Agglutinated foraminifera from neritic to bathyal facies in the Palaeogene of Spitsbergen and the Barents Sea

Late Palaeocene to Early Eocene foraminiferal assemblages have been analysed from an exploratory well (7119/7-1) drilled in the Tromsø Basin (southwestern Barents Sea) and from two onshore sections, Basilikaelva and Kovalskifjella, exposed in the Central Tertiary Basin of Spitsbergen. The assemblages reveal marked differences in taxonomic composition and diversity, reflecting inner neritic to middle bathyal conditions. Within this depth range, four foraminiferal biofacies (FB) are distinguished: FB 1 occurs in the Kolthoffberget Member (of the Firkanten Formation, Late Palaeocene) sampled in the Basilikaelva section. The member consists of interbedded shales, siltstones and sandstones deposited in a transitional delta front - prodelta environment, according to current sedimentological interpretation. The foraminiferal assemblages are entirely agglutinated, show extremely low species diversities and strong dominance of Reticulophragmium arcticum followed by Labrospira aff. turbida. FB 2 is recognised in the Basilika Formation (Late Palaeocene) exposed in the Kovalskifjella section. The formation consists of silty claystones deposited in a prodelta shelf setting. The foraminiferal assemblages show an increased species diversity, and consist mainly of agglutinated taxa with a strongly subordinate calcareous component. The two most abundant species are R. arcticum and L. aff. turbida. Species of Verneuilinoides and Trochammina occur in significant numbers while tubular taxa are rare. FB 3 is found in the Lower Eocene clay interval composing the upper part of the Torsk Formation in well 7119/7-1. It contains entirely agglutinated assemblages with comparatively high diversities. The dominant species are Recurvoides aff. turbinatus and Budashevaella multicamerata, while Reticulophragmium amplectens is typical and common in these strata. Tubular forms referred to Rhizammina occur locally in significant quantities. The diversity and composition of the assemblages suggest an outer neritic to upper bathyal environment. FB 4 is developed in Palaeocene claystones comprising the lower part of the Torsk Formation in well 7119/7-1. In this interval the species diversity, as well as the frequency of tubular forms (referred to Rhizammina, Bathysiphon and Hyperammina) attains maximum values. Other common to dominant taxa include Spiroplectammina spectabilis, Haplophragmoides walteri, Ammosphaeroidina pseudopauciloculata, and Recurvoides sp. These wholly agglutinated assemblages are interpreted as reflecting upper to middle bathyal conditions

Formation and transport of photooxidants over Europe during the July 2006 heat wave ? observations and GEM-AQ model simulations

International audienceThe European heat wave of July 2006 was caused by advection of very hot and dry air from North Africa. Air masses were transported on the western edge of the high pressure system, centred over Eastern Europe, resulting in exceptionally high air temperatures over large areas of the continent. In the first two weeks of July 2006 a severe heat wave affected Central and North-Eastern Europe. We present a synoptic analysis of the July 2006 European heat wave, resulting formation and transport of photooxidants over Europe as simulated by the on-line tropospheric chemistry model GEM-AQ. The model was executed on a global variable grid with ~15 km resolution over the entire European continent. Modelling results have been compared with surface observations and vertical soundings of meteorological and air quality parameters. We find that the calculated error measures, as well as analysis of time series and trends for selected quantities, indicate good model performance over the simulation period. The spatial pattern of two exposure indicators ? SOMO35 and AOT40 ? showed similarities with the high temperatures distribution. The zone of highest exposure was located over Central Europe along the advection path of the hot African air mass. The exposure to high ozone concentrations in higher latitudes was reduced by the dilution and aging of polluted air masses advected from over Central Europe

Calculations of Arctic ozone chemistry using objectively analyzed data in a 3-D CTM

A three-dimensional chemical transport model (CTM) (Kaminski, 1992) has been used to study the evolution of the Arctic ozone during the winter of 1992. The continuity equation has been solved using a spectral method with Rhomboidal 15 (R15) truncation and leap-frog time stepping. Six-hourly meteorological fields from the Canadian Meteorological Center global objective analysis routines run at T79 were degraded to the model resolution. In addition, they were interpolated to the model time grid and were used to drive the model from the surface to 10 mb. In the model, processing of Cl(x) occurred over Arctic latitudes but some of the initial products were still present by mid-January. Also, the large amounts of ClO formed in the model in early January were converted to ClNO3. The results suggest that the model resolution may be insufficient to resolve the details of the Arctic transport during this time period. In particular, the wind field does not move the ClO(x) 'cloud' to the south over Europe as seen in the MLS measurements

Pulverizações foliares de cálcio em pessegueiros cultivados na Serra Gaúcha do Rio Grande do Sul e alterações no teor de nutrientes na folha, no fruto e rendimento.

bitstream/CNPUV/9556/1/cot081.pd

Nanometer Scale Mapping of the Density of States in an Inhomogeneous Superconductor

Using high speed scanning tunneling spectroscopy, we perform a full mapping of the quasiparticle density of states (DOS) in single crystals of BiPbSrCaCuO(2212). The measurements carried out at 5 K showed a complex spatial pattern of important variations of the local DOS on the nanometer scale. Superconducting areas are co-existing with regions of a smooth and larger gap-like DOS structure. The superconducting regions are found to have a minimum size of about 3 nm. The role of Pb-introduced substitutional disorder in the observed spatial variations of the local DOS is discussed.Comment: 4 page Letter with 3 figures (2 color figures

On knottings in the physical Hilbert space of LQG as given by the EPRL model

We consider the EPRL spin foam amplitude for arbitrary embedded two-complexes. Choosing a definition of the face- and edge amplitudes which lead to spin foam amplitudes invariant under trivial subdivisions, we investigate invariance properties of the amplitude under consistent deformations, which are deformations of the embedded two-complex where faces are allowed to pass through each other in a controlled way. Using this surprising invariance, we are able to show that in the physical Hilbert space as defined by the sum over all spin foams contains no knotting classes of graphs anymore.Comment: 22 pages, 14 figure

Modelling stratospheric polar ozone using objective analysis

We have studied the development of the austral ozone hole using a 3-D spectral chemical transport model at R15 resolution for the period 15th September to 15th October, 1991. The model is driven by objectively analyzed wind fields obtained from the Canadian Meteorological Center and uses the chemical module developed by Kaminski (1992). Although extensive processing of NO(y) and Cl(x) occurs within the model, the ozone hole that develops appears shallow and ephemeral. Analysis of the results indicate that the meridional transport of ozone is sufficient to overwhelm the substantial chemical depletion that does occur. We suggest that the low resolution objectively analyzed data used is unable to capture the essential isolated nature of the vortex

Timeless path integral for relativistic quantum mechanics

Starting from the canonical formalism of relativistic (timeless) quantum mechanics, the formulation of timeless path integral is rigorously derived. The transition amplitude is reformulated as the sum, or functional integral, over all possible paths in the constraint surface specified by the (relativistic) Hamiltonian constraint, and each path contributes with a phase identical to the classical action divided by $\hbar$. The timeless path integral manifests the timeless feature as it is completely independent of the parametrization for paths. For the special case that the Hamiltonian constraint is a quadratic polynomial in momenta, the transition amplitude admits the timeless Feynman's path integral over the (relativistic) configuration space. Meanwhile, the difference between relativistic quantum mechanics and conventional nonrelativistic (with time) quantum mechanics is elaborated on in light of timeless path integral.Comment: 41 pages; more references and comments added; version to appear in CQ

Deformation of anisotropic Fermi surfaces due to electron-electron interactions

We analyze the deformations of the Fermi surface induced by electron-electron interactions in anisotropic two dimensional systems. We use perturbation theory to treat, on the same footing, the regular and singular regions of the Fermi surface. It is shown that, even for weak local coupling, the self-energy presents a nontrivial behavior showing momentum dependence and interplay with the Fermi surface shape. Our scheme gives simple analytical expressions based on local features of the Fermi surface.Comment: 7 pages, 3 figure