Accessible Resource Base Research Articles

Organisational intentions and responses: presenting the risk of Lyme disease to countryside users

With more people working or recreating in the countryside, there is a need for land-based organisations to manage potential risks. We explore the role of risk communication as a tool for preventing staff or the wider publics contracting Lyme disease. Through interviews with representatives of land-based organisations and content analysis of information they provide, we focus on the relationship between organisational attitudes towards Lyme disease and the information they provide. While there is an appetite for a consistent approach to communicating about Lyme disease, we found that there is currently no clear agreement over the level of information that should be communicated, how and to whom. Moreover, how organisations approach risk communication in practice is variable. A potential solution would be an accessible resource base which provides accurate and consistent information that can be tailored to different audiences.

Speaking Out and Doing Justice: It's No Longer a Secret but What are the Churches Doing about Overcoming Violence against Women?

Some concerns raised by gender violence have been taken up by churches and individuals within them over the last ten years or so, but now the World Council of Churches has set up a project to work specifically on Overcoming Violence Against Women. The project has a three-fold task aimed at enabling constructive engagement with the issue of gender violence: (1) to support and encourage the churches' (2) to develop a network of concerned theologians; (3) to establish an accessible resource base. The prevalence of violence against women in all parts of society, including churches and Christian communities, raises theological questions. Some areas of language, doctrine and the interpretation of Scripture need to be examined and perhaps reconsidered, to provide theologies consistent with churches as communities of safety, respect and justice for women.

Geothermal investigations in Slovenia

The paper presents the methodology and the results of geothermal investigations, based on seventy-two boreholes in the territory of the Republic of Slovenia. The data of fundamental geothermal quantities: formation temperature, thermal conductivity, and radiogenic heat production of rocks as well as surface heat flow density are stored in a computerized data base. Their synthesis is given in the map of formation temperatures at 1000 m depth and in the map of surface heat flow density. In both maps the thermal difference between the Pannonian basin in the eastern and the Dinarides in the western part of Slovenia is clearly expressed. However, in the boundary area between these two tectonic units, for a distance of about 100 km in SW-NE direction, elevated horizontal gradients of formation temperature as well as heat flow density are evident. A small positive thermal anomaly in the Ljubljana depression is conspicuous. The low-temperature geothermal resources in Slovenia such as thermal springs and thermal water from boreholes, are estimated to have a flow rate of 1120 kg/s, corresponding to the ideal total heat production of 144 MWt. In the geothermally promising areas amounting to 3200 km2 the rate of accessible resource base (ARB) down to the depth of 3 km has been assessed to about 8.5 x 1020 J.

Geothermal energy in Canada

Since 1973 an effort has been made to identify and assess geothermal resources within Canada. Although the task is far from complete, two areas have been examined in some detail: the recent volcanic complex of Meager Mountain, British Columbia, and the Western Platform in British Columbia, Alberta and Saskatchewan. It has been found that there are substantial resources associated with both, but of different character. At Meager Mountain high-temperature water will probably eventually be used for the generation of electrical power, whereas the low- to medium-temperature resources of the Basin are suitable for space heating and direct use. The useful accessible resource base in the waters of the Western Platform is very large, and reserves, estimated as 1% of the resource base are an order of magnitude greater than the thermal equivalent of Canadian oil reserves. In eastern Canada, where conventional energy supplies are more expensive, prospects for geothermal resources are not generally favourable, except in small areas. Development of geothermal resources in Canada is hindered by the absence of an established industry and, except in the Province of British Columbia, of legislation for the control of exploration and development of geothermal resources.

Geothermal resources of the United Kingdom

Geothermal prospects in the UK are represented by low enthalpy resources in deep sedimentary basins and 'Hot Dry Rock' (HDR) resources in radiothermal granites, and possibly in deep basement rocks where they are overlain by thick low conductivity sediments. The low enthalpy resources are in Permo-Triassic sandstones at temperatures of more than 40°C. Four deep exploration wells have been drilled to investigate the potential of these sedimentary aquifers. The main HDR resource potential is associated with major granite batholiths in southwest and northern England where temperatures are predicted to be 200°C at about 5.4 and 6 km respectively. The HDR potential is being investigated by the Camborne School of Mines at their test site in Cornwall where three boreholes have been drilled to depths of between 2 and 2.5 km. The Hot Dry Rock Accessible Resource Base at temperatures of more than 100°C and depths of less than 7 km is 36 X 10 21 joules (equivalent to 130 × 10 4 million tons of coal). The low enthalpy Geothermal Resource of the Permo-Triassic sandstones at temperatures of more than 40°C is 200 × 10 l8 joules (equivalent to about 8000 million tons of coal). If only a small fraction of these resources could be developed, it would be significant in terms of the UK’s energy balance.

Effect of device reliability on memory reliability : Jonathan A. Humphry. IEEE Trans. Reliab.R-29 (5) 416 (December 1980)

A consistent, agreed-upon terminology is prerequisite for geothermal resource assessment. Accordingly, we propose a logical, sequential subdivision of the “geothermal resource base”, accepting its definition as all the thermal energy in the earth's crust under a given area, measured from mean annual temperature. That part of the resource base which is shallow enough to be tapped by production drilling is termed the “accessible resource base”, and it in turn is divided into “useful” and “residual” components. The useful component (i.e. the thermal energy that could reasonably be extracted at costs competitive with other forms of energy at some specified future time) is termed the “geothermal resource”. This in turn is divided into “economic” and “subeconomic” components, based on conditions existing at the time of assessment.In the format of a McKelvey diagram, this logic defines the vertical axis (degree of economic feasibility). The horizontal axis (degree of geologic assurance) contains “identified” and “undiscovered” components. “Reserve” is then designated as the identified economic resource. All categories should be expressed in units of thermal energy, with resource and reserve figures calculated at wellhead, prior to the inevitable large losses inherent in any practical thermal use or in conversion to electricity.Methods for assessing geothermal resources can be grouped into 4 classes: (a) surface thermal flux, (b) volume, (c) planar fracture and (d) magmatic heat budget. The volume method appears to be most useful because (1) it is applicable to virtually any geologic environment, (2) the required parameters can in Sprinciple be measured or estimated, (3) the inevitable errors are in part compensated and (4) the major uncertainties (recoverability and resupply) are amenable to resolution in the foreseeable future.The major weakness in all the methods rests in the estimation of how much of the accessible resource base can be extracted at some time in the future. In a manner similar to mineral and fuel assessment, this recoverability is expressed as a “recovery factor”. For an ideally permeable hot-water system, the recovery factor may be as much as 50% and seems to be independent of temperature. It must decrease as effective porosity (φe) decreases, but the relation between the two is little more than a guess. On the other hand, for favorable systems like Larderello that produce steam by a mechanism of intergranular vaporization, the recovery factor is probably around 15–20%, decreasing to zero at an effective porosity of zero. According to the anlysis of Bodvarsson (1974), it increases with decreasing reservoir temperature, and as pointed out by Nathenson (1975a) is limited at low temperatures by the need to have sufficient reservoir pressure for extraction and use.The extent to which a geothermal reservoir can be resupplied with heat during “industrial” times of 10–100 yr can be evaluated using simple analytical models. The results, combined with gravity and levelling data of Hunt (1977) for Wairakei and Isherwood (1977) for The Geysers, confirm earlier conclusions by Ramey (1970) and Nathenson (1975a) that resupply to reservoirs producing only steam can be neglected, and the conclusion of Nathenson (1975a) that it may be significant for hot-water systems of high natural discharge.Major subjects that demand continuing investigation include: 1.1. Determination of recovery factors as functions of temperature and effective porosity, particularly for hot-water systems.2.2. Evaluation of fluid recharge and heat resupply by repetitive gravity, levelling and underground temperature surveys in producing geothermal fields.3.3. Analysis of the extent to which a recovery factor can be enhanced by stimulation and by use of confined circulation loops.

Methods for regional assessment of geothermal resources

A consistent, agreed-upon terminology is prerequisite for geothermal resource assessment. Accordingly, we propose a logical, sequential subdivision of the “geothermal resource base”, accepting its definition as all the thermal energy in the earth's crust under a given area, measured from mean annual temperature. That part of the resource base which is shallow enough to be tapped by production drilling is termed the “accessible resource base”, and it in turn is divided into “useful” and “residual” components. The useful component (i.e. the thermal energy that could reasonably be extracted at costs competitive with other forms of energy at some specified future time) is termed the “geothermal resource”. This in turn is divided into “economic” and “subeconomic” components, based on conditions existing at the time of assessment. In the format of a McKelvey diagram, this logic defines the vertical axis (degree of economic feasibility). The horizontal axis (degree of geologic assurance) contains “identified” and “undiscovered” components. “Reserve” is then designated as the identified economic resource. All categories should be expressed in units of thermal energy, with resource and reserve figures calculated at wellhead, prior to the inevitable large losses inherent in any practical thermal use or in conversion to electricity. Methods for assessing geothermal resources can be grouped into 4 classes: (a) surface thermal flux, (b) volume, (c) planar fracture and (d) magmatic heat budget. The volume method appears to be most useful because (1) it is applicable to virtually any geologic environment, (2) the required parameters can in Sprinciple be measured or estimated, (3) the inevitable errors are in part compensated and (4) the major uncertainties (recoverability and resupply) are amenable to resolution in the foreseeable future. The major weakness in all the methods rests in the estimation of how much of the accessible resource base can be extracted at some time in the future. In a manner similar to mineral and fuel assessment, this recoverability is expressed as a “recovery factor”. For an ideally permeable hot-water system, the recovery factor may be as much as 50% and seems to be independent of temperature. It must decrease as effective porosity ( φ e ) decreases, but the relation between the two is little more than a guess. On the other hand, for favorable systems like Larderello that produce steam by a mechanism of intergranular vaporization, the recovery factor is probably around 15–20%, decreasing to zero at an effective porosity of zero. According to the anlysis of Bodvarsson (1974), it increases with decreasing reservoir temperature, and as pointed out by Nathenson (1975 a) is limited at low temperatures by the need to have sufficient reservoir pressure for extraction and use. The extent to which a geothermal reservoir can be resupplied with heat during “industrial” times of 10–100 yr can be evaluated using simple analytical models. The results, combined with gravity and levelling data of Hunt (1977) for Wairakei and Isherwood (1977) for The Geysers, confirm earlier conclusions by Ramey (1970) and Nathenson (1975 a) that resupply to reservoirs producing only steam can be neglected, and the conclusion of Nathenson (1975 a) that it may be significant for hot-water systems of high natural discharge. Major subjects that demand continuing investigation include: 1. 1. Determination of recovery factors as functions of temperature and effective porosity, particularly for hot-water systems. 2. 2. Evaluation of fluid recharge and heat resupply by repetitive gravity, levelling and underground temperature surveys in producing geothermal fields. 3. 3. Analysis of the extent to which a recovery factor can be enhanced by stimulation and by use of confined circulation loops.

Coastal and marine information dissemination programs

Abstract Coastal and marine information dissemination programs are discussed in terms of their importance and effectiveness in helping shape decisions affecting coastal zone resources. Information is defined as the communication of knowledge through useful and meaningful collections of data. Elements that contribute to the effectiveness of an information program include: (1) inputs from an accessible resource base, e.g., by direct contact with project leaders in various areas of research, (2) timeliness of data, (3) professionally trained communicators, (4) a variety of products tailored to meet specific needs of each target audience, (5) a distribution network capable of identifying appropriate audiences, and (6) a reliable and systematic feedback mechanism.