bluuebunny/crossref_metadata_2025_split huggingface dataset:
Applied geological maps for planning and development: a review of examples from England and Wales, 1983 to 1996
Authors: Smith A. , Ellison R. A. 
Published: November 2007

Abstract
The former Department of the Environment has commissioned 35 applied geological mapping studies dealing with land-use planning in a range of geological and planning environments. These were carried out in England and Wales between 1983 and 1996. Using geological maps as a base these studies have developed two types of applied geological maps: thematic maps dealing with particular topics and summary maps bringing together many of the earth science factors relevant to planners and developers. The recommendations made by Geomorphological Services Limited (GSL) in 1985 in a previous review of these studies are summarized. The output, type and range of information, and its potential users are compared. Each study is assessed, with respect to the GSL recommendations, in terms of its content and usefulness, based in part on how it has been received by users. The main types of summary and thematic maps are described and guidance given on their content and presentation. The importance of maps in providing the key interface between earth scientists and planners is discussed, in particular the significance of map scale, use of colour and accuracy of the geological lines. Good practise is illustrated by reference to examples.
Long-term changes in the quality of polluted minewater discharges from abandoned underground coal workings in Scotland
Authors: Wood S. C. , Younger P. L. , Robins N. S. 
Published: November 2007

Abstract
Long-term trends of changes in the quality of water discharging from abandoned coal mines have been studied for 32 long-established discharges in the Midland Valley of Scotland. Six discharges have been studied in greater detail, providing insights into discharge quality evolution over more than a century. It has been found that minewater pollution is most severe in the first few decades after a discharge begins (the ‘first flush’), and that even the largest systems settle down to a lower level of pollution (particularly in terms of iron concentration) within 40 years. Long-term iron concentrations of less than 30 mg/1 are typical, and many are less than 10 mg/1. Low pH values (which might justify the over-used term ‘acid mine drainage’) do not generally persist, due to the rapid buffering of localized acidic waters by carbonates (both natural carbonates, and those introduced as rock powder for fire precautions during mining). This is corroborated by alkalinity concentrations, which tend to be highest in the early years of a discharge. While the pyrite content of the worked sequence strongly influences initial water quality (in terms of pH, iron and sulphate) during the ‘first flush’, there appears to be no correlation between long-term iron concentrations of discharges and pyrite content of local strata. Rather, higher levels are found in any sequence where there is scope for fluctuations of the water table in worked ground near to the discharge. A scientific approach to minewater remediation should allow for active treatment of discharges for the first decade or two, followed by long-term passive treatment after asymptotic pollutant concentrations are attained.
The use of shallow seismic techniques to characterize sub-surface Quaternary deposits: the example of Porth Neigwl (Hells Mouth Bay), Gwynedd, N. Wales
Authors: Brabham P. J. , McDonald R. J. , McCarroll D. 
Published: November 2007

Abstract

Porth Neigwl is a 6 km wide, drift-filled embayment, located on the Llyn Peninsula of northwest Wales, UK. The embayment is surrounded by hills formed of Lower Palaeozoic Rocks. Infilling the embayment is a 17 km
2
area of thick Quaternary deposits which are well exposed in the sea-cliff. These deposits have been studied intensely over the past century. However, previous workers have made little reference to the total extent or architecture of the Quaternary deposits that lie below present sea level and nothing is known about the rockhead geometry. A programme of high-resolution shallow seismic surveys are described, including 3 km of refraction and 1 km of shallow reflection profiling. Refraction results show that the Quaternary drift cover is variable in composition and thickness with a maximum thickness of 80 ± 8 m. However, results indicate that rockhead within the embayment lies consistently at an elevation of around - 32 m OD. The spatial distribution of refractor velocities is discussed. High-resolution shallow reflection surveys identify three major Quaternary sequences below present sea-level that are consistent across the area. This study demonstrates that combined seismic refraction and reflection studies are very useful in the rapid analysis of Quaternary stratigraphy and spatial depth to rockhead variations in areas of thick drift.
Geophysical investigation of proposed sites for artificial recharge in Northern Oman
Authors: Young M. E. , Al-Touqy Nasser , Khatim El , Adam Osman Abdullah 
Published: November 2007

Abstract
Sites in the interior of the Sultanate of Oman have been considered for the construction of recharge dams for temporarily impounding flood flows from the Northern Oman Mountains. Impounded water would be discharged under control to infiltrate into downstream aquifers. Four geophysical methods were applied to characterization of the spreading ground downstream of these sites and to guide drilling of test bores.
The main aquifers occur in permeable zones at the base of the alluvium and in the upper, weathered, bedrock. The alluvium is variably cemented and clay rich, and behaves as a confining layer between the shallow, unconsolidated surface infiltration zone and the aquifer.
The thickness of the upper unconsolidated layer of boulders and gravels was most accurately mapped with seismic refraction or vertical electrical sounding (VES). These methods were slow to apply in the arid, bouldery ground conditions and surveying was in places constrained by the wadi walls. Gravity survey, with control provided by VES, was a rapid method of profiling the total thickness of alluvium and weathered zone overlying the denser and more resistive unweathered ophiolite bedrock. VES was usefully supplemented by simultaneously measured induced polarization (IP) soundings which respond to the distribution of clay minerals.
Transient electromagnetic sounding (TEM) proved to be the most rapid method of survey as no ground contact was required. Alluvial thickness was interpreted by resistivity-depth modelling of TEM data and was most reliable over low-resistivity argillaceous mudstone or shale bedrock.
Ground penetrating radar survey to detect scour holes beneath the A525 highway at Nant-y-Garth Pass, Wales: a case history
Authors: Nichol D. , Reynolds J. M. 
Published: November 2007

Abstract
At Nant-y-Garth Pass, the A525 Wrexham to Ruthin Road is susceptible to undermining due to the scouring action of an adjacent fast-flowing stream. Concealed scour cavities were suspected following manual probing but the full threat posed to the integrity of the carriageway and to the safety of road users remained uncertain. Ground penetrating radar was used along a 350 m stretch of the highway to investigate the number and extent of scour holes beneath the carriageway. The survey identified extensive subsurface voiding with distinct anomalies associated with shallow cavities measuring up to 9 m long by 0.2 m high and extending as far as the centre of the road. More subdued radar features were interpreted as scoured pockets where fine-grained debris had been washed out and the remaining material had been disturbed and loosened. The results provided a basis for prioritizing countermeasures designed to repair the highway foundations and ensure the public safety.
Some geotechnical properties of the Claygate ‘Beds’ and Bagshot ‘Beds’ of south Essex
Authors: Northmore K. J. , Bell F. G. , Culshaw M. G. 
Published: November 2007

Abstract
The Claygate Beds and Bagshot Beds are the uppermost formations of Eocene age in south Essex, the former resting on the London Clay. The Claygate Beds consist primarily of silts and clays with subordinate sands, whilst sands are more common in the Bagshot Beds. The paper describes the geotechnical properties of these two sedimentary units. The results form part of a larger study of the engineering geology of south Essex.
The sands, particularly in the Bagshot Beds, are fine grained. All the sands are uniformly sorted and negatively skewed. Quartz is the principal minerals in these beds and in the fine material, mica, montmorillonite, kaolinite and chlorite figure in that order of relative abundance.
The geotechnical properties of the silts and clays of both formations are generally similar. However, the plasticity of the Claygate Beds tends to decrease somewhat from the lower to the upper division and the range of plasticity is greatest in the upper division. This may be due to the greater variation in quartz content and montmorillonite content in the latter division than in the two others. The clays in both formations tend to have normal activity whilst that of the silts is both normal and active.
The values of the undrained shear strength parameters, especially in the sandy material, are influenced by the amount of cement present, and the degree of interlocking of grains and the degree of compaction. The undrained shear strength of the silts and clays suggests that they range from soft to very stiff.
Discussion of ‘Influence of rainfall intensity and duration on slope stability in unsaturated soils’ by C. W. W. Ng & Q. Shi (Quarterly Journal of Engineering Geology, 31, 105–114)
Authors: McDougall J. , Ng C. W. W. , Shi Q. 
Published: November 2007

J. McDougall writes: The authors have presented a numerical study of the influence of rainfall infiltration on unsaturated slope stability. This type of approach can provide insights into the process of infiltration and has potential as a predictive tool but its usefulness is dependent on a realistic representation of the actual groundwater conditions. One area of difficulty, which can undermine the simulation exercise, is the interpretation of boundary flows.
In the case presented, the authors state that vertical boundaries FG and HI in Fig. 3 have prescribed hydraulic heads and boundary GH is impermeable. Infiltration due to rainfall is applied to boundary FI. It is, however, unclear whether this is applied over the entire exposed upper surface or some subsection of it. Since the vertical boundary heads are prescribed, any rise in main ground- water table due to applied rainfall, particularly if it is applied over the entire exposed surface, would be constrained by these boundary conditions. Are the authors able to comment on this and their conclusion that the main water table is not significantly affected by the different rainfall events considered?
The adjustment of a hydraulic regime to a prescribed boundary flow is something which may be usefully explored using an unsaturated flow model. Figure 5, which presumably reports the hydraulic conditions at the end of the 24-hour infiltration period, shows recurvate suction profiles at section C-C. Are these an indication of an advancing wetting front (especially in the case of the higher rainfall intensity) and not, as
Characterization of weathered volcanic rocks in Hong Kong
Authors: Irfan T. Y. 
Published: November 2007

Abstract

The mineralogical and fabric characteristics of weathered volcanic rocks, which are widespread in Hong Kong, are poorly documented. Consequently, the significant variations commonly observed, even at the same locality, in engineering properties and
in situ
behaviour of these rocks and the resulting soils cannot be adequately related to their basic mineralogical and fabric characteristics. A model for weathering of volcanic rocks, particularly those of pyroclastic origin, is presented in this paper. Modifications, similar to those recently proposed for granites by Irfan, are proposed to the material and mass weathering schemes commonly adopted in Hong Kong for the characterization of weathered volcanic rocks in engineering use. The appropriateness of various proposed petrographic and chemical weathering indices to generally fine-grained volcanic rocks is examined. A number of modifications are proposed to the standard soil preparation and testing methods for the soils formed from tropical weathering of volcanic rocks in order to obtain meaningful and more repeatable results.
A note on the estimation of permeability of granular soils
Authors: Trenter N. A. 
Published: November 2007

Abstract

Three methods are frequently adopted to measure the permeability of granular soils: determinations made on the basis of the soil's particle size distribution; on the results of
in situ
rising or falling head tests; and on the results of
in situ
pumping tests. The paper presents the results of permeability tests made using these three methods on granular soils during investigations for the construction of the Nigg Bay fabrication yard, Cromarty Firth. Of the methods based on particle size distribution, the one due to Masch & Denny was found to give results closest to the pumping test values. Permeabilities calculated using Hazen's rule were significantly higher than the pumping test results, while those calculated from the results of
in situ
falling head tests were significantly lower. On the basis of the results presented, there would appear to be a case for the adoption of a method such as Masch & Denny's for permeability estimation of granular soils.
Environmental hazards of unplanned urbanization of mountainous terrains: a case study of a Himalayan town
Authors: Anbalagan R. 
Published: November 2007

Abstract
Unplanned and non-systematic construction activities including road and building have been a major cause of environmental degradation in hilly terrains. Ill-conceived human urbanization over preciptous and critically stable hill slopes developed on geologically weak rock formations has often contributed to the instability of the slopes. The paper deals with impacts of human encroachment on the fragile ecological balance of Nainital, a famous hill resort of the Kamaun Himalaya, and discusses a scheme of mitigation measures to prevent further degradation of the environmental stability of the region.
Time Prediction of a Rock Fall in the Carnic Alps
Authors: Glawe U. , Zika P. , Zvelebil J. , Moser M. , Rybar J. 
Published: November 2007

Abstract
Based on an extensive field study and on the long-term monitoring of the kinematics of a toppling rock tower standing on a slope edge, a forecast of the time of its failure is presented. This is derived from a consideration of both present static equilibrium of the rock block including its kinematics and phenomenological characteristics and also the stage of disintegration of the block as part of the processes leading to rock fall.
Reversal shear box test for Hong Kong saprolitic soils
Authors: Au S. W. C. 
Published: November 2007

Abstract
The problem of material variability is a major difficulty in the determination of shear strength parameters for Hong Kong saprolitic soils. To obtain the parameters for slope design through direct shear testing, single samples can be used to overcome the problem if the ‘reversal’ shear box is employed. Such a method is explored and discussed in this Technical Note.
Abandoned mineworkings in chalk: approaches for appraisal and evaluation
Authors: Smith G. J. , Rosenbaum M. S. 
Published: November 2007

Abstract
An outline scheme is proposed for the appraisal of stability of abandoned mine workings in chalk, comprising a preliminary study, a practical appraisal and an evaluation. Those factors which define the pre-mining geological context are identified and their interaction discussed. A conceptual model for the potential deterioration of a mine is presented in terms of the processes which might occur. Outcomes, leading to some form of surface collapse, will depend on a measure of continuity of the various different constituent processes. Geographical information systems (GIS) are used for the evaluation. Their application is of particular benefit where an engineering classification scheme needs to be established.
Building stone: the geological dimension
Authors: Jefferson D. P. 
Published: November 2007

Abstract
Although the location, planning and operation of building stone quarries is similar in many respects to other industrial minerals, the scale of the operation and the methods used for stone extraction result in significant differences. Restoration and conservation techniques have rarely taken very much account of the petrology of the material to which they were applied. This is now changing. The complex chemical, mineralogical and biological changes involved in the weathering of stone demand a contribution from a multi-disciplinary team working on our cultural property.
The influence of granular calcareous particles on the residual shear strength of Fuller's Earth Clay
Authors: Hawkins A. B. , McDonald C. 
Published: November 2007

Abstract
Decalcification is proposed as a cause of the continued movement observed in many natural and engineered slopes in calcareous mudrock formations. It is deemed that such movement may potentially occur as granular calcareous particles, which otherwise maintain high residual shear strengths, are leached from shear surfaces within slipped masses, changing the mode of residual shear from transitional to sliding. Measurements of the residual shear strengths of 42 natural samples taken through the Fuller's Earth succession near Bath over a range of effective normal stresses emphasize the curved nature of many failure envelopes. The results demonstrate that the threshold between the two modes of shear occurs at approximately 25% calcite content. Fuller's Earth Clay with more than 25% calcite content is thus prone to significant decreases in residual shear strength upon partial or total decalcification.
Groundwater resources, their development and management in the UK: an historical perspective
Authors: Downing R. A. 
Published: November 2007

Abstract
The Water Act of 1945 can be considered to mark the beginning of modern quantitative hydrogeology in the UK. It introduced a period of some 20 years during which the assessment of resources was the dominant issue as groundwater was developed to meet the increasing post-war demands.
The significant effect that groundwater abstraction had on river flows was one of the reasons for the Water Resources Act of 1963. This legislation made regional groundwater management, with the river basin as the basic unit, a practical objective. From 1974, the degradation of groundwater quality and the risk of pollution increasingly became the main issue.
Groundwater resources of England and Wales provide 350f public water supplies. About 300f the infiltration to the main aquifers of the Mesozoic and Cenozoic is abstracted. The use of groundwater has increased by 80ince 1948 when data first became available.
Groundwater is now seen as a regional resource developed within the sophisticated water resource systems that are necessary for effective river basin management. Development must consider all demands on an aquifer including not only water supply but environmental aspects such as maintaining river flows and wetland environments.
Enfield-Haringey artificial recharge scheme
Authors: Baxter K. M. , O'Shea M. J. 
Published: November 2007

Artificial recharge was carried out experimentally in north London by the Water Resources Board and the Metropolitan Water Board between 1953 and 1970(Boniface 1959). These trials were successful, although only small volumes of water were recharged. Research by Thames Water Authority continued between 1975 and 1984 at a larger scale in the north London area (Flavin & Hawnt 1979; Flavin & Joseph 1983).
Thames Water Utilities drilled and tested 14 new production boreholes for the Enfield-Haringey Scheme along the course of the New River in north London (Fig. l, opposite). These new boreholes, together with nine existing sites, are designed to increase the strategic groundwater resources of north London by 90 Ml/d by artificially recharging the Chalk and Thanet Sands aquifer beneath London (O'Shea 1994).
During an average year, demand for water is often lower than that available from the Coppermills Water Treatment Works and between 10 and 20 M1/d of this excess fully treated water can be gravity recharged to the aquifer. This will be by low-rate, trickle recharge ensuring that the volume of water stored in the aquifer is sufficient to sustain a prolonged drought abstraction for up to 200 days. When demand for water is high, as in drought conditions, groundwater can be pumped from the aquifer, using the same boreholes, directly into the New River which acts as an aqueduct taking the water back to Coppermills, via the East Reservoir at Stoke Newington for treatment and supply. The scheme will be used strategically in times of
Topples on underdip slopes in the Highwood Pass, Alberta, Canada
Authors: Cruden D. M. , Hu Xian-Qin 
Published: November 2007

Abstract
Sixteen topples up to 15 m thick are exposed on underdip slopes in the Highwood Pass, Alberta. Topping modes are controlled by ratios of joint spacings to bedding thicknesses (block rations), rock strenght and topography, Block flexure topples occur where block ratios are less than 2, while block topples form where block ratios are larger than 2. multiple block topples develop sliding surfaces which may fracture thin beds rather than follow discontinuities. Chevron topples are retrogressive, simple block topples whose rupture surfaces coincide with hinge surfaces which may also develop into sliding surfaces. Chevron topples form on slopes over 35° and are typically less than 5 m thick. The development of sliding surfaces during block toppling may allow the displaced masses to become slides.
Undulatory extinction of quartz in some British granites in relation to age and potential reactivity
Authors: Graham West 
Published: November 2007

The undulatory extinction of quartz has become important in engineering geology because of its supposed indication of an alkali-silica reactive aggregate. In an earlier paper (West 1991) it was suggested that, for granites from a single orogenic region, the undulatory extinction angle of the quartz in the rock may be proportional to the age of the rock. The paper showed that this was true for granitic rocks. The paper showed that this was true for granitic rocks from the Chilean orogenic belt (de Hills & Corvalan 1964) and went on to suggest that it would be worthwhile to undertake a study of the undulatory extinction angle of quartz in British granites. This study has now been carried out by research at Leicester University, working on a project sponsored by TRL, the full results of which have been reported elsewhere (Smith & Dunham 1992). This Technical Note discusses two aspects of these results, namely undulatory extinction angel in relation to geological age and potential reactivity.
Undulatory extinction
There are two methods of measuring undulatory extinction on the ordinary flat stage of a popalarizing microscope. The first is that used by De Hills & Corvalan (1994) and is simply tha angle between the first appearance and last disappearance of the extinction shadow in the quartz grain. The second is that proposed by Dolar&Mantuani (1983) which, in addition, involves measuring the first and the last positions of maximum extinction. The two methods are:

De Hills & Corvalan

Appearance of first extinction shadow
A