, and facies organization

We present the paleomagnetic dating of the upper Miocene red alluvial to palustrine sequences of the area north of Teruel. The magnetostratigraphy of the Masada del Valle and Masada Ruea sections indicates a minimum age of about 11 Ma to the lowermost sediments post-dating the unconformity over the Mesozoic basement. The overall Miocene sequence represents a retrogradation of the alluvial system, grading upwards into palustrinellacustrine sedimentation. The onset of palustrine deposition is dated in Masada Ruea at about 9.7 Ma. The late Vallesian faunas of Masía del Barbo, of which leve1 2B is the reference locality of biochronozone MNlO, are dated to 9.3 Ma. The anisotropy of magnetic susceptibility (AMS) in the tenigenous sediments suggests that the orientation of the magnetic ellipsoids represents the paleocurrent direction. Paleocurrent interpretations based on AMS data can be used for a better comprehension of the facies arrangement in the Neogene sediments of the Teniel basin