bluuebunny/crossref_metadata_2025 huggingface dataset:
DISCRIMINATIVE TRAINING BASED QUADRATIC CLASSIFIER FOR HANDWRITTEN CHARACTER RECOGNITION
Authors: ZHANG RUI , DING XIAO QING , LIU HAI LONG
Published: September 2007

In offline handwritten character recognition, the classifier with modified quadratic discriminant function (MQDF) has achieved good performance. The parameters of MQDF classifier are commonly estimated by the maximum likelihood (ML) estimator, which maximizes the within-class likelihood instead of directly minimizing the classification errors. To improve the performance of MQDF classifier, in this paper, the MQDF parameters are revised by discriminative training using a minimum classification error (MCE) criterion. The proposed algorithm is applied to recognizing handwritten numerals and handwritten Chinese characters, the recognition rates obtained are among the highest that have ever been reported.
PERFORMANCE ANALYSIS OF FACE RECOGNITION ALGORITHMS ON KOREAN FACE DATABASE
Authors: ROH MYUNG-CHEOL , LEE SEONG-WHAN
Published: September 2007

Human face is one of the most common and useful keys to a person's identity. Although, a number of face recognition algorithms have been proposed, many researchers believe that the technology should be improved further in order to overcome the instability caused by variable illuminations, expressions, poses and accessories. To analyze these face recognition algorithm, it is indispensable to collect various data as much as possible. Face databases such as CMU PIE (USA), FERET (USA), AR Face DB (USA) and XM2VTS (UK) are the representative ones commonly used. However, many databases do not provide adequately annotated information of the pose angle, illumination angle, illumination color and ground-truth. Mostly, they do not include large enough number of images and video data taken under various environments. Furthermore, the faces on these databases have different characteristics from those of Asian. Thus, we have designed and constructed a Korean Face Database (KFDB) which includes not only images but also video clips, ground-truth information of facial feature points and descriptions of subjects and environment conditions so that it can be used for general purposes. In this paper, we present the KFDB which contains image and video data for 1920 subjects and has been constructed in 3 years (sessions). We also present recognition results by CM (Correlation Matching) and PCA (Principal Component Analysis) which are used as baseline algorithms upon CMU PIE and KFDB, so as to understand how recognition rate is changed by altering image taking conditions.
FIVE NEW FEATURE SELECTION METRICS IN TEXT CATEGORIZATION
Authors: SONG FENGXI , ZHANG DAVID , XU YONG , WANG JIZHONG
Published: September 2007

Feature selection has been extensively applied in statistical pattern recognition as a mechanism for cleaning up the set of features that are used to represent data and as a way of improving the performance of classifiers. Four schemes commonly used for feature selection are Exponential Searches, Stochastic Searches, Sequential Searches, and Best Individual Features. The most popular scheme used in text categorization is Best Individual Features as the extremely high dimensionality of text feature spaces render the other three feature selection schemes time prohibitive.

This paper proposes five new metrics for selecting Best Individual Features for use in text categorization. Their effectiveness have been empirically tested on two well- known data collections, Reuters-21578 and 20 Newsgroups. Experimental results show that the performance of two of the five new metrics, Bayesian Rule and F-one Value, is not significantly below that of a good traditional text categorization selection metric, Document Frequency. The performance of another two of these five new metrics, Low Loss Dimensionality Reduction and Relative Frequency Difference, is equal to or better than that of conventional good feature selection metrics such as Mutual Information and Chi-square Statistic.
ARTISTIC BOX TREES
Authors: BROWNE CAMERON
Published: September 2007

This short note describes a development of the traditional Pythagorean tree fractal that produces three-dimensional structures based on cubes rather than squares. Adding a 90° rotation at each bifurcation encourages three-dimensional growth, creating increasingly artistic shapes as the branching angle decreases.
DIMENSIONS OF SELF-AFFINE FRACTALS AND MULTIFRACTALS GENERATED BY UPPER-TRIANGULAR MATRICES
Authors: FALCONER KENNETH , MIAO JUN
Published: September 2007

We consider calculation of the dimensions of self-affine fractals and multifractals that are the attractors of iterated function systems specified in terms of upper-triangular matrices. Using methods from linear algebra, we obtain explicit formulae for the dimensions that are valid in many cases.
A FRACTAL MODEL FOR RELATIVE PERMEABILITY OF UNSATURATED POROUS MEDIA WITH CAPILLARY PRESSURE EFFECT
Authors: LIU YANJUN , YU BOMING
Published: September 2007

A fractal relative permeability model is derived which takes into account the capillary pressure difference effect. The proposed model is expressed as a function of saturation, fractal dimensions, fluid properties and capillary pressure difference, and there is no empirical constant introduced in the proposed model. The effect of the capillary pressure difference on the relative permeability is analyzed, and the results indicate that the capillary pressure difference has the significant influence on the relative permeability at low saturation. The predicted relative permeabilities are compared with the available experimental data. Good agreement is found between the present model predictions and the available experimental data.
Biotechnology Industry in Australia: Growing Fast
Authors: Coulepis Anthony
Published: September 2007

The article discusses about the fast fact on Australia's biotechnology industry and its key industry sectors. It also contains the major stakeholders of the big players in biotechnology sector. Also, it touches on the regulatory bodies and the intellectual property laws in Australia.
New Zealand Biotechnology Overview
Authors: Ross Christine , Ward Brian
Published: September 2007

This article talks about New Zealand's biotechnology strengths, general trends and opportunities in New Zealand. It touches on nutrigenomics, nutraceuticals, biomedical, agricultural, clinicalt rials, bio-prospecting, bio-secuitry and NZBio.
Strategies for Converting Intellectual Property Into Profit
Authors: Golias Helen
Published: September 2007

The article touches on the intellectual property rights and protecting licensing issues.
Documenting in Biotechnology
Authors: Agricola Sebastian , Muralitharan Morley
Published: September 2007

The article is about documenting in Biotechnology. It touches on enterprise ventures between partners and corporate joint ventures.
Merger-Driven Vertical Integration to Create a Global Biopharmaceutical Company
Authors: Campbell James A.
Published: September 2007

The article is about the Australian company, Chemgenex Pharmaceuticals. It touches on the focus of the company and its capabilities and technologies.
Singapore – The Biopolis of Asia
Authors: Beh Swan Gin
Published: September 2007

The article touches on the trend of the biotechnology market in Singapore. It discusses about the growing base of drug discovery and development activities. It also states the new bio-enterprises and the world class scientists that Singapore has attracted.
Commentaries & Analyses — Snapshot of Current Australian Biotechnology Boom Indicators
Authors: Muralitharan Morley , Agricola Sebastian , Coulepis Tony , Chandler Steve , Gray Chris
Published: September 2007

No abstract reveived.
The Development of Heparin-Like Sugars as Stem Cell-Active Drugs: A Uniquely Singapore Slant on an Old Problem
Authors: Cool Simon M. , Nurcombe Victor
Published: September 2007

The article is about the research on the development of heparin-like sugars as stem cell-active drugs.
BIOPOLIS SHARED FACILITIES: EXPANDING THE CORE OF DISCOVERY THROUGH SHARED FACILITIES
Authors: Ren Ee Chee
Published: September 2007

The article is about Biopolis Shared Facilities. It is an overview of the purpose-built resource that provides research support to the Biopolis community. It mentions the facilities, equipment and technologies that it offers to the Biopolis community.
Singapore — The Biopolis of Asia
Authors: Beh Swan Gin
Published: September 2007

The article is about how Singapore is building up capabilities in the Biomedical Sciences. BMRC, BMSG and Bio*One are to implement Singapore's biomedical sciences. The article discusses the approach taken by the three agencies to promote the industry by focussing on the developmental of industrial capital, intellectual capital and human capital.
Petroleum systems offshore western Ireland in an Atlantic margin context
Authors: Spencer A. M. , MacTiernan B.
Published: September 2007

The Rockall, Slyne, Erris and Porcupine basins on the Atlantic margin off Ireland belong to a family of geologically similar basins stretching from offshore mid-Norway to offshore Newfoundland. Jurassic sequences act as reservoir and source rocks in many of the basins. Cretaceous extensional faulting was widespread and major subsidence affected several basins. Cretaceous submarine fan and shallow marine sandstones and Paleocene submarine fan sandstones often provide reservoir targets. Cretaceous and Paleocene to Eocene volcanic rocks are widespread and Eocene to Recent net subsidence has resulted in water depths which generally exceed 200m and reach over 2000m in the south. Passive uplift affected the land areas to the east in Neogene times.

Proven Jurassic-sourced petroleum systems occur in six basins from the Halten Terrace to the Jeanne d’Arc Basin, including the northern Porcupine Basin and the Slyne-Erris basins. In the latter the Jurassic petroleum system has been destroyed by uplift, but a Carboniferous petroleum system has proved successful there for gas. West and northwest of these proven basins, on the ‘outboard’ side of the Atlantic margin, are large frontier areas. Recent gas discoveries in the deep Vøring Basin prove the existence of petroleum systems there but the source is not known. On both margins of the Rockall Basin and in the southern Porcupine Basin petroleum systems may exist but are not yet proven.
Hot fluid flow events in Atlantic margin basins: an example from the Rathlin Basin
Authors: Middleton David W. J. , Parnell John , Green Paul F. , Xu Guojian , McSherry Marie
Published: September 2007

An understanding of the thermal and tectonic evolution of sedimentary basins is essential to the effective modelling of source rock maturation and hydrocarbon charge and entrapment histories of potential hydrocarbon systems. A growing body of data suggests that a number of basins on the Atlantic margin to the west of Britain and Ireland have suffered short-lived episodes of migration of anomalously hot fluids through reservoir intervals. These events leave higher temperature signatures in affected basins than predicted from burial under conditions of vertical conductive heat transfer, and should be considered during hydrocarbon appraisal of a prospective basin. The Rathlin Basin displays a thermal history influenced by one or more such hot fluid flow events, with fluid palaeotemperatures in excess of 170°C recorded in the Permo-Triassic and Carboniferous section, and is typical of other Atlantic margin basins affected in this way.
Hydrocarbon prospectivity in the Irish Sea area: insights from recent exploration of the Central Irish Sea, Peel and Solway basins
Authors: Floodpage Jonathan , Newman Phil , White Jason
Published: September 2007

Compared with the prolific success of the Triassic play in the East Irish Sea Basin (EISB) the lack of hydrocarbon discovery in neighbouring Permo-Triassic basins of the Irish Sea has been an enigma. However, recent exploration of the Peel, Solway and Central Irish Sea basins has provided new insights into the geology of these basins and the controls upon hydrocarbon prospectivity in the Irish Sea area. Regional seismic interpretation suggests that 12 of the 15 exploration wells drilled in the basins adjacent to the EISB tested valid structural closures at top Triassic reservoir level. Re-evaluation of the Irish Sea petroleum system reveals that, although effective reservoirs occur in the Lower-Middle Triassic Ormskirk Sandstone Formation, and evaporites in the Middle-Upper Triassic Mercia Mudstone Group provide a regional top seal, the major factor controlling hydrocarbon prospectivity is the limited presence of effective source rocks in the underlying Carboniferous section. A further control upon prospectivity is the timing of hydrocarbon migration, from those areas where Carboniferous source rocks were deposited and preserved. The Namurian basinal marine oil- and gas-prone shales, which form the principal source of hydrocarbons for the Triassic play in the EISB, are restricted to an east-west fairway extending from the EISB into the Kish Bank Basin. Rocks of this age are absent from the Peel and Solway basins as a result of Variscan uplift and erosion. However, palaeogeographical reconstructions based on well and outcrop data suggest that, even if preserved, the depositional environment was not conductive to the formation of marine oil-and gas-prone source rocks. Well and seismic data suggest that rocks of Namurian age were not deposited in the Central Irish Sea area, which remained high during much of Dinantian and Namurian time. Potential source rock development in the Central Irish Sea area is therefore limited to the Westphalian section, which is organically lean and dominated by intertinitic kerogens. Potential hydrocarbon traps in the Central Irish Sea, Peel and Solway basins formed largely as a result of Early Cretaceous tectonism and were subsequently modified by fault reactivation during Tertiary uplift phases. Trap formation appears to postdate the most likely timing of hydrocarbon charge, which this study suggests would have occurred in Late Triassic and Jurassic time. Hydrocarbon entrapment in the EISB may have been favoured by limited Early Cretaceous uplift, coupled with renewed hydrocarbon generation and re-migration during Early Tertiary time. It is concluded that the remaining prospectivity of the Triassic play in the Irish Sea area is likely to be restricted to the proven play fairway within the EISB.
Fault distribution and timing in the Central Irish Sea Basin
Authors: Izatt Chris , Maingarm Suvimol , Racey Andrew
Published: September 2007

Well data analysis and the interpretation of 2D and 3D seismic reflection data provide valuable insights into the distribution and timing of fault activity within the Central Irish Sea Basin (CISB). Structural and stratigraphic relationships have been used to constrain the timing of fault movements and to interpret the mapped fault patterns in terms of the tectonic evolution of the area. Four main fault trends are identified at the Top Lower Triassic Sherwood Sandstone Group level: I, a NE-SW fault trend that parallels the basin-bounding faults and is believed to be of Mesozoic age; II, a pervasive system of northsouth-trending faults that cross-cut the earlier NE-SW-trending faults, which manifests evidence of later Mesozoic extension followed by post-Oligocene transpressional fault reactivation; III, a NNE-SSW-trending, steeply dipping, fault set; IV, a WNW-ESE-trending conjugate extensional set that formed perpendicular to the NNE-SSW-trending transpressional faults during Late Tertiary dextral shearing. Early Tertiary axial centred basin inversion and regional exhumation have resulted in the elevation of the Sherwood Sandstone reservoir to shallow structural levels within the basin. Continued fault reactivation into Late Tertiary time has resulted in the compartmentalization of mapped structural closures and suggests that trap integrity is a major exploration risk factor in the CISB.
The influence of thermal history on hydrocarbon prospectivity in the Central Irish Sea Basin
Authors: Green Paul F. , Duddy Ian R. , Bray Richard J. , Duncan William I. , Corcoran Dermot V.
Published: September 2007

Thermal history reconstruction studies of four hydrocarbon exploration wells located in the Central Irish Sea Basin (CISB) reveal three major regional episodes of heating and cooling. Units throughout the pre-Quaternary section intersected in wells 42/12-1, 42/16-1 and 42/17-1 began to cool from their maximum post-depositional palaeotemperatures in Early Cretaceous time, between 120 and 115 Ma. Cooling from subsequent palaeotemperature peaks began in Late Cretaceous-Early Tertiary (70–55 Ma) and Late Tertiary (25–0 Ma) time. Results from well 42/21-1 are dominated by the two more recent episodes, and show no evidence of the Early Cretaceous episode. This is thought to reflect a different structural setting of this well, within a North Celtic Sea-Cardigan Bay trend. Palaeotemperature profiles suggest that heating in each episode was due largely to deeper burial, with subsequent cooling caused mainly by uplift and erosion. A maximum of
c.
3 km of additional Late Triassic to Early Cretaceous section is required to explain the observed Early Cretaceous palaeotemperatures. Appropriate values for the Late Cretaceous-Early Tertiary and Late Tertiary episoders are
c.
2 km and
c.
1 km, respectively. All of these cooling episodes correlate closely with similar episodes recognized from previous studies in surrounding regions, from onshore Ireland, Scotland, South Wales and northern, eastern, central and SW England, and each appears to be of truly regional extent. Exploration risk in the CISB generation can be significantly reduced through recognition of the major palaeothermal episodes that have affected the region, and the variation in the magnitude of their effects across the region. The challenge for future exploration in the region is to identify regions where the main phase of hydrocarbon generation post-dated structuring.
Late Tertiary faulting, footwall uplift and topography in western Ireland
Authors: Badley Michael E.
Published: September 2007

The Erriff Fault in south Mayo, Ireland, is a rare example within the British Isles and Ireland of a sizeable onshore fault (normal displacement >500 m) at which a correlatable stratigraphic horizon is preserved in both the footwall and the hanging wall. That this displacement probably accumulated during Late Tertiary time makes the Erriff Fault (and other similar faults in the area) all the more interesting. Structural forward modelling indicates that footwall uplift and hanging-wall subsidence accompanying faulting, followed by further isostatic uplift following glacial erosion during the Pleistocene glaciations, exercised a fundamental control on the overall form of present-day topography in western Ireland.
Sub-basalt imaging using converted waves: numerical modelling
Authors: Martini F. , Lafond C. , Kaculini S. , Bean C. J.
Published: September 2007

Both ray-tracing and frequency-wavenumber integration modelling have been used to investigate the behaviour of P waves and P to S converted waves in simple geological models, which involve a basaltic layer above a lower-velocity layer of sediments. Model parameters were adjusted to study the behaviour of these waves, under conditions of changing water depth, basalt layer thickness and a number of permutations with respect to basalt-sediment stratification. Synthetic shot gathers were generated and then analysed and processed as real data. The general approach was to document changes in reflection curves with offset, changes in the stacking velocity, variations in the imaging of deeper reflectors under different model scenarios and to understand which offsets are useful for converted wave processing. Although this work is preliminary, some general principles have been identified, which may be of use in an operational context. For example, the modelling indicates that S waves have larger amplitudes than P waves at long offsets and that P to S converted waves arrive before the sea bottom arrival at the far offset. Consequently, the recording and identification of converted waves is favoured by long offset (
c.
10 km) acquisition arrays. However, the modelling also indicates that the presence of sediment-basalt interlayering makes the identification of converted waves more difficult.
The Mesozoic evolution of the southern North Atlantic region and its relationship to basin development in the south Porcupine Basin, offshore Ireland
Authors: Johnston Sarah , Doré Anthony G. , Spencer Anthony M.
Published: September 2007

The Mesozoic history of a number of Atlantic borderland sedimentary basins can be related to the early opening history of the southern North Atlantic Ocean. Regional tectonic controls such as plate motion vectors and the pre-existing tectonic grain had an important role in basin development and are expressed as local tectonostratigraphic events. The evolving palaeogeographies for the region are demonstrated in a series of maps based on computer-generated plate reconstructions. The Porcupine Basin, centrally located in the study area, lay close to the intersection of three plate boundaries that separated Eurasia from North America and controlled opening of the Bay of Biscay. The south Porcupine Basin, where there is relatively poor data control, is considered in the context of broader platetectonic controls, which were also responsible for the development of contiguous and better understood basins during Mesozoic time. This approach provides new insight into the structural evolution and likely facies development in the south Porcupine Basin, allowing broad inferences for petroleum prospectivity to be made. Initial Permo-Triassic fault-controlled extension led to continental deposition, which, if associated with aeolian and/or fluvial reservoir rocks, will mostly be too deep to be prospective. Thermal subsidence during Early Jurassic time was associated with flooding and fine-grained clastic deposition with anticipated moderate source rock potential. Regional uplift of the northern Porcupine area during Mid-Jurassic time forced shorelines and shelves southwards and the south Porcupine Basin could contain good reservoir quality sandstones and possible waxy deltaic-type source rocks of this age. In Late Jurassic time, major crustal extension took place with potential for reservoir and source rocks in locally expanded footwall successions. Further extensional faulting occurred in earliest Cretaceous (Neocomian) time with further synrift plays possible at this level. Growth of the Porcupine Median Volcanic Ridge is attributed to Barremian-Aptian time and related to continuing extension associated with a northwesterly arm of a triple junction positioned to the south of the Porcupine area. Strong subsidence of the basin centre during this time will have a significant impact on source rock maturation and flank trap geometries in the south Porcupine Basin.
Aspects of the structure of the Porcupine and Porcupine Seabight basins as revealed from gravity modelling of regional seismic transects
Authors: Johnson H. , Ritchie J. D. , Gatliff R. W. , Williamson J. P. , Cavill J. , Bulat J.
Published: September 2007

The Porcupine Basin is characterized by a large central free air gravity anomaly high (+ 55 mGal) flanked by local lows. In contrast, the Procupine Seabight Basin has low-amplitude anomalies in its centre, flanked by edge anomalies. Two transects, one in each of these basins, have been modelled using satellite gravity data; the upper parts of the transects are constrained by interpretation of recent commercial seismic reflection data and two wells. Results from the modelling suggest that the Porcupine Basin is not in isostatic equilibrium. In contrast, the essentially zero free air anomaly over the centre of the Porcupine Seabight Basin suggests that this basin is isostatically compensated. The difference in isostatic compensation between the two basins may reflect a fundamental contrast between the strength of the crust; the crust underlying the Porcupine Basin possesses the greater strength. The Clare Lineament may represent a fundamental boundary within the ‘Avalonian Terrane’ that juxtaposes basement blocks of differing rheologies.
Reservoir characteristics of the Upper Jurassic sequence in the 35/8-2 discovery, Porcupine Basin
Authors: Robinson A. J. , Canham A. C.
Published: September 2007

The 35/8-2 well, drilled by Phillips Petroleum in 1981, tested oil and gas from a Late Jurassic reservoir within a plunging, tilted fault block. The reservoir is overpressured by 5000 psi and, despite having good porosity and high net to gross ratio, exhibits very low permeability. Three hydrocarbon-bearing sandstone intervals were encountered in the well, and more than 120 m of core was taken from these reservoir sections. The sedimentological structures identified in core are clearly indicative of a deep-water (below storm wave base) submarine fan system, comprising a wide spectrum of turbidite and debris-flow, channel and lobe deposits. Detailed petrographic analysis of the reservoir was undertaken to identify the key factors affecting reservoir quality. The sandstones are chemically immature lithic arenites, containing abundant quartz, feldspar and rock fragments. Reservoir quality is generally poor, largely as a result of the chemical instability of the sandstones. Diagenetic overprinting is the main agent of downgrading the sandstones, with kaolinites and carbonate cements blocking pore throats and reducing permeability. Facies type, sand to mud ratio and ultimately the clastic provenance of the sandstones are also critical factors affecting the reservoir quality in these sandstones. Hydrocarbon flow was predominantly from a single sandstone facies (B1) and was confined to the ‘A’ sand interval in well 35/8-2, but it is inferred that this facies may occur away from the wellbore in all three sand intervals. Uncertainties in the results of the drillstem test and pressure data demonstrate that it is not possible to confirm whether the hydrocarbons present in the reservoir are gas condensate or volatile oil. Uncertainty in the extent of the productive reservoir facies, hydrocarbon columns and hydrocarbon type are challenges that must be overcome before the reserves contained within the 35/8-2 structure can be developed.
Comparative Tertiary stratigraphic evolution of the Porcupine and Rockall basins
Authors: McDonnell A. , Shannon P. M.
Published: September 2007

The Tertiary development of the Porcupine and Rockall basins is compared in terms of stratigraphy and sedimentation. Four main unconformities are correlated between the basins and these are interpreted as being of Paleocene (C40), latest Eocene-Early Oligocene (C30), latest Early Miocene (C20) and Early Pliocene (C10) age. Seismic stratigraphic analysis of both basins suggests a greater similarity in post-Eocene deposition than in the Paleocene to Eocene stratigraphy. During Early Tertiary time a regressive succession, punctuated by minor transgressions, marks a major interruption in the general post-rift thermal subsidence pattern of the region. This regression, possibly triggered by lithospheric thermal effects and/or ridge-push stresses, resulted in deltaic and submarine fan deposition in the Porcupine Basin, with submarine channel trends indicating that sediment was sourced mainly from the Porcupine High to the north and west. Sand deposition in the Porcupine Basin occurred principally during Mid- to Late Eocene times. In contrast, Early Eocene sand input is postulated in the Rockall Basin, whereas deposition during the Mid- to Late Eocene times was more mud-prone. In Oligocene and Mio-Pliocene times, sediment build-ups, interpreted as contourites, developed towards the margins of both basins, with sedimentation principally influenced by oceanographic circulation patterns at this time. During Neogene to Recent times limited marginal sediment influx occurred in the Porcupine Basin whereas sediment input continued locally, during Neogene time, in the Hebrides region of the Rockall Basin.
Evidence of shallow gas above the Connemara oil accumulation, Block 26/28, Porcupine Basin
Authors: Games K. P.
Published: September 2007

The results of a site survey investigation, carried out in Block 26/28 of the Porcupine Basin, suggest the presence of shallow gas above the Connemara oil accumulation. The evidence for shallow gas at or close to the sea bed consists of a series of features interpreted as gas or fluid escape structures. The presence of gas at depth is suggested by two different features: an anomalously high-amplitude seismic reflector, interpreted as a gas-charged sand layer, and some isolated, seismically disturbed zones, which are identified as gas chimneys on both high-resolution 2D seismic and conventional 3D seismic data.
Thermally driven porosity reduction: impact on basin subsidence
Authors: Bjørkum P. A. , Walderhaug O. , Nadeau P. H.
Published: September 2007

At temperatures higher than
c.
80°C, thermally driven, isochemical diagenetic porosity loss in siliciclastic sediments leads to a thinning of the sediment column. This process, termed thermochemical compaction, results in surface subsidence and generation of sediment accommodation space. The diagenetic reactions driving thermochemical compaction will operate regardless of the initial mechanism of basin formation and in addition to any externally controlled processes causing continued subsidence. Thermochemical subsidence rates are an inverse function of geothermal gradients. The total rates of subsidence at the surface, including isostatic and mechanical compaction effects, may reach several tens of metres per million years, and may have been important in driving Tertiary subsidence in basins west of Ireland. Unlike the exponentially decaying subsidence caused by tectonic thinning and rifting of the crust, thermochemical basin subsidence is a self-regulated intrabasinal process, which proceeds at a relatively high constant rate over geological time. If not arrested by extrabasinal or tectonic events, the overall effect can ultimately result in sediment metamorphism and granitization.
Slope instability and sediment redistribution in the Rockall Trough: constraints from GLORIA
Authors: Unnithan V. , Shannon P. M. , McGrane K. , Readman P. W. , Jacob A. W. B. , Keary R. , Kenyon N. H.
Published: September 2007

A recent GLORIA (Geological LOng Range Inclined Asdic) sidescan survey covered 200 000 km2of the sea bed in the Irish Rockall Trough. It revealed a range of sedimentary features on the trough floor and its steep (>6°) margins. The western margin is characterized by large-scale (of the order of hundreds of kilometres in length) downslope mass movement. Smaller-scale slides and slumps (tens of kilometres across) occur on the eastern margin, but they are subordinate to canyon, channel and fan systems. The western and central parts of the trough floor contain the Feni Sediment Ridge, a 600 km long contourite sediment build-up covered by large sediment waves trending sub-parallel to the dominant modern current pattern. Strong, northward-flowing bottom currents are thought to have eroded the base of the slope in the east and redeposited the sediments on the western margin and the trough floor. Mass wasting and terrigenous sediment input through canyons is regarded as the primary source of sediment in the region. The increase in the degree and frequency of canyon incision along the NE margin of the trough reflects increased terrigenous input from the Irish mainland and a possible glacial influence on the basin margin. The GLORIA images reflect a broad interplay of alongslope and downslope sediment transport processes in the Rockall Trough with sediments sourced from the NE margin and redistributed by currents along the western margin. Although alongslope and downslope processes are the major controlling factors, basin subsidence, Quaternary glaciations and glacio-eustatic sea-level fluctuations have also influenced the pattern of sedimentation in the Rockall Trough.
Slope failure features on the margins of the Rockall Trough
Authors: Shannon P. M. , O’Reilly B. M. , Readman P. W. , Jacob A. W. B. , Kenyon N.
Published: September 2007

A TOBI sidescan sonar survey in the Irish sector of the Rockall Trough reveals the presence of a range of slope failure features of various sizes and extent along both the eastern and western margins. A number of different types are identified. These include incipient cuspate slides, slab failures and evolved slides, and debris flows. It is suggested that the incipient cuspate slides, slab failures and evolved slides represent slope failure of muddy sediments whereas the failures that gave rise to debris flows lie on steeper slopes and may be of less muddy composition. Many of the slope failure features are relatively recent (probably <15 ka), although some evidence points towards either a prolonged period of movement or a number of phases of slope movement locally along the margins. A comprehensive understanding of the nature, distribution, age and controls on the formation of the slope failure features will be necessary in planning the likely location of sea-bed structures in the event of petroleum development in the region.
Sustainable groundwater development
Authors: Hiscock K. M. , Rivett M. O. , Davison R. M.
Published: September 2007

Estimated annual water availability per person in 2025 is likely to result in at least 400f the world’s 7.2 billion people facing serious problems with obtaining freshwater for agriculture, industry or human health (Gleick 2001). To meet present and future needs with the currently available surface and groundwater resources, while at the same time preserving terrestrial and aquatic ecosystems, will require a sustainable approach to managing water. This paper discusses the importance of groundwater resources in industrialized and developing countries, and the associated problems of over-abstraction and groundwater pollution, with the objective of defining sustainable groundwater development. It is concluded that sustainable groundwater development at global and local scales is achieved through the maintenance and protection of groundwater resources balanced against economic, environmental and human (social) benefits. This interpretation of sustainable groundwater development is incorporated into the methodologies currently emerging in Europe (the EU Water Framework Directive) and England and Wales (Catchment Abstraction Management Strategies). However, success in achieving future sustainable groundwater development will require a common understanding at the level of the individual based on information and education within a legislatory framework that promotes co-operation and self-responsibility.
Geophysical investigations of the thermal springs of Bath, England
Authors: McCann C. , Mann A. C. , McCann D. M. , Kellaway G. A.
Published: September 2007

The origin of the thermal springs of Bath (England) remains unknown. As part of a programme of research into the structure of the thermal aquifer, the Carboniferous Limestone, an urban reflection seismic survey has been carried out to explore the deep geology of the Bath area. Existing gravity data have been used to provisionally identify the seismic reflectors and to map the depth of the (interpreted) Carboniferous Limestone in the area around the springs. The new seismic data show that at a distance of 2.1 km south-west of the springs, the depth of the (interpreted) Carboniferous Limestone surface increases from 0.4 km below Ordnance Datum (OD) to 1.35 km below OD within a distance of 1.8 km, an average apparent dip of nearly 30 degrees. In all other directions from the springs, the Carboniferous Limestone surface is at a depth of 300 m or less below OD. The work described in this paper is part of a continuing research programme.
Groundwater resource management in eastern England: a quest for environmentally sustainable development
Authors: Burgess D.B.
Published: September 2007

The management of groundwater resources in England and Wales was initially based only on measures of the renewable resource. This has been extended to include the need to preserve the springs, river flows and surface water levels dependent on groundwater discharges as a key objective of a sustainable management of groundwater resources. The impacts of all new groundwater abstraction proposals on the surface water environment are now evaluated using a number of techniques, some of which are under further development. The sustainable management of groundwater catchments also includes the control of pumping from existing groundwater sources to meet agreed environmental targets. This approach is illustrated by examples of groundwater catchments managed to augment surface flows, to prevent saline intrusion and to preserve the integrity of wetland conservation sites.
Who needs sustainability?
Authors: Price M.
Published: September 2007

Three inescapable factors face us at the turn of the century. First, the climate, and with it the supply of water, is becoming more variable. Regardless of whether this variability is the result of man-made global warming, it seems to be with us. Secondly, demand for water will increase; in many countries domestic water use is currently less than 25 1/personday and needs to increase if living conditions are to improve. In Great Britain,
per capita
use of water is low compared with many other western countries — including those that pay for water on a metered basis — and it is certain to rise as living standards improve. Thirdly, concern for the environment is likely to increase. We can counter the first problem only by ensuring that we have adequate water storage; most water storage in Great Britain and the rest of the world is in the ground. We need to counter the second by recognizing that the vast majority of public water use is non-consumptive, but that very little waste water is re-used efficiently. We need to counter the third by welcoming the concern but ensuring that the response is sensible. We must be prepared to question some of the accepted wisdom of the environmental movement, and remember that many of the developments in human history were non-sustainable. Do they represent environmental disasters, or human progress?
Sustainable groundwater development in arid, high Andean basins
Authors: Anderson Mark , Low Rob , Foot Stephen
Published: September 2007

Mining is an important part of the economy of Chile. A high proportion of mines are located in remote, high altitude, extremely arid environments in northern Chile. The demands of the mining industry for potable and ore-processing water, along with existing longer term demands, mean that water has a high commercial value in this region. Set against this is the desire to conserve the unique flora and fauna, highlighted by the existence of a number of conservation sites of international importance. A typical case study charting the investigation of an aquifer in this region [the Monturaqui-Negrillar-Tilopozo (MNT) aquifer] and the development of a plan for groundwater use observing the requirement for sustainability is presented. The important aspects of the geology and hydrogeology of the aquifer are presented, and a description is given of the techniques used to arrive at a sustainable groundwater development strategy. The unusual characteristics of the aquifer meant that the use of spatially distributed time-variant numerical models to identify a sustainable groundwater abstraction strategy was necessary. The abstraction strategy will enable sustainable abstraction of a significant volume of groundwater from the MNT basin, taking advantage of the high storage to recharge/discharge ratio of the aquifer.
Constraints on sustainable development of arsenic-bearing aquifers in southern Bangladesh. Part 1: A conceptual model of arsenic in the aquifer
Authors: Burgess W. G. , Burren M. , Perrin J. , Ahmed K. M.
Published: September 2007

Arsenic is widespread in groundwater of the Holocene alluvial aquifers in southern Bangladesh, yet its concentration is highly variable spatially and with depth. A conceptual model of arsenic in the aquifer is proposed, as a basis for addressing questions concerning sustainability of groundwater development. Patterns and profiles of arsenic distribution in the aquifer have been determined at Meherpur in western Bangladesh, over an area of 15 km
2
and a depth range of 15–225 m. The hydrochemical and hydraulic environments of arsenic occurrence have been established. The conceptual model incorporates the conditions of arsenic release to groundwater, the depth distribution of the arsenic source, likely sedimentological controls on the lateral discontinuity of the arsenic source, and the hydraulic regime imposed by pumping from the hydrogeologically leaky, multi-layered aquifer. Reducing conditions, conducive to arsenic release from sedimentary iron oxyhydroxides, are widespread. The arsenic source occurs at a distinct horizon at a depth of about 20m, but is laterally discontinuous. The catchments of shallow, hand-pumped tubewells (HTWs) are limited in extent by vertical leakage. Arsenic concentration in water pumped from tubewells depends on the depth separation between the HTW screen and the arsenic source, the overlap between the HTW catchment and the arsenic source layer, and the duration of pumping. Implications are drawn for treatment, tubewell location and design, monitoring, and predictive modelling.
Constraints on sustainable development of arsenic-bearing aquifers in southern Bangladesh. Part 2: Preliminary models of arsenic variability in pumped groundwater
Authors: Cuthbert M. O. , Burgess W. G. , Connell L.
Published: September 2007

Numerical models of groundwater flow and arsenic transport to tubewells in southern Bangladesh have been developed, based on a conceptual model derived from field observations. The catchment of a single hand-pumped tubewell (HTW) is incorporated within a model domain 8110m
2
in area and 60m thick. Three tubewell specifications represent typical Bangladesh HTW designs. Constant-concentration cells act as a single-layered arsenic source, arranged to represent the observed depth distribution of arsenic in the aquifer and the range of possible patterns of overlap between HTW catchments and discontinuous zones of arsenic release from sediment to groundwater. A variety of sorption regimes is simulated, and sensitivity to sorption is illustrated. Boundary conditions are modified to simulate the effects of deep production wells. The models reproduce the observed scale and range of arsenic concentration in groundwater pumped from HTWs, and demonstrate likely long-term trends. Breakthrough of arsenic to HTWs may occur a few years after the start of pumping, but at many tubewells the concentration of arsenic could continue to rise significantly over tens to hundreds of years. Spatial distributions and depth profiles of arsenic in groundwater from tubewells should be viewed as transient in the long term. These preliminary models allow implications for the sustainability of the shallow alluvial aquifer to be quantified provisionally. The mechanisms and scale of sorption of arsenic by the aquifer sediments remain as significant uncertainties.
Assessing the impact of groundwater abstractions on river flows
Authors: Kirk S. , Herbert A. W.
Published: September 2007

Groundwater abstractions affect the water balance in catchments of rivers in hydraulic continuity with groundwater and may lead to reductions in river baseflow. The Environment Agency issues licences for groundwater abstractions and takes into account the risk of such adverse impacts when deciding whether to grant licences and what conditions to associate with each licence. Assessing the impact of a particular licence is a difficult task, but analytical solutions to idealizations of the complex river-aquifer interaction can help guide such judgements. This paper presents a brief review of available analytical solutions and discusses their applicability to real groundwater systems. The most useful analytical solutions (developed by Theis, Hantush and Stang) have been incorporated into a spreadsheet and a new methodology has been made available to support Environment Agency hydrogeologists working in abstraction licensing. This offers a consistent approach to making an initial evaluation of the impact of groundwater abstraction on river flow that may be applied across the diverse hydrogeological systems found throughout the Environment Agency Regions of England and Wales. The use of analytical solutions in this methodology inevitably represents a significant simplification of what is generally a very complex issue, and the limitations of the new methodology are emphasized.
Determination of hydraulic boundary conditions for the interaction between surface water and groundwater
Authors: Macheleidt W. , Nestler W. , Grischek T.
Published: September 2007

The main determinants of the interaction between surface water and groundwater are the distribution of areas with different infiltration rates, the thickness of sediment layers and the hydraulic head gradient. These conditions determine the volume and velocity of infiltrating water which, together with the direction of water flow, are required to model the interaction processes. Due to difficulties with measurement, only the direction of water flow is usually determined and boundary conditions are estimated from simplified assumptions. Field techniques have now been developed that help characterize surface water-groundwater interaction. Results from field experiments using a percussion probe and a large-scale laboratory column experiment set up to simulate infiltration processes are presented. Measurements of the
222
Rn distribution in the column are used to determine infiltration velocities.
A simple analytical solution for unsaturated solute migration under dynamic water movement conditions and root zone effects
Authors: Connell L. D.
Published: September 2007

Vulnerability mapping involves an assessment of the potential for solute migration to the water table. Existing procedures rely on simple qualitative indices to calculate this migration potential. As an alternative to these vulnerability indices this paper presents a simple, analytical solution to the advection-dispersion equation. This solution is physically representative, in that it allows for the effects of root zone processes and climate-induced water movement variation on solute transport. The basis of this analytical solution is a spatially transformed advection-dispersion equation. The root zone is treated in a lumped fashion where a relation is developed for the solute concentration of water that has passed through the root zone that includes retardation, degradation and transpiration. This lumped root zone treatment is used in an existing analytical solution that is adapted so that it can be used for a transformed unsaturated advection-dispersion equation. The procedure is tested against hypothetical simulations with dynamic water movement conditions calculated using SWIMv2. The accuracy of the approach is found to be a function of the soil permeability. Where the dynamic variation is averaged out by the water movement process (such as in soils with moderate permeability) the method can accurately represent the transport process. For soils where surface conditions lead to significant variation in water content throughout the profile the technique is more approximate.