bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Folkestone Bed sands: microfabric and strength
Authors: Richards N. P. , Barton M. E. 
Published: November 2007

Abstract

The Folkestone Beds formation is a marine shallow-water deposit of Cretaceous age. It consists mostly of poorly lithified sands which classify onto the sand/sandstone borderline, having properties neither akin to the classical concept of an
engineering soil
nor being strong enough to be labelled a
rock
. Intact samples were obtained by block sampling at 17 locations. Studies of the microfabric were made from thin sections prepared after epoxy resin impregnation. Although predominantly quartzose, the samples have a very wide range of grain sizes, size distributions, porosity and grain contact relations. The random inter-relationships amongst the microfabric parameters suggest that shelf sands, such as this formation, do not fit the patterns reported for deeply buried, and hence more diagenetically altered, sandstones.

The majority are
weakly cemented
but samples from two locations possess negligible binding cement and are classed as
locked sands
. Measurements of the peak shear strength were carried out on air-dry samples of the intact sand using a 60 mm square, direct shear box. The peak shear strengths were strongly influenced by the intensity of interlocking: this factor being more significant than either porosity or total cement content. The samples possess a tensile strength, uniaxial compressive strengths up to 725 kPa and a cohesion intercept at zero normal stress in the shear box. The fabric cohesion reduces with increasing content of coarse sand and is very poorly developed in coarse sands.
Karstic groundwater flow characteristics in the Cretaceous Chalk aquifer, Northern Ireland
Authors: Barnes S. 
Published: November 2007

Abstract
The Cretaceous Chalk in Northern Ireland (Ulster White Limestone Formation) is a locally important aquifer for both public and private supply, yet little is known about its groundwater flow regime. This issue is important for the protection of existing groundwater abstractions and for the development of new sources as it will help determine groundwater vulnerability and resource potential in the Chalk. The subject has been addressed using hydrochemical variations from individual springs, together with artificial and natural water tracing techniques employed from river-sinks located at outcrop.
A common orientation has been established between traced groundwater flow routes and the dominant northwest-southeast fracture trend within the Ulster White Limestone Formation. Hydraulic gradient has also been shown to have little significance in controlling the flow direction, suggesting poor fracture connectivity and thus extreme aquifer heterogeneity. Tracer breakthrough curve characteristics and velocities (up to 2838 metres per day) are indicative of conduit rather than fracture flow. In addition, the highly variable water chemistry associated with all the proven river-sink supplied springs has been independently classified to meet conduit flow criteria. Conversely, the much less variable water chemistry associated with springs draining Chalk subcrop areas (with no influence from river-sinks) is consistent with a less active karstic regime.
In situ
determination of
G
hh
at Bothkennar using a novel seismic method
Authors: Hope V. S. , Clayton C. R. I. , Butcher A. P. 
Published: November 2007

Abstract

The paper describes a novel seismic method for determining the variation of velocity with depth of horizontally propagating, horizontally polarized shear waves (
S
h,h
). The technique exploits the curved paths of seismic waves in deposits with increasing velocity properties with depth. The new method has been applied at the soft clay test site at Bothkennar, and the results of this survey are compared with
S
h,h
and
S
v,h
wave velocity profiles obtained using conventional crosshole survey techniques at the site. The seismic data are further compared with the results of recently reported bender element tests on unconfined samples from the bedded and mottled Bothkennar clay. It is shown that, at the site investigated, the new method presents results comparable to those from the established field survey techniques. Neither the seismic nor the bender element data indicate significant stiffness anisotropy at the site.
Use of electrical imaging in site investigations for a railway tunnel through the Hallandsås Horst, Sweden
Authors: Dahlin Torleif , Bjelm Leif , Svensson Conny 
Published: November 2007

Abstract
Investigations over two major tectonic zones in the Hallandsås Horst, Southern Sweden were carried out in connection with a railway tunnelling project. A combination of resistivity imaging, core drilling and geophysical logging was found to provide a good overview of the variation in rock quality and detailed information on the engineering geological characteristics and genesis of the strata. Resistivity data, acquired along parallel lines over the zones using multi-electrode equipment, were processed by means of automatic inversion software to generate sections showing the variation of resistivity with depth. Wireline core drilling at selected points gave an almost complete core recovery, which revealed major sedimentary sequences and heavily weathered crystalline rocks that were previously unknown or only partially known despite conventional core drilling and percussion drilling. Geophysical borehole logging confirms the resistivity imaging results, and would be a particularly valuable complement to core logging in cases where significant core loss occurs.
Estimating transmissivity from surface resistivity soundings: an example from the Thames Gravels
Authors: MacDonald Alan M. , Burleigh James , Burgess William G. 
Published: November 2007

Abstract
Surface electrical soundings can be used to extrapolate pumping test results over an area. Using the Dar Zarrouk parameters, a constant can be found which will simply translate resistivity to transmissivity, provided that either clay content or porosity is the primary control on resistivity and permeability. The applicability of the technique is tested on the gravel aquifer at Desborough Island, UK.
Glacial hazard assessment at Tsho Rolpa, Rolwaling, Central Nepal
Authors: Reynolds John M. 
Published: November 2007

Recession of glaciers throughout the Himalayas is resulting in the development of a growing number of high-altitude proglacial lakes that are retained behind natural moraine dams. Some of these have failed catastrophically and the consequential Glacier Lake Outburst Floods (GLOFs) have resulted in substantial damage and loss of life downstream. With growing populations in remote valleys coupled with the demand for substantial growth in the capacity for hydro-electric power for export, the risk of further disasters is increasing. Accordingly, His Majesty's Government of Nepal has undertaken a series of studies since 1985 to investigate the risks associated with such glacial lakes. This photofeature encapsulates aspects of the work undertaken between 1994 and 1997 at Tsho Rolpa, which is thought generally to be the largest and most dangerous glacial lake in Nepal. The present project at Tsho Rolpa is the first of its kind in Nepal and represents the first time that such detailed glacial hazard assessment has been undertaken through to the development of a full remediation scheme in Nepal.
Tsho Rolpa lies about 110 km north east of Kathmandu at the eastern end of the Rolwaling Valley (Fig. 1) and immediately south of Gauri Sankar (7146 m). The lake (Fig. 2) is about 3.5 km long by 0.5 km wide and is up to 135 m deep. It is fed by Trakarding Glacier (Fig. 3) to the southeast which is itself a composite glacier supplied by several glaciers from among the peaks to the east and south east of
The role of calcium carbonate in the compressibility of Pliocene lacustrine deposits
Authors: Bozzano Francesca , Marcoccia Sabrina , Barbieri Maurizio 
Published: November 2007

Abstract

The results of a study on the influence of calcium carbonate content on the physical characteristics and compressibility parameters of Pliocene lacustrine deposits are discussed. The origin of CaCO
3
has been investigated and it is thought to have been precipitated, after consolidation, as cement which partially filled the void spaces between soil particles. Average CaCO
3
content was about 22% along a 116.5 m deep vertical profile. The CaCO
3
in the clay and silt fractions (CaCO
3
*) was considered the best available estimate of that acting as cement. The relationships reported in the literature between Atterberg limits and CaCO
3
content have been statistically confirmed by the tests performed on decalcified laboratory samples, but not by those performed on natural samples due to lithological heterogeneities. Yield stress, constrained modulus, swelling index and microstructure resistance were affected by CaCO
3
* content in the stress range lower than yield stress. In the stress range higher than σ′
vy
, no relationship was observed between C
c
and CaCO
3
, while an inverse relationship between C
s
and CaCO
3
was observed in both the natural and remoulded samples and thus is thought to be due to the presence of inactive calcite. Moreover, the remoulded samples also show an increase in C
s
with respect to the natural ones. From these findings it follows that the yield stress for cemented materials corresponds to the partial disruption of the structure.
Weathering simulation for durability assessment of the in-service performance of construction materials
Authors: Taylor-Firth A. , Laycock E. A. 
Published: November 2007

Abstract
A facility is described which is capable of simulating climatic parameters and pollution activated effects. These can be induced simultaneously or individually and in real-time or cyclic mode. The behaviour of materials and associated construction technologies can be continuously monitored by visual inspection and computer controlled data acquisition and analysis systems, thus making possible realistic prediction of ‘in-service performance’ and probable durability.
Subsidence caused by gypsum dissolution at Ripon, North Yorkshire
Authors: Cooper Anthony H. , Waltham Antony C. 
Published: November 2007

In the afternoon of Wednesday 23 April 1997, a large subsidence crater opened up in front of a house on Ure Bank Terrace, on the northern outskirts of Ripon in North Yorkshire. Overnight its sides collapsed inwards, so that the hole had doubled in size by the next morning (Fig. 1). The subsidence crater was then 10 m in diam- eter, and 5.5 m deep to a choke of debris overlain by water 1 m deep. Its sudden appearance was the cause of considerable concern to the occupants of the adjacent house, and the event was widely reported in the national press and media.
A subsidence hollow was mapped at this site by the 1856 Ordnance Survey and documented by Cooper (1986). More subsidence had occurred at the Ure Bank site in previous years, but this latest collapse had rather more impact. Creeping movement of the soil towards the new hole meant that the adjacent house was destined for demolition. The event was the latest of a series of ground collapses that have occurred, at an average rate of about one per year, in and around the city of Ripon. While they are little more than an inconvenience in farmland, they have the potential to cause serious damage when they occur in built-up areas.
The immediate cause of the Ure Bank subsidence was the downward movement of soil, drift and recent fill into actively expanding voids within the ground. Ultimately, it was caused by the partial collapse of a cave
Rockfall checkfences at Pen-y-Clip on the A55 North Wales Coast Road, UK
Authors: Nichol Douglas 
Published: November 2007

The A55 North Wales Coast Road between Chester and Holyhead forms a strategic part of Euroroute E22 (Sassnitz to Dublin) and provides a major artery to the British and European motorway network for traffic arising not only from North Wales but also from Ireland via the international ferry terminal at Holyhead (Fig. 1). The highway comprises 145km of modern dual carriageway. Unfortunately rockfall activity poses a significant geohazard in the vicinity of the mountainous headland at Pen-y-Clip and especially affects the westbound carriageway approaches to the road tunnel through the headland (Fig. 2). This area has a history of high rockfall frequency and, in 1984, a rock avalanche blocked the headland road and caused a two week closure (McWilliam 1991). At Pen-y-Clip, steep slopes and adverse geological factors combine to create potentially unsafe ground above the road.
The Pen-y-Clip promontory constitutes a natural obstacle along the coastal plain and routes tend to converge towards the seaward point of the headland. The Pen-y-Clip road tunnel, opened to traffic in October 1993, was driven through the headland and a wide variety of rockfall protection measures including rockfall checkfences were incorporated into the design and construction of the project (Brady et al. 1994). The checkfences were installed in advance of construction to protect the workers on the scheme and to safeguard the headland road particularly against rockfall initiated by blasting during construction.
Geologically, the headland at Pen-y-Clip comprises a core of igneous rocks associated with the Penmaenmawr intrusion (Fig. 3). The intrusion measures
Modelling the evolution of minewater pollution at Polkemmet Colliery, Almond catchment, Scotland
Authors: Chen M. , Soulsby C. , Younger P. L. 
Published: November 2007

Abstract

Polluted discharges from abandoned mines are a major cause of freshwater pollution in central Scotland, often contributing high Fe, SO
4
2-
and acidity to receiving streams. The Central coalfield has been extensively mined for over a century and Polkemmet was the last colliery to close in 1985. Recent monitoring indicates that the rate of groundwater recovery is approximately 0.15 to 0.2 m per week. Without intervention, this trend would result in complete recovery by 2000 and probable discharge into the River Almond. Geochemical modelling indicates that pyrite oxidation, calcite dissolution and goethite precipitation are primarily responsible for the evolution of groundwater chemistry currently observed at Polkemmet. Predictive modelling using PHREEQE suggests that unregulated minewater discharges will have marked effects in the River Almond, with goethite being initially precipitated at a rate of up to 36 kg/day, dissolved sulphate concentrations ranging between 170 and 800 mg/l and pH being depressed to 6.5. Combined active lime flocculation and passive aerobic wetlands may be the most effective means of treating the predicted minewater discharges. Keywords: abandoned mines, hydrochemistry, surface water, underground mining, water quality
Crag aquifer characteristics and water balance for the Thurne catchment, northeast Norfolk
Authors: Holman I. P. , Hiscock K. M. , Chroston P. N. 
Published: November 2007

Abstract

A study of the hydrogeological controls on the Pleistocene Crag aquifer in northeast Norfolk is reported. Geophysical methods, in particular multichannel seismic reflection profiling, have provided useful information on the internal structure of the aquifer. The Crag represents a layered aquifer, with horizons of clay and silt strata able to limit the overall vertical permeability of the aquifer. A laterally continuous clay horizon is identified at around -25 mOD and is mapped as far as the coast. Shallow wells and borehotes in the Crag are prone to contamination. Nitrate is widely recorded, with concentrations of typically up to 150 mg l
-1
in shallow wells, derived from mainly agricultural sources, although deeper boreholes are less affected given the restricted downward movement of ground-water. The land drainage systems within this lowland area dominate the hydrology and hydrogeology of the catchment. Surface flows into the River Thurne are controlled by the operation of drainage pumps and a catchment water balance demonstrates that groundwater principally discharges to the drainage ditches within the extensive arable and grazing marshes in the catchment.
Hydrogeology and European legislation
Authors: Sheils A. K. 
Published: November 2007

Abstract
The paper distinguishes between the definitions of ground water in the UK and in European Community (EC) law. Each of the three main EC directives affecting groundwater is considered in turn, together with the associated official circulars. Examples are given of some problems of interpretation of the EC Groundwater Directive.
Details are included of a new national classification scheme for dangerous substances reaching groundwater. Threshold values are set out in a formal 'direction' for the criteria of low toxicity, persistence, and bioaccumulation.
Recent and possible EC developments relating to ground water are also indicated. For example a Ministerial Seminar held at The Hague in late 1991 proposed an action programme to be prepared by the EC Commission by mid 1993 and to be implemented by 2000; the setting up of international expert groups and possible moves towards harmonizing the monitoring of groundwater.
New European legislation for the protection of ground water may be expected within the next few years. However, further EC action is likely to depend on more general questions relating to the role of the Community.
High-purity limestones in England and Wales
Authors: Harrison David J. 
Published: November 2007

Abstract
Most limestone is used in the construction industry principally as an aggregate and in the manufacture of cement. A high degree of chemical purity in these limestones is not usually necessary although some restrictions on contaminants may be made. Around 10 million tonnes of limestones are used annually for industrial purposes which require ‘high-purity’ limestone or limestones of specific physical properties which are, at least to some extent, related to the purity of the limestone. Such limestones are used in the iron and steel industry, in the chemicals industry, in glass making, in fillers and pigments and in a wide range of other industries. An increasingly important use of ‘high-purity’ limestone is in flue gas desulphurization schemes in power generation plants.
This paper describes the broad geological resources of high-purity limestone in England and Wales. Most high-purity deposits occur within the Carboniferous Limestone of the Peak District, the Mendips, South and North Wales, parts of the northern Pennines and around the fringes of the Lake District. Large areas of the Chalk outcrop also contain high-purity resources, particularly part of the Upper Chalk outcrop of southern England and in the Burnham and Welton chalk outcrops of northern England. The dolomites and dolomitic limestones of the Permian Magnesian Limestone also locally contain consistently pure deposits. Jurassic, Devonian and Silurian limestones are mainly of low chemical grade.
Hydrogeological studies on the Rock of Gibraltar
Authors: Wright E. P. , Rose E. P. F. , Perez M. 
Published: November 2007

Abstract

The hydrogeology of an aquifer within the dolomite/limestone formation that dominates the Gibraltar peninsula has been studied with a view to the possible development of contained groundwater resources taht occur as a thin lens of fresh water overlying sea water. Recharge rates (calculated by soil moisture and chloride balance) could be of the order of 400 000 m
3
per year. This is significant in relation to the current demand for potable water of some 1 000 000 m
3
per year, 900f which is provided by desalination. Exploration drilling focused on fracture zones, but tested vertical boreholes generally demonstrated a rapid decline in water quality, even where drawdowns were very small. Exploration also revealed oil pollution of the groundwater within the Rock, most significantly near the Naval Dockyards to the soutwest and less so beneath the North Face. The greatest potential for sustained discharge was found to occur in shallowly inclined boreholes. Discharge quality was clearly sensitive to a range of factors including immediate rainfall events, tidal fluctuations, vertical permeability of the aquifer, borehole design and anthropogenic effects. Further studies are needed to determine the significance of these controls and to assess whether development of the likely resources is practicable.
Editorial
Authors: West Graham 
Published: November 2007

Among the recurring suggestions listed in the responses to the 1993 membership survey undertaken by the Society, was the request for a higher profile for hydrogeology, and the inclusion of environmental geology. Hydrogeology has always featured in the QJEG (a paper on groundwater in Tehran appeared as early as Volume 1, Part 3) but the journal has not published in the environmental geology field before. We feel, however, that there is considerable potential for publications in both fields, and it has been decided that, as there are a number of excellent hydrogeological papers awaiting publication at the moment, a special Hydrogeological thematic part will be issued alongside Part 3 of the QJEG this year at no extra cost to subscribers. In addition, it is proposed to include environmental geology and waste management within the scope of the journal from now on. Readers of the QJEG can help this exciting new development by spreading the word that papers on the engineering geological or hydrogeological aspects of environmental protection and waste management can now be considered for publication.
Construction materials have always been of interest and concern to engineering geologists and this has been reflected in the pages of the QJEG from its inception. As early as Volume 1, No. 2, we had a seminal paper on the polishing of roadstones that described a test that is still in use today and which, over a quarter of a century, has contributed greatly to road safety in many countries. Construction materials continue to
Geotechnical characterization of blended coal tailings for construction and rehabilitation work
Authors: Indraratna B. 
Published: November 2007

Abstract
Coarse and fine refuse is produced by various coal processing equipment. For instance, fine tailings (100-500µm) are produced by froth flotation cells, whereas coarse fractions (up to 50 mm) constitute cyclone rejects. The relatively wet fine tailings have limited use in construction activities and they are generally pumped as slurries into tailings ponds. The coarse rejects have a greater engineering applicability and are utilized in the construction of tailings dams, mine access roads as well as for landfill and ballast. This study investigates the fundamental engineering properties of blended tailings, where- by appropriate fractions of flotation tailings are mixed with cyclone rejects to produce an acceptable construction or rehabilitation fill. In particular, a practical procedure to optimize the blended ratios is proposed on the basis of fundamental geotechnical testing. The applications of relevant tests are described, including Proctor compaction, California Bearing Ratios, triaxial and consolidation tests. The results confirm that blending of fines with coarse rejects enables enhanced dry densities associated with reduced permeabilities, higher shear and compressive strengths, lower consolidation settlements and increased bearing capacities. The addition of a small quantity of cement (2-5%) further improves the engineering properties of the blended matrix. The practical findings of this study should encourage coal processing plants to modify their existing disposal methods to adopt more efficient co-disposal schemes. Optimization of procedures for discarding fine and coarse rejects together would generate substantial savings, with regard to dewatering of wet tailings and rehandling of distinctly different waste gradations.