1,174 research outputs found
The stratigraphy, correlation, provenance and palaeogeography of the Skiddaw Group (Ordovician) in the English Lake District
A new lithostratigraphy is presented for the Skiddaw Group (lower Ordovician) of the English Lake District. Two stratigraphical belts are described. Five formations are defined in the Northern Fells Belt, ranging in age from Tremadoc to early Llanvirn. They are all mudstone or sandstone dominated, of turbidite origin; in ascending order they are named the Bitter Beck, Watch Hill, Hope Beck, Loweswater and Kirk Stile formations. Two formations are defined in the Central Fells Belt, ranging in age from late Arenig to Llanvirn. These are the Buttermere Formation - a major olistostrome deposit - overlain by the Tarn Moor Formation, consisting of turbidite mudstones with volcaniclastic turbidite sandstone beds. A revised graptolite and new acritarch biostratigraphy for the Skiddaw Group is presented with eight graptolite biozones and thirteen acritarch assemblages and sub-assemblages. The provenance of the group is assessed from detailed petrographical and geochemical work. This suggests derivation, in the early Ordovician, largely from an old inactive continental arc terrane lying to the south-east, with the appearance of juvenile volcanic material in the Llanvirn. Comparisons and correlations of the Skiddaw Group are made with the Isle of Man and eastern Ireland
Chronic pain and opioid analgesic use : a case report
Opioids are often ineffective for managing chronic non-malignant pain. If prescribed, this should be as part of an opioid trial with clear aims of therapy, tapering/stopping if it is ineffective, or if it is causing adverse effects. Clinical guidance is available but there are many gaps in the evidence
Mineral exploration in the Cockermouth area, Cumbria. Part 2: follow-up surveys
This report describes the results of geochemical, geological and geophysical surveys across three
small areas of Carboniferous and Lower Palaeozoic rocks along the northern margin of the English
Lake District. The areas were chosen from the appraisal of regional-scale survey data described by
Cooper et al. (1991). In two of the areas, Ruthwaite and Tallentire, the objective was to provide
more information on the extent and magnitude of fracture-controlled epigenetic baryte and base
metal mineralisation. In the third area, at Whitrigg, brief surveys were carried out to aid the
interpretation of unexplained geochemical and geophysical anomalies found during two projects
carried out under the Mineral Exploration and Investment Grants Act (MEIGA).
At Ruthwaite, where a mine formerly worked baryte from a fault separating Lower Palaeozoic and
Carboniferous rocks, surface indications of further baryte mineralisation were found. Soil analyses
indicated that mineralisation may be present along the continuation of the faultline worked at
Ruthwaite and in the Eycott Volcanic Group rocks to the south of it. In this area relatively small,
but in some circumstances perhaps economically attractive, deposits of baryte may be present
under drift cover.
In the Tallentire Hill area, geological mapping followed by traverse-based soil sampling showed
that fracture-controlled mineralisation is widespread in the Carboniferous (Dinantian and
Namurian) rocks. The fracture fillings consist dominantly of baryte, often accompanied by
carbonate, with traces of copper and mercury. Where seen at surface the fracture fillings are too
small, patchy and low-grade to be of any economic importance. Baryte mineralisation also occurs
locally as patchy impregnations in sandstones. These are considered to be epigenetic deposits
related to the fracture-controlled mineralisation. Trial geophysical surveys suggested that electrical
methods may be useful in determining the extent of the mineralised sandstone. There is a
possibility that more extensive baryte deposits may be present in the limestone succession
underlying the mineralised sandstones.
In the Whitrigg area, Carboniferous rocks are separated from Lower Palaeozoic rocks of the
Eycott Volcanic Group by the easterly-trending Boundary Fault and north-westerly-trending
Bothel Fault. Evidence from an old mineral working and the results of a soil survey indicate that
patchy, epigenetic, fracture-controlled baryte and base metal mineralisation occurs along the
Bothel Fault and, locally, in the adjacent rocks. A feature of this mineralisation is the presence of
mercury, which is most abundant in a sample of brecciated and altered rock from the Eycott
Volcanic Group. Prominent base metal in soil anomalies discovered by MEIGA-funded projects
near Stangerhill are not associated with barium anomalies. It was concluded that these soil
anomalies are most likely to be caused by secondary concentration in overburden, and that the
source of metals may be a sub-cropping metalliferous horizon within the Carboniferous succession
or, more probably, fracture-controlled mineralisation.
Trial geophysical surveys carried out in all three areas indicated that in ground free of artificial
sources the VLF(EM) and conductivity mapping methods could be useful for tracing faults beneath
drift and providing information on drift thickness. Closely-spaced soil sampling proved effective for
detecting mineralisation in areas where the drift cover is thin, and a trial soil-gas survey showed
that this technique could also be useful for tracing faults beneath drift
Compact boson stars in K field theories
We study a scalar field theory with a non-standard kinetic term minimally
coupled to gravity. We establish the existence of compact boson stars, that is,
static solutions with compact support of the full system with self-gravitation
taken into account. Concretely, there exist two types of solutions, namely
compact balls on the one hand, and compact shells on the other hand. The
compact balls have a naked singularity at the center. The inner boundary of the
compact shells is singular, as well, but it is, at the same time, a Killing
horizon. These singular, compact shells therefore resemble black holes.Comment: Latex, 45 pages, 25 figures, some references and comments adde
Thermodynamics of Dipolar Chain Systems
The thermodynamics of a quantum system of layers containing perpendicularly
oriented dipolar molecules is studied within an oscillator approximation for
both bosonic and fermionic species. The system is assumed to be built from
chains with one molecule in each layer. We consider the effects of the
intralayer repulsion and quantum statistical requirements in systems with more
than one chain. Specifically, we consider the case of two chains and solve the
problem analytically within the harmonic Hamiltonian approach which is accurate
for large dipole moments. The case of three chains is calculated numerically.
Our findings indicate that thermodynamic observables, such as the heat
capacity, can be used to probe the signatures of the intralayer interaction
between chains. This should be relevant for near future experiments on polar
molecules with strong dipole moments.Comment: 15 pages, 5 figures, final versio
Parental stressors in professional youth football academies: a qualitative investigation of specialising stage parents
Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV
We report the results of a study of color coherence effects in ppbar
collisions based on data collected by the D0 detector during the 1994-1995 run
of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8
TeV. Initial-to-final state color interference effects are studied by examining
particle distribution patterns in events with a W boson and at least one jet.
The data are compared to Monte Carlo simulations with different color coherence
implementations and to an analytic modified-leading-logarithm perturbative
calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters
Microbiological profile of donor corneas stored for tectonic transplantation purposes in rabbits
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
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