The last deglaciation in the Picos de Europa National Park (Cantabrian Mountains,northern Spain)

A sedimentological and geochemical study of the Lago Enol sequence (Cantabrian Mountains, northern Spain), together with detailed geomorphological mapping, provides a first record of glacier evolution and climate change over the last 40 ka in the Picos de Europa National Park. The Enol glacier retreated from its maximum extent prior to 40 ka BP as demonstrated by the onset of proglacial lacustrine sedimentation in two glaciated depressions: the Comella hollow to the north (before 40 ka BP) and the Lago Enol (before 38 ka BP). These results support previous evidence that the maximum extent of southern European glaciers occurred earlier than in northern Europe. Alternation of homogeneous and laminated proglacial sediments during the glacier retreat illustrate a dynamic glacial evolution during the Marine Isotope Stage (MIS) 3 (40–26 ka BP). A slight warming is detected at 26 ka ago with the change from proglacial sediments (in a lake located in contact to the glacier) to glaciolacustrine sedimentation (in a non‐contact or distal lake). Finally, the onset of organic‐rich sediments took place at 18 ka ago. This last transition occurred in two phases, similarly to the North Atlantic Last Termination, suggesting a link between North Atlantic Deep Water formation oscillations and palaeohydrological variability in the Cantabrian Mountains. Copyright © 2009 John Wiley & Sons, Ltd.     

Subsoil zoning of Mexico City using qualitative relationships between soil strength and electrical resistivity

Summary The seismic events occurring on 19 and 20 September 1985, whose epicentre was located in the coastal region of Michoacan, Mexico, produced tremendous damage in Mexico City. As a result of these losses the civil authorities of the city decided to study and evaluate the mechanical characteristics of the subsoil. To achieve this, it was necessary to drill several boreholes to obtain needed geophysical and geotechnical information. The geophysical method of electrical resistivity was the most appropriate to the research. This method enabled us to understand the structure and soil characteristics of the Mexican Valley.     

Estimation of diffusion constants by observations of isokinetic effects: a test for radiogenic argon and strontium

A method of estimating unknown diffusion constants, by testing isokinetic effects, is briefly outlined. The calculated Ar^rad and Sr^rad diffusion constants agree well with experimental data. The employment of the method is suggested for the setting up of diffusion experiments.     

Relationship between some trace elements and magmatic processes

Relationships between magmatic differentiation, volcanological evolution and occurrence of some trace elements have been pointed out by a petrographic and volcanological study of the Quaternary magmatic products of the Northern Latium alkali-potassic volcanoes (Sabatini, Vico, Vulsini).Several hundred analyses of U, Th, Be, Zr, Rb, Sr have been carried out. The above elements are contained in exceptional quantity in the examined alkaline rocks. The distribution pattern of these elements helps for a better understanding of some types of differentiation and, above all, allows to identify the processes related to the uplift and outflow of magmas which are undetectable with the usual petrochemical methods.In particular, the trace elements considered allow us to distinguish a deepseated magma evolution from superficial differentiations related to the volcanic conditions. Moreover, a loss of alkalies from the upper levels of the magmatic chambers has been ascertained which determines peculiar deformations in the normal petrogenetic trends.-- (: Sabatini, Vico, Vulsini). , . .

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Zusammenfassung Das petrographische und vulkanologische Studium der quartären Vulkanite der Mediterranen Sippe des nördlichen Latiums (die Vulkane Sabatini, Vico und Vulsini) haben uns die Gelegenheit gegeben, die Verhältnisse zwischen Magmenentwicklung, vulkanologischer Evolution und Verteilung einiger Spurenelemente zu bestätigen.Zu diesem Zweck sind Hunderte von Analysen von U, Th, Be, Zr, Sr, Rb — Elemente welche in ungemein großen Mengen in den untersuchten alkalischen Gesteinen enthalten sind — vorgenommen worden. Das Studium der Verteilung dieser Elemente hat ein gründliches Verstehen einiger Differentiationstypen erlaubt, und vor allem den Ablauf des Prozesses des Magmen-Aufstiegs und Abflusses gezeigt, welcher nicht mittels der normalen petrochemischen Untersuchungen ersichtlich ist.Besonders die in Betracht gezogenen Spurenelemente erlauben die Unterscheidung der magmatischen Evolution in den tiefen Lagen von den oberflächlicheren Differentiationen, welche an das vulkanische Geschehen gebunden sind.In dieser Hinsicht ist ein wichtiges Schlußergebnis die Bestätigung des Alkaliverlustes seitens der oberflächlichen Sektoren der Magmaherde, ein Verlust welcher eigenartige Deformationen von den normalen petrogenetischen Linien gezeigt hat.

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Résumé L'étude pétrographique et volcanologique des manifestations magmatiques quaternaires de la province alcalin-potassique du Latium septentrional (Volcans Sabatini, Vico et Vulsini) nous a permis de vérifier les rapports entre la différenciation magmatique, l'évolution volcanologique et la distribution de quelques éléments en traces.Dans ce but on a exécuté plusieurs centaines d'analyses de U, Th, Be, Zn, Rb, Sr, éléments qui sont présents en quantité exceptionellement élevé dans les roches alcalines examinées.L'étude de la distribution de ces éléments a permis une compréhension plus approfondie de certains types de differenciation et surtout, elle a indiqué l'existence de processus liés à la remontée et effusion des magmas, qui ne sont pas relevables par les examens pétrochimiques normaux.En particulier les éléments en traces considérés permettent de distinguer l'évolution magmatique de milieu profond des différenciations superficielles liées aux situations volcaniques.A ce propos une conclusion importante a été la constatation de la perte d'alcali par les portions plus superficielles des réservoirs magmatiques; une perte qui a déterminé des déformations particulières qui les éloignent des lignes pétrogénétiques normales.

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Authors are indepded to Dr. S.Smcana and to Dr. G.Falchi for the analyses performance.     

Little Black Holes: Dark Matter and Ball Lightning

Small, quiescent black holes can be considered as candidates for the missing dark matter of the universe, and as the core energy source of ball lightning. By means of gravitational tunneling, unidirectional radiation is emitted from black holes in a process much attenuated from that of Hawking radiation, P, which has proven elusive to detect. Gravitational tunneling emission is similar to electric field emission of electrons from a metal in that a second body is involved which lowers the barrier and gives the barrier a finite rather than infinite width. Hawking deals with a single isolated black hole. The radiated power here is P ∝ e^-2Δγ P, where e^-2Δγ is the transmission probability. This revised version was published online in August 2006 with corrections to the Cover Date.     

Levels of chlorinated hydrocarbons in marine animals from the central Mediterranean

Concentrations of chlorinated hydrocarbons (DDT and metabolites, PCBs, aldrin, dieldrin, HCB and BHCs) have been determined in the tissues of five species of marine animals sampled in selected areas of the central Mediterranean.     

Solar constant and sunspots

Summary The relationship, already found by the authors, between sunspot numbers and the solar constant, as deduced from the highest global irradiance values at noon, is here reexamined and confirmed. Some attempts at explanation and further inferences are presented.