bluuebunny/crossref_metadata_2025_split huggingface dataset:
The hydrogeology of the Enfield-Haringey artificial recharge scheme, north London
Authors: O'Shea M. J. , Baxter K. M. , Charalambous A. N. 
Published: November 2007

Abstract
The Enfield-Haringey artificial recharge scheme comprises 23 abstraction/recharge boreholes located between Enfield and Haringey in north London. It is a strategic groundwater development aimed at increasing drought yields to meet the 'target level of service' defined by OFWAT for availability of water resources. The hydrogeology of the scheme, revealed by the drilling and testing of 15 new production boreholes is described and its strategic use summarized. The hydrochemistry of the groundwater in the Chalk and Basal Sands aquifer is briefly considered and the likely effects of re-saturation after recharge on the quality of the pumped groundwater is commented on.
This and previous studies have led to a better understanding of the aquifer system and the hydraulic relationship between the Basal Sands and the underlying Chalk. Intensive exploitation in the past led to some dewatering but reduction in abstraction since the 1950s has allowed water levels to recover, a process that is continuing. In most of the Enfield-Haringey area the aquifer is still only partially saturated, hence the potential for artificial recharge. The Chalk aquifer has been found to be typically anisotropic and heterogeneous with the upper 30–40 m being productive. Acidization was found to produce significant increases in well yields. Chalk groundwaters are mainly of a calcium bicarbonate type while those of the overlying Basal Sands are dominated by sulphate. Both groundwaters become progressively richer in sodium at the expense of calcium from north to south, in the direction of groundwater flow and towards more deeply confining conditions.
An empirical liquid permeability—gas permeability correlation for use in aquifer properties studies
Authors: Bloomfield J. P. , Williams A. T. 
Published: November 2007

Abstract

Laboratory permeability studies can contribute significantly to the quantification of aquifer heterogeneity. However, intrinsic permeabilities obtained by standard core analysis techniques using gas are different from those obtained using water. This is because gas measurements may be affected by a molecular phenomenon known as gas slippage. An empirical correlation is presented for liquid and gas permeability measurements obtained for a suite of Permo-Triassic sandstones and shales from the Sherwood Sandstone Group of northern England. Liquid permeability tests were performed using synthetic formation brines and deionized water. Gas permeability tests used nitrogen as the permeant. Liquid permeabilites,
k
l
, ranged from 9.0 x 10
-19
m
2
to 2.4 x 10
-12
m
2
and gas permeabilites, k
g
, ranged from 1.7 x 10
-17
m
2
to 2.6 x 10
-12
m
2
.The liquid and gas permeability data exhibit log-normal frequency distributions; the log transformed liquid and gas permeability data have means of 5.1 x 10
-16
m
2
and 4.3 x 10
-15
m
2
respectively. A linear least-squares fit to the data has the form log
10
k
l
= 1.17log
10
k
g
+ 1.51.
k
l
/
k
g
ratios, in the range 0.03 to 0.9, indicate that Hagen-Poiseuille type models may not provide appropriate descriptions of gas flow in the Sherwood Sandstone.
Permeability impairment around boreholes in micaceous aquiferes
Authors: Blackwell I. M. , Howsam P. , Walker M. J. 
Published: November 2007

Abstract
A number of possible mechanisms, both physical and chemical, are postulated as being potentially damaging to borehole performance in micaceous aquifers. Laboratory studies have been undertaken to assessthe degree to whichthese mechanisms are operative, and the extent of permeability damage which occurs as a result. Some of the processes studied are unique to micaceous formations, while others are enhanced where mica is present. Two key processes identified by the study are: (i)mineralogical and structural alteration of mica particles as a result of increased groundwater salinity; and (ii) mixing of formation sands, either between layers, or with gravel pack material. The studies together with field evidence show that both of these processes can cause a significant reduction in permeability in the vicinity of a borehole, leading to a deterioration in borehole performance. The degree of deterioration which can result from each of the processes is assessed, and recommendations for operation, maintenance and rehabilitation, to minimize damage are made.
Structural damage associated with land subsidence caused by deep well pumping in Bangkok, Thailand
Authors: Eddleston M. 
Published: November 2007

Bangkok, the capital city of Thailand, has experienced rapid growth over the last two decades and is relatively prosperous by Asian standards. The city is situated in the lower half of the flat deltaic plain of the River Chao Phraya and lies at ground elevations of between 0.5 and 1.5m above mean sea level, although some areas are even lower and lie below mean sea level. Drainage of the area is poor and takes place by way a network of sluggishly flowing waterways known as ‘klongs’.

A recent report by the Asian Institute of Technology (A. S. Balasubramaniam
et al.
1992)indicated that subsidence phenomena were beginning to be experienced in the city in the early 1960s when rapid population growth resulted in excessive deep well pumping to satisfy the increased demand for water. At present there are approximately 15000 tube wells drilled through the upper 200 m of superficial deposits, with approximately 600 new abstraction licences granted in 1993.

The area in and around the city is underlain by recent marine clay (known as Bangkok Clay) which overlies older deposits of Pleistocene age. These older deposits, which comprise an upper stratum of stiff clay overlying alternating clays, sands and beds of gravel, are of significant thickness. The total depth of superficial deposits overlying the basement rocks in the Bangkok area varies between 500 and 2000m (Anon 1981).
The upper sequence of very soft to soft Bangkok Clay and the underlying stiff clay stratum is consistent over much of Bangkok and
Mineralogy, fabric properties and classification of weathered granites in Hong Kong
Authors: Irfan T. Y. 
Published: November 2007

Abstract
Deeply weathered granitic rocks are encountered in many engineering works in Hong Kong. To date, the engineering properties and behaviour of these granites, and the soils formed from them, have been poorly related to their basic mineralogical and fabric characteristics. In this paper, a model for weathering of granites is established and, based on this, modifications are proposed to the material and mass weathering schemes commonly adopted in Hung Kong for the characterization of weathered granite in engineering uses. A number of chemical indices have been found to be good indicators of chemical weathering whereas the micro-petrographic indices can be used to characterize most fabric elements of weathered granites. Care in the testing and interpretation of test results is required for soils of granitic origin because of specific mineralogy and fabric that is developed.
A comprehensive method of rock mass characterization for indicating natural slope instability
Authors: Mazzoccola D. F. , Hudson J. A. 
Published: November 2007

Abstract
The purpose of this paper is to present an application of the Rock Engineering Systems (RES) methodology for developing a new rock mass classification, sensitive to large-scale instability in natural slopes and suitable for indicating critical sites. In the area under study, located in the Italian Central Alps, and in most natural slopes, analysis is complicated by lack of data, geological complexity, scale of the instability phenomena and the high number of interacting factors. In order to be able to have a structured approach to such complexity, a comprehensive method based on the RES approach was adopted. This is an objective-based approach which allows the utilization of all the information related to the project, tailoring the classification to the actual circumstances. Hence those parameters which are particularly active at the site can be evaluated and the importance of their interactions established.
Following this approach, 19 parameters relating to the general environment and to the rock mass characteristics are considered. Their reciprocal causes and effects are analysed in order to weight each parameter according to its degree of interactivity in the system. The final definition of the rock mass instability index takes into account the variability of the parameter values for different slopes in assigning ratings to different classes of parameter values. In parallel, a predictability rating is computed, according to the presence in the field of a number of ‘indicators of instability’. Both indices allow discrimination of critical slopes, and are in good agreement with field evidence demonstrating the value of the approach.
Progressive weathering and degradation of mudstone in a coastal landslide
Authors: Hodgson R. L. P. , Grainger P. , Kalaugher P. G. 
Published: November 2007

Abstract
The relationship between the processes of landsliding of a coastal cliffand the progressive weathering of a Permo-Triassic mudstone is examined. The landslide, on the southern coast of Devon in southwest England, includes rockfalls, mudflows and a large mudslide. A stepped profile is produced by occasional stronger beds within the mudstone, which is also capped by conglomerate. A combination of partially weathered clasts and disaggregated matrix develops in debris fans and mudflows which feed the main mudslide. Weathering, which increases the plasticity index of the degrading mudstone, is found to be crucial to the general profile being maintained. If the plasticity index becomes too high, mudflows are inhibited because too much water is required, while too low a plasticity index results in material which is reluctant to flow on the slopes beneath the main cliff.
The determination of rock material properties to predict the performance of machine excavation in tunnels
Authors: Arthur C. D. 
Published: November 2007

Abstract
The assessment of rock material properties is a critical element in any site investigation for the planning and construction of a tunnel through rock strata. This is irrespective of the number of rock strata involved and crucial to the determination of ground reference conditions as detailed in CIRIA Report No. 79 (1978).
An extensive suite of laboratory tests is combined with a comprehensive literature search in order to investigate the interrelationships between some commonly cited rock parameters. The suite includes Shore Scleroscope Rebound Values and results from a modified form of the Cerchar Abrasivity Test. In addition, the benefits from mineralogical analyses of rock samples are considered.
Rock material strength and hardness, with regard to common tunnel excavation techniques is found to be a combination of shear and tensile strength and can respectively be designated as cutting strength and abrasivity. An overall classification system is proposed which incorporates these parameters into an unambiguous notation in order to clarify test data and facilitate interpretation. By an appraisal of each testing technique in respect of relative costs and applicability to rock failure under machine excavation forces an incremental approach for rock testing programme is constructed in the form of a flow chart. The model proposes how the efficiency of current test programmes can be improved thus enabling more confident predictions of material properties in single or multi-strata ground along a proposed tunnel route.
Discussion on ‘Chalk fracture system characteristics: implications for flow and solute transport’
Authors: Younger P. L. , Elliot T. 
Published: November 2007

M. PRICE writes: Younger & Elliot (1995) used a radon diffusion model to derive apertures and field measurements to determine spacings for fissures (discontinuities through which flow takes place) in the Chalk. Their paper confirmed much existing knowledge, but when they attempted to use their data to calculate hydraulic conductivity values for chalk, they made a fundamental error that invalidated the main conclusions.
Although there are various assumptions, the average estimates of 0.45mm for the apertures and 9.4/m for the frequencies of fissures are in line with expectations. Applying these results to linear laminar flow in three orthogonal sets of smooth, plane, parallel-plate fissures gives a theoretical fissure porosity of 1.35 per cent and, for pure water at around 10°C, a hydraulic conductivity of 98 m/day. The porosity value is similar to the specific yield of much of the Chalk, but this hydraulic conductivity is much higher than is seen for the bulk of the Chalk in the absence of secondary (solutionenlarged) fissures (Price 1987).
However, in the paper, Younger & Elliot derived a value of hydraulic conductivity of 0.001 m/day. They therefore concluded that these fissure apertures and spacings could not explain the hydraulic conductivity of the Chalk even in interfluve areas (p. $46), and that much larger flow conduits must be present to explain the observed hydraulic conductivity values for Chalk beneath valleys. This difficulty is attributable to a simple error; their equation (11) yields results in m/see, not m/day as stated, so the calculated hydraulic conductivity values.
Plenmeller opencast coal site: a geotechnical and planning case study
Authors: Hughes D. B. , Norbury D. R. 
Published: November 2007

Abstract
Plenmeller is a remote upland opencast site in Northumberland designed to produce just over 2 million tonnes of coal during eight years of production. The complex ground conditions comprise thick peat and glacial deposits, overlying much faulted and steeply dipping Coal Measures strata. Previous under- ground workings, high groundwater levels and associated sub- surface reservoirs of water are also present. In order to mine and export the coal off-site, extensive infrastructure works were necessary including impounding embankments for lagoons, public road diversions, an overland conveyor with a tunnel and major river crossing, coal screening and crushing plant and a rapid loading bunker with associated railway sidings.
A lengthy planning history included a public inquiry and a high court heating before coal production commenced in August 1991. Imposed planning constraints required modifica- tions to the development, additional construction works and restoration measures. The combination of the site location, infrastructure requirements and planning constraints gave rise to the need for a wide range of ancillary civil engineering works; this was one of the most extensive programmes in connection with an opencast project in the UK. These engineering works in turn required a substantial geotechnical input. This paper presents a general account of the extensive ground investiga- tions and construction works carried out at Plenmeller, and briefly discusses some geotechnical aspects of the site operations and the construction works.
Troglodyte dwellings of the Loire Valley, France
Authors: Forster A. , Forster S. C. 
Published: November 2007

The Loire region of France (Fig. 1) is famous for its many chateaux which represent not only a pinnacle in art and architecture but also are a testimony to the excellence of the local building stone. The Saumur region of the Loire valley has an estimated 1000 km of quarried limestone galleries which were excavated from the 1lth to the 19th century. The stone has been used in buildings ranging from grand chateaux to simple domestic, commercial and agricultural buildings (Bailey 1993) (Fig. 2).
The stone is extracted from thickly bedded, fine-grained Cretaceous limestones of Turonian age, mainly the Tuffeux Jaune of the Upper Turonian or the Craie Micacée of the Middle Turonian (Alcaydé et al. 1976). It owes its wide usage to the fact that it has ideal engineering properties for a dimension stone since it is stronger and more resistant to weathering than ordinary Cretaceous Chalk but not so strong as to be difficult to quarry or carve into decorative features. The stone occurs in deposits with widely to very widely spaced bedding and joint discontinuities which enable it to have been mined in a manner similar to that of the Jurassic, Bath Stone of England.The value of the stone does not lie solely in its architectural or constructional attributes. The abandoned mines remain as very stable underground spaces by virtue of their exceptionally wide bedding and joint spacing. They are relatively dry and, in common with most underground spaces, possess a constant temperature. Thus, they have found
A visco-plastic model for slope analysis applied to a mudslide in Cortina d'Ampezzo, Italy
Authors: Angeli, Maceo-Giovanni , Gasparetto, Paolo , Menotti, Riccardo Massimiliano , Pasuto Alessandro , Silvano Sandro 
Published: November 2007

Abstract
This paper describes a visco-plastic model which, using recorded groundwater levels, is capable of simulating the velocity trend in landslides. It also deals with the phenomenon of shear strength regain that occurs in montmorillonitic clays constituting slopes during periods when landslides are stationary. The model has been validated with long-term observations of a clay slope affected by a mudslide.
Determination of the intact dry density of irregular chalk lumps: a new method
Authors: Lamont-Black J. , Mortimore R. N. 
Published: November 2007

Abstract

A simple, accurate and reliable method of measuring intact dry density (IDD) on small samples of chalk is described. The method proposed employs wax-sealing and water displacement in a eureka pot and is compared with five other methods, including that recommended in the British Standard. The method of laboratory measurement proposed is capable of achieving an accuracy of ±0.025 mg/m
3
, which is necessary in order to distinguish small scale natural density variations. These density variations can also be detected qualitatively with simple techniques, i.e. a geological pick.
Rapid prediction of Building Research Establishment limestone durability class from porosity and saturation
Authors: Moh'd Basem K. , Howarth Richard J. , Bland Christine H. 
Published: November 2007

Abstract

The development of a rapid, non-parametric, and slightly conservative predictor for the estimation of probable weight loss in the standard Building Research Establishment sodium sulphate crystallisation test, and hence of estimated limestone durability class, based on [Porosity
Saturation
]
0.5
is described. The time saving offered by application of the look-up tables provided here reduces the 3–4 weeks required for the Building Research Establishment crystallization weight loss test to a matter of hours and offers considerable practical advantage for rapid assessment of the suitability of limestone building stones quarried abroad (e.g. in Jordan) for use in the salt weathering conditions of the UK. However, there is a relatively large variance associated with this estimator (particularly when the microporosity coefficient exceeds 0.65) and in critical cases it should be followed up by confirmatory use of the standard crystallization weight loss test.
Locally derived earthquake ground motion attenuation relations for Jordan and conterminous areas
Authors: Husein Malkawi Abdallah I. , Fahmi Khalid J. 
Published: November 2007

Abstract

The most recent catalogue of earthquakes in Jordan and conterminous areas is used to derive formulae for the principal seismic ground motion parameters of peak ground acceleration (PGA), surface wave magnitude (M
s
), Mercalli intensity (I
0
(MM)), and epicentral distance (R). In this context, empirical relations characterizing earthquake ground motion attenuation in Jordan are developed. The main purpose of this paper is to assist engineers in estimating ground motion parameters in the pre-planning and design stages of construction as well as to help seismologists in decisions concerning the installation and operation of earthquake strong motion instrumentation around the country.
An integrated study of controls on solute transport in the Lincolnshire limestone
Authors: Lloyd J. W. , Greswell R. , Williams G. M. , Ward R. S. , Mackay R. , Riley M. 
Published: November 2007

Abstract
A study site located in a quarry on the Lincolnshire Limestone has been selected to examine the validity of the ‘dual porosity’ hypothesis and its application in models for the prediction of solute migration. An integrated approach has been adopted for the experimental programme, combining data obtained from both field and laboratory-scale investigations with mathematical modelling. The results of the first to stages of the experimental developments at the site are reported and the results are discussed in relation to he development of a full tracer test programme.
Fracture mapping has been conducted on the face and the floor of the quarry where the vertical fractures are seen to be discontinuous over depth. However, extensive horizontal bedding plane fissures are readily identifiable in the boreholes and represent the main paths for lateral flows. An extensive data collection programme has been conducted to characterize the hydraulic properties of these fissures, as well as the adjacent altered and unaltered matrix. Important results for future tracer testing were obtained from the hydraulic tests which suggest the strong possibility of non-Darcian flow in the fissures under pumping and tracer test conditions and the probability of strong spreading of solutes at injection wells under forced inflows. Preliminary tracer tests confirm the difficulty of employing laboratory defined diffusion coefficients as input data to ‘dual porosity’ models of local-scale transport.
The geology and hydrogeology of Sellafield: an overview
Authors: Chaplow Robert 
Published: November 2007

Abstract
Nirex is responsible for providing and managing a national facility for solid intermediate-level and low-level radioactive waste. Geological and hydrogeological investigations have been in progress at Sellafield in west Cumbria since 1989 aimed at determining whether or not the site is suitable for such a deep repository. Geological investigations have included the drilling of 20 deep boreholes with over 20000 metres of drilling, together with almost 2000 line kilometres of seismic surveys and over 8000 line kilometres of airborne geophysical surveys. Hydrogeological testing and groundwater sampling and testing have provided additional information on the ground conditions at the site.
The results from the investigations show that the Borrowdale Volcanic Group of rocks, the top surface of which is 400–600 m beneath the site at Sellafield, holds good promise as an eventual location for the repository. Further investigations are required before the suitability of the site can be confirmed. These additional investigations will include the construction of an underground rock-characterization facility for which Nirex applied for planning permission to construct in 1994.
The investigations carried out to date have defined the subsurface structure of the area and have defined a stratigraphic subdivision of the Borrowdale Volcanic Group. Groundwater flow within the volcanic rocks has been shown to be occurring through a limited number of fractures and preliminary work has been undertaken to characterize these hydrogeologically significant fractures. Hydrogeochemical studies have begun to characterize the groundwater types and preliminary results have indicated that the groundwaters at depth are saline with residence times in excess of tens of thousands of years.