1,047 research outputs found
The Jurassic Source Rock Potential of the Celtic Sea and Western Approaches
A working petroleum system requires the presence of mature source rocks that have generated significant quantities of petroleum along with favourable timing of generation and expulsion with respect to the reservoir, trap and seal development. The Oil and Gas Authority (OGA) is currently promoting exploration in frontier basins extensional Mesozoic half graben and graben basins of the Western Approaches and Celtic Sea regions. Despite initial exploration efforts during the 1970s to 1990s, the source rock potential and likely timing of hydrocarbon generation and expulsion in the Celtic Sea and Western Approaches remain poorly understood. The Dragon Discovery, located between the North Celtic Sea and St Georgeâs Channel Basins is the only discovery (gas with minor oil shows). Analysis of legacy geochemical datasets suggests that the Jurassic mudrocks contain the main intervals of potential source rock.
The Lower Jurassic strata in the Western Approaches and Celtic Sea Basins are shown to have highly variable source rock potential. Regionally, Sinemurian to Pliensbachian mudrocks form a zone of correlatable source rock potential with Total Organic Carbon commonly greater than 2% and Hydrogen Index values of greater than 200 mg/g. The main limiting factors are the general immaturity to early maturity of Jurassic strata, and the limited preservation of Jurassic sediments, especially in the Western Approaches. Late Jurassic to Early Cretaceous uplift and erosion caused the truncation of Jurassic strata in the Western Approaches and South Celtic Sea Basin, and a cessation in the increase of the thermal maturity of the Jurassic interval. This Late Jurassic to Early Cretaceous uplift and erosion event is suggested as the main control on the preservation and maturity (0.4-0.6% Ro) of Jurassic source rocks in the UK sector of the Celtic Sea and Western Approaches. The potential also exists for the preservation of more deeply buried sections of Jurassic source rock in localised graben at greater thermal maturity (>0.55% Ro)
Faults, fractures and fluids in mudstones during Cenozoic extension in the Cleveland Basin
Fractures and faults may act as important fluid-flow pathways through low permeability mudstone sequences; understanding their occurrence and properties is thus important when considering the risks of leakage of petroleum from underlying reservoirs, or CO2 from storage sites. Fluid-flow is also an important in radioactive waste storage sites during construction or operation of the sites. This project studies calcite-filled fractures and faults developed within the exhumed, early-mature, Jurassic mudstone succession of the Cleveland Basin, NE England, combining structural geology with isotope geochemistry and geochronology. The abundance of well-exposed, natural fractures with different orientations and failure modes provides an opportunity to investigate the properties of these fractures and provides a basin-wide temporal and spatial framework of evolving deformation.
Calcite veins and fault fills are present in N-S to NNW-SSE trending normal faults and associated fractures in the north of the Cleveland Basin. U-Pb calcite geochronology has yielded ages in the range 45-20Ma for sampled calcite. This describes a previously unrecognised phase of Cenozoic faulting. I propose that this deformation relates salt-related deformation following regional tilting, uplift and eastwards gravity sliding related to Atlantic opening and the development of the proto-Icelandic plume to the NW of Britain.
Structural and petrographic observations suggest that N-S trending faults have complex kinematic and fluid-flow histories. Faults are characterised by damage zones with widespread calcite mineralisation, extensional jog structures and fracture reactivation. Stable isotope and clumped isotope analyses suggest that the regional fracture-controlled fluid-flow during the Cenozoic deformation involved post-exhumation mixing of cool meteoric waters (20°C) with warmer (80°C) basinal fluids. I hypothesise that fluid is driven by gravity-driven regional extension. Whilst fault-related displacements are modest, meaning that the structures are unlikely to be widely resolved in offshore seismic reflection profiles, they are widespread and therefore are inferred to represent highly effective fluid-flow pathways. Our findings place new important constraints on the poorly constrained Cenozoic tectonic history of the Cleveland Basin and northeast Britain
Dublin City University video track experiments for TREC 2001
Dublin City University participated in the interactive search task and Shot Boundary Detection task* of the TREC Video Track. In the interactive search task experiment thirty people used three different digital video browsers to find video segments matching the given topics. Each user was under a time constraint of six minutes for each topic assigned to them. The purpose of this experiment was to compare video browsers and so a method was developed for combining independent usersâ results for a topic into one set of results. Collated results based on thirty users are available herein though individual usersâ and browsersâ results are currently unavailable for comparison. Our purpose in participating in this TREC track was to create the ground truth within the TREC framework, which will allow us to do direct browser performance comparisons
Entropy and energy conservation for thermal atmospheric dynamics using mixed compatible finite elements
Atmospheric systems incorporating thermal dynamics must be stable with
respect to both energy and entropy. While energy conservation can be enforced
via the preservation of the skew-symmetric structure of the Hamiltonian form of
the equations of motion, entropy conservation is typically derived as an
additional invariant of the Hamiltonian system, and satisfied via the exact
preservation of the chain rule. This is particularly challenging since the
function spaces used to represent the thermodynamic variables in compatible
finite element discretisations are typically discontinuous at element
boundaries. In the present work we negate this problem by constructing our
equations of motion via weighted averages of skew-symmetric formulations using
both flux form and material form advection of thermodynamic variables, which
allow for the necessary cancellations required to conserve entropy without the
chain rule. We show that such formulations allow for stable simulations of both
the thermal shallow water and 3D compressible Euler equations on the sphere
using mixed compatible finite elements without entropy damping
Focussed palmtop information access combining starfield displays and profile-based recommendations
This paper presents two palmtop applications: Taeneb CityGuide and Taeneb ConferenceGuide. Both applications are centred around Starfield displays on palmtop computers - this provides fast, dynamic access to information on a small platform. The paper describes the applications focussing on this novel palmtop information access method and on the user-profiling aspect of the CityGuide, where restaurants are recommended to users based on both the match of restaurant type to the users' observed previous interactions and the rating given by reviewers with similar observed preferences
Model System for the Production of Enzyme Modified Cheese (EMC) Flavours.
End of Project ReportNatural cheese flavour ingredients, in the form of enzyme modified
cheeses (EMCs), are widely used in the convenience food industry
and can provide high volume added opportunities for the cheese
industry.
Many EMCs are produced using commercial enzyme preparations
and previous studies have indicated that they contain side activities in
addition to their stated main activity (see DPRC Report No.10).
Therefore, it is critical that the exact enzyme complement of these
preparations are known before they can be used to produce EMC of
specific requirements on a consistent basis.
The scientific basis of rapid enzyme mediated flavour formation in the
production of EMCs is not fully understood. Consequently this
knowledge gap is a major obstacle in the development of high value
cheese flavour ingredients.
Hence, a major objective of this project was to deepen the scientific
understanding of flavour formation with a view to the production of
natural enzyme-mediated dairy flavour ingredients with commercial
potential.
The ultimate aim was to develop the technology to produce
customised high value dairy flavour ingredients in an optimised
process.Dairy LevyDepartment of Agriculture, Food and the Marin
Digital manipulation of faces and its consequence upon identification and attractiveness
The thesis investigated perception of facial identity and attractiveness with digital manipulation of facial traits. A presentation time paradigm was developed by which stimuli could be presented for a range of brief display periods. Using this paradigm subjects recognised photo-realistic target faces caricatured in shape with greater accuracy than veridical images consistent with previous findings using reaction time as a measure. Subjects were further required to identify colour representations of famous faces which were either veridical, caricatured in colour space or had enhanced colour saturation and intensity contrast (as contrast controls). Recognition accuracy was greater when viewing the colour-caricatured stimuli than either the veridical images or the contrast controls. The removal of colour to produce grey-scale images also decreased accuracy of face recognition indicating that colour information aids facial identification. Caricaturing of faces, therefore, can be extended to the colour domain and, as with shape caricaturing, enhancement of distinctive information can produce a recognition advantage for famous faces. Subjects were also asked to identify the best-likeness for individuals using photo-realistic stimuli and an interactive paradigm with shape-caricature, colour-caricature and contrast-control varied by the user in real-time. The best-likeness with shape manipulation was a slight anti-caricature while with colour-caricature and contrast-control images a mildly exaggerated image was selected as the best-likeness. Thus although images caricatured substantially in colour or shape (+40%) induce superior recognition compared to veridical images such substantial exaggerations are not seen as best-likenesses under prolonged exposure. The gender typicality for white British and Japanese composite faces was manipulated and subjects presented with the images using both a static forced-choice paradigm and an interactive paradigm. Male and female face shapes with enhanced feminine features were consistently found to be more attractive than average. Preference for enhanced femininity for female faces was greater for subjects making within- than cross-cultural judgements
The FĂschlĂĄr-News-Stories system: personalised access to an archive of TV news
The âFĂschlĂĄrâ systems are a family of tools for capturing, analysis, indexing, browsing, searching and summarisation of digital video information. FĂschlĂĄr-News-Stories, described in this paper, is one of those systems, and provides access to a growing archive of broadcast TV news. FĂschlĂĄr-News-Stories has several notable features including the fact that it automatically records TV news and segments a broadcast news program into stories, eliminating advertisements and credits at the start/end of the broadcast. FĂschlĂĄr-News-Stories supports access to individual stories via calendar lookup, text search through closed captions, automatically-generated links between related stories, and personalised access using a personalisation and recommender system based on collaborative filtering. Access to individual news stories is supported either by browsing keyframes with synchronised closed captions, or by playback of the recorded video. One strength of the FĂschlĂĄr-News-Stories system is that it is actually used, in practice, daily, to access news. Several aspects of the FĂschlĂĄr systems have been published before, bit in this paper we give a summary of the FĂschlĂĄr-News-Stories system in operation by following a scenario in which it is used and also outlining how the underlying system realises the functions it offers
Polarization transitions in interacting ring 1D arrays
Periodic nanostructures can display the dynamics of arrays of atoms while
enabling the tuning of interactions in ways not normally possible in Nature. We
examine one dimensional arrays of a ``synthetic atom,'' a one dimensional ring
with a nearest neighbor Coulomb interaction. We consider the classical limit
first, finding that the singly charged rings possess antiferroelectric order at
low temperatures when the charge is discrete, but that they do not order when
the charge is treated as a continuous classical fluid. In the quantum limit
Monte Carlo simulation suggests that the system undergoes a quantum phase
transition as the interaction strength is increased. This is supported by
mapping the system to the 1D transverse field Ising model. Finally we examine
the effect of magnetic fields. We find that a magnetic field can alter the
electrostatic phase transition producing a ferroelectric groundstate, solely
through its effect of shifting the eigenenergies of the quantum problem.Comment: 12 pages in two column format, 18 figure
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