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The conference was originally conceived as a way of bringing the best of current research activities to an audience spanning the minerals community as a whole, both academic and also industrial research and development. Plenary papers cover the following topics: The EU and its EIP on raw materials - securing Europe's future growth, by Drielsma J.; Minerals in mine wastes: resources, recycling, remediation, by Hudson-Edwards K., 2 refs.; Engineering minerals for performance applications - an industrial perspective, by Phipps J. Session topics are as follows: Sessions 1+2: Security of supply: critical metals and other commodities (14 abstracts); Sessions 3+4: Minerals processing/recycling (5 abstracts);.Session 5: Engineering mineral functionality; Sessions 6+7: Engineering mineral functionality (total 14 abstracts); Sessions 8+9: Radioactive waste management - engineered barrier and natural analogue systems (10 abstracts); Session 10: Carbon capture and storage (4 abstracts); Session 11: Biomining and bioremediation (5 abstracts); Session 12: Biomine realisation: fundamental and applied research; Session 13: Use of large-scale facilities in minerals sciences and industry; general session (4 abstracts); poster session (13 posters)., The conference was originally conceived as a way of bringing the best of current research activities to an audience spanning the minerals community as a whole, both academic and also industrial research and development. Plenary papers cover the following topics: The EU and its EIP on raw materials - securing Europe's future growth, by Drielsma J.; Minerals in mine wastes: resources, recycling, remediation, by Hudson-Edwards K., 2 refs.; Engineering minerals for performance applications - an industrial perspective, by Phipps J. Session topics are as follows: Sessions 1+2: Security of supply: critical metals and other commodities (14 abstracts); Sessions 3+4: Minerals processing/recycling (5 abstracts);.Session 5: Engineering mineral functionality; Sessions 6+7: Engineering mineral functionality (total 14 abstracts); Sessions 8+9: Radioactive waste management - engineered barrier and natural analogue systems (10 abstracts); Session 10: Carbon capture and storage (4 abstracts); Session 11: Biomining and bioremediation (5 abstracts); Session 12: Biomine realisation: fundamental and applied research; Session 13: Use of large-scale facilities in minerals sciences and industry; general session (4 abstracts); poster session (13 posters).

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Session Precambrian Geology, vol.42, n.5, info:eu-repo/semantics/nonPublished

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The Belait Formation comprises alternating sandstones, sand and clays in varying proportions and thickness and is believed to have been deposited as an isolated basin infilling oscillating between littoral and deltaic-paralic type. Ripples are occasionally encountered in this Formation. However, there is a lack of information on the kind of ripples present and the link between the ripples and the associated flow dynamics within the Belait Formation. This information is extremely useful for a better understanding of the formation of these sedimentary basins especially for the oil and gas industry. Therefore, the main objective of this study was to evaluate the ripple marks occurring in an outcrop belonging to this Formation. The specific objectives were to ascertain the origin of these marks, to estimate the principal flow directions and to link the characteristics of the ripple marks to the flow characteristics. Approximately 800 measurements of ripples were made at this outcrop along three vertical transects.Ripples are generally asymmetrical in cross section and the ripple indices are inconsistent throughout the outcrop. The ripple indices show temporal and spatial variations within and between strata. The majority of the ripples have sinuous in phase patterns. A few strata at the top of the outcrop exhibit linguoid patterns. Principal flow directions as assessed from the ripples were NE or SE. All strata have fine sand texture. The quartz grains are subrounded and do not exhibit any preferred orientation. Interstitial spaces are filled with iron-oxyhydroxides. Taking into consideration the mean particle size in each strata, the estimated mean flow velocity in a unidirectional sense would be about 0.3-0.4m/s under laminar flow conditions. Evidently, there has been no appreciable increase in this flow rate as there are no evidences of planar stratification in the field. The change in the flow direction is non-systematic from a temporal perspective. These changes ap

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Vertebrate hard parts are potentially a rich source of informatio about the biology of the extinct animals. However, established techniques for studying vertebrate fossils recover only a small part of this information and the techniques are also destructive, which severely limits their utility particularly with rare material. Recently, the use of conventional CT scanning has been used because non-destructive "serial sections" can now be produced rapidly and three-dimensional models reconstructed electronically. However, the resolution provided by most conventional CT scanners is insufficient to study histological features. Very recently, the advent of synchroton CT scanning has been used to visualize sublte texture differences with negligible absorption contrast.Here we present its use to systematically survey, document and reconstruct soft-tissue contacts such as arrested growth surfaces and Sharpey's fibres. Integral to this project is the fossils from the Gogo Formation in Western Australia as they preserve actual soft tissue structures. Recently small areas of muscle tissue were identified in the placoderm Eastmanosteus, which included blood vessels and nerve fibres (Trinajstic et al. 2007) and the preserved umbilical cord connecting the embryo of the ptyctodont Materpiscis to a yold sac (Long et al. 2008). New discoveries have revealed large areas of phosphatised muscle preserved beneath dermal plates in placoderm fishes. For the first time we can map the postcranial musculature in an extinct placoderm fish. In addition structures interpreted as the heart, liver and abdominal tract have been identified in palaeoniscoid fishes. The excellent 3D preservation in these fossils has provided proof of the synchrotron technique.

The CD and abstracts book include papers and summaries from four sessions. Topics include risk mitigation, borehole logging for structural mapping, gravity and magnetic data collection and interpretation, reflection seismics of South African precious metal deposits, TDEM data from the Lufilian arc, VTEM improvements and use of borehole radar. Other papers or summaries are: Diamond exploration with airship-borne gravity gradiometer, by Hatch D., p.19 (abstract only); Application of the vertical electrical resistivity and magnetic resonance sounding (VES and MRS) techniques for groundwater exploration, by Meyer R., p.20-21 + 38pp. on CD; Magnetotellurics, by van der Walt J., 37pp. text+slides on CD; Some practical aspects of mining-related seismicity, by Milev A., p.22 + 32pp. slides on CD; The application of high-resolution geophysics to in- mine problems, by van Schoor M., p.25 + 50pp. slides on CD; From the air, on the ground and down the borehole - cost-effective deployment of the geophysical tool box in mineral exploration, by Campbell G., p.25-26 (brief abstract only); and Where others waver - an ongoing study case from Gabon, west central Africa, by Eberle D., p.27-28 + 42pp. slides on CD., The CD and abstracts book include papers and summaries from four sessions. Topics include risk mitigation, borehole logging for structural mapping, gravity and magnetic data collection and interpretation, reflection seismics of South African precious metal deposits, TDEM data from the Lufilian arc, VTEM improvements and use of borehole radar. Other papers or summaries are: Diamond exploration with airship-borne gravity gradiometer, by Hatch D., p.19 (abstract only); Application of the vertical electrical resistivity and magnetic resonance sounding (VES and MRS) techniques for groundwater exploration, by Meyer R., p.20-21 + 38pp. on CD; Magnetotellurics, by van der Walt J., 37pp. text+slides on CD; Some practical aspects of mining-related seismicity, by Milev A., p.22 + 32pp. slides on CD; The application of high-resolution geophysics to in- mine problems, by van Schoor M., p.25 + 50pp. slides on CD; From the air, on the ground and down the borehole - cost-effective deployment of the geophysical tool box in mineral exploration, by Campbell G., p.25-26 (brief abstract only); and Where others waver - an ongoing study case from Gabon, west central Africa, by Eberle D., p.27-28 + 42pp. slides on CD.

The organisers' aim was that collectively the symposium presentations and papers should be of value in appreciating the limitations involved in mapping, boring, drilling, sampling and testing natural materials, and in making judgements about the representability of data in modelling the ground in Hong Kong. General topics include the importance of comprehensive rock and soil description in ground modelling, the implications for geotechnical engineering of weathering and erosion processes in rocks, the effect of discontinuities on the mass stability of tropically weathered rocks, and the incorrect use of empirically derived correlations and incorrect curve fitting in the analysis of geotechnical data. Papers whose titles refer specifically to Hong Kong are on the Hong Kong Geological Survey's work on the classification and distribution of rocks and superficial deposits in the area, the laboratory characterisation and geotechnical properties of soils, factors governing rock failure mechanisms, and advanced or special testing systems, such as the double-cell triaxial system, for the properties and behaviour of marine soils. The papers include illustrative maps, sections, photographs, tables and diagrams, many in colour, as well as lists of further references., The organisers' aim was that collectively the symposium presentations and papers should be of value in appreciating the limitations involved in mapping, boring, drilling, sampling and testing natural materials, and in making judgements about the representability of data in modelling the ground in Hong Kong. General topics include the importance of comprehensive rock and soil description in ground modelling, the implications for geotechnical engineering of weathering and erosion processes in rocks, the effect of discontinuities on the mass stability of tropically weathered rocks, and the incorrect use of empirically derived correlations and incorrect curve fitting in the analysis of geotechnical data. Papers whose titles refer specifically to Hong Kong are on the Hong Kong Geological Survey's work on the classification and distribution of rocks and superficial deposits in the area, the laboratory characterisation and geotechnical properties of soils, factors governing rock failure mechanisms, and advanced or special testing systems, such as the double-cell triaxial system, for the properties and behaviour of marine soils. The papers include illustrative maps, sections, photographs, tables and diagrams, many in colour, as well as lists of further references.

Geological studies were combined with laboratory measurements of thermal properties and heat-production rates to constrain a finite- element thermal model. Scenarios examined integrated structural variations in the crust with a range of chronological settings: the thermal regime was calculated before and after Eburnean thrust tectonism in the period 2130-2095 Ma, just before deposit formation. To satisfy the thermobarometric observations, the most probable mantle heat flow must have been 60 mW/m2, at least three times more than at present. The results also indicate that shallow anomalies of lateral heat flow reached 25 mW/m2 at the margins of each lithological unit, including the Ashanti belt; these are explicable mostly by lateral contrasts in thermal conductivity and could have been important for the mineralising events, as they would have favoured local circulation., Geological studies were combined with laboratory measurements of thermal properties and heat-production rates to constrain a finite- element thermal model. Scenarios examined integrated structural variations in the crust with a range of chronological settings: the thermal regime was calculated before and after Eburnean thrust tectonism in the period 2130-2095 Ma, just before deposit formation. To satisfy the thermobarometric observations, the most probable mantle heat flow must have been 60 mW/m2, at least three times more than at present. The results also indicate that shallow anomalies of lateral heat flow reached 25 mW/m2 at the margins of each lithological unit, including the Ashanti belt; these are explicable mostly by lateral contrasts in thermal conductivity and could have been important for the mineralising events, as they would have favoured local circulation.

A review and synthesis is presented of information relating to the variations in mineral deposits with time related to the Earth's cooling, changes in tectonic style, evolution of the atmosphere-hydrosphere- biosphere system, and types of sedimentary host rocks. A table summarises the main features of the deposit types discussed in the text, which include epigenetic gold deposits, volcanic-hosted massive sulphides, placer and palaeoplacer gold, iron oxide-copper-gold deposits, platinum- group elements in large layered intrusions, primary diamond deposits, uranium, iron, manganese, Mississippi Valley-type and sedex deposits. It is concluded that the distinctive, often unique, temporal patterns of deposit-type distributions reflect a complex interplay between formational and preservational processes that in turn resulted from changes in tectonic processes and environmental conditions in an evolving Earth. The decrease in crustal growth rate and change from thick, buoyant sub-continental lithospheric mantle led to progressive decoupling of formation from preservation, affecting patterns of orogenic, porphyry, epithermal, VHMS, placer, IOCG, PGE, diamond and probably sedex deposits. Sedimentary deposits of redox-sensitive metals were particularly affected by progressive oxidation of the atmosphere and related hydrospheric and biospheric changes, ending the formation of U placer, banded Fe and BIF- associated Mn carbonate and culminating in deposits such as MVT hosted by biogenic sedimentary rocks., A review and synthesis is presented of information relating to the variations in mineral deposits with time related to the Earth's cooling, changes in tectonic style, evolution of the atmosphere-hydrosphere- biosphere system, and types of sedimentary host rocks. A table summarises the main features of the deposit types discussed in the text, which include epigenetic gold deposits, volcanic-hosted massive sulphides, placer and palaeoplacer gold, iron oxide-copper-gold deposits, platinum- group elements in large layered intrusions, primary diamond deposits, uranium, iron, manganese, Mississippi Valley-type and sedex deposits. It is concluded that the distinctive, often unique, temporal patterns of deposit-type distributions reflect a complex interplay between formational and preservational processes that in turn resulted from changes in tectonic processes and environmental conditions in an evolving Earth. The decrease in crustal growth rate and change from thick, buoyant sub-continental lithospheric mantle led to progressive decoupling of formation from preservation, affecting patterns of orogenic, porphyry, epithermal, VHMS, placer, IOCG, PGE, diamond and probably sedex deposits. Sedimentary deposits of redox-sensitive metals were particularly affected by progressive oxidation of the atmosphere and related hydrospheric and biospheric changes, ending the formation of U placer, banded Fe and BIF- associated Mn carbonate and culminating in deposits such as MVT hosted by biogenic sedimentary rocks.

The aim of the meeting was both to highlight the importance of mineral deposits and to increase understanding of their links to Earth systems. The first two papers address the effects of meteorite impact, both in general and with reference to the Witwatersrand basin. A group of papers then considers the role of mineral deposits in constraining models of tectonic evolution on different scales, revealing that Archaean cratons are more richly endowed with metals than younger rocks, with the distinctive metal signature of each reflecting mantle heterogeneity, and that deposit types vary in time as a function of formation and preservation processes. Heat-flow constraints on the Ashanti gold belt and the plate-tectonic frameworks for giant gold deposits and for the Urals metallogenic province are discussed and other studies of particular aspects of early source rocks and conditions for ore genesis include: Terrane and basement discrimination in northern Britain using sulphur isotopes and mineralogy of ore deposits, by Lowry D., Boyce A.J., Fallick A.E., Stephens W.E. and Grassineau N.V., p.133-151, 80 refs., which compares four terranes; The terrestrial record of stable sulphur isotopes: a review of the implications for evolution of Earth's sulphur cycle, by Farquhar J. and Wing B.A., p.167-177, 43 refs.; Reactive iron enrichment in sediments deposited beneath euxinic bottom waters: constraints on supply by shelf recycling, by Raiswell R. and Anderson T.F., p.179-194, 98 refs., on a model derived from studies of modern basins such as the Black Sea and Cariaco basin; and Distinguishing biological from hydrothermal signatures via sulphur and carbon isotopes in Archaean mineralisations at 3.8 and 2.7 Ga, by Grassineau N.V., Appel P.W.U., Fowler C.M.R. and Nisbet E.G., p.195-212, 75 refs, a discussion of the Isua and Belingwe greenstone belts. Finally, deposit-forming sedimentary and igneous processes are addressed in two papers on diamond placers and porphyry Cu-Au-Mo deposi, The aim of the meeting was both to highlight the importance of mineral deposits and to increase understanding of their links to Earth systems. The first two papers address the effects of meteorite impact, both in general and with reference to the Witwatersrand basin. A group of papers then considers the role of mineral deposits in constraining models of tectonic evolution on different scales, revealing that Archaean cratons are more richly endowed with metals than younger rocks, with the distinctive metal signature of each reflecting mantle heterogeneity, and that deposit types vary in time as a function of formation and preservation processes. Heat-flow constraints on the Ashanti gold belt and the plate-tectonic frameworks for giant gold deposits and for the Urals metallogenic province are discussed and other studies of particular aspects of early source rocks and conditions for ore genesis include: Terrane and basement discrimination in northern Britain using sulphur isotopes and mineralogy of ore deposits, by Lowry D., Boyce A.J., Fallick A.E., Stephens W.E. and Grassineau N.V., p.133-151, 80 refs., which compares four terranes; The terrestrial record of stable sulphur isotopes: a review of the implications for evolution of Earth's sulphur cycle, by Farquhar J. and Wing B.A., p.167-177, 43 refs.; Reactive iron enrichment in sediments deposited beneath euxinic bottom waters: constraints on supply by shelf recycling, by Raiswell R. and Anderson T.F., p.179-194, 98 refs., on a model derived from studies of modern basins such as the Black Sea and Cariaco basin; and Distinguishing biological from hydrothermal signatures via sulphur and carbon isotopes in Archaean mineralisations at 3.8 and 2.7 Ga, by Grassineau N.V., Appel P.W.U., Fowler C.M.R. and Nisbet E.G., p.195-212, 75 refs, a discussion of the Isua and Belingwe greenstone belts. Finally, deposit-forming sedimentary and igneous processes are addressed in two papers on diamond placers and porphyry Cu-Au-Mo deposi

Over 160 impact structures are known worldwide, 30% of them buried beneath later sediments, and several more are discovered each year. About 25% have some form of associated economic resource and 12% are being or have been exploited. Progenetic deposits include iron ore at Ternovka in Russia, uranium at Carswell in Canada, and gold and uranium in the annular trough surrounding the Vredefort impact structure in South Africa, which has resulted in the preservation of the Witwatersrand ores. Syngenetic deposits include the occurrence of impact diamonds in several structures, notably Popigai in Siberia, and over 1 600 000 000 tonnes of Cu-Ni-PGE ores associated with the Sudbury structure in Ontario. Most epigenetic deposits have resulted from post-impact sedimentary activity within the structure or the trapping of migrating fluids such as the hydrocarbons at Red Wing Creek in North Dakota and Ames in Oklahoma., Over 160 impact structures are known worldwide, 30% of them buried beneath later sediments, and several more are discovered each year. About 25% have some form of associated economic resource and 12% are being or have been exploited. Progenetic deposits include iron ore at Ternovka in Russia, uranium at Carswell in Canada, and gold and uranium in the annular trough surrounding the Vredefort impact structure in South Africa, which has resulted in the preservation of the Witwatersrand ores. Syngenetic deposits include the occurrence of impact diamonds in several structures, notably Popigai in Siberia, and over 1 600 000 000 tonnes of Cu-Ni-PGE ores associated with the Sudbury structure in Ontario. Most epigenetic deposits have resulted from post-impact sedimentary activity within the structure or the trapping of migrating fluids such as the hydrocarbons at Red Wing Creek in North Dakota and Ames in Oklahoma.

The distribution of deposits containing more than 100 t Au is controlled by complex hydrothermal processes that operate within specific geodynamic settings. These controls can be unravelled by considering the mineralising fluids in the context of the source-migration-trap paradigm and tectonic setting. Gold in a subduction-related setting may have a mantle source while crustal sources are limited to hydrated rocks of bulk mafic composition that have been subjected to low-grade metamorphism. Gold-bearing fluids may be dominated by deep or shallow magma or may be multi-source; basinal fluids have a more limited potential. A geodynamic classification of crustal settings has three main categories: accretional collisional orogens; non-accretionary collisional orogens; and non-collisional orogens such as accretionary arc complexes, active continental margins and island arcs., The distribution of deposits containing more than 100 t Au is controlled by complex hydrothermal processes that operate within specific geodynamic settings. These controls can be unravelled by considering the mineralising fluids in the context of the source-migration-trap paradigm and tectonic setting. Gold in a subduction-related setting may have a mantle source while crustal sources are limited to hydrated rocks of bulk mafic composition that have been subjected to low-grade metamorphism. Gold-bearing fluids may be dominated by deep or shallow magma or may be multi-source; basinal fluids have a more limited potential. A geodynamic classification of crustal settings has three main categories: accretional collisional orogens; non-accretionary collisional orogens; and non-collisional orogens such as accretionary arc complexes, active continental margins and island arcs.

There are only two known mega-placers, defined as containing 50 000 000 carats or more with at least 95% gem quality: both are on the SW African coast fringing the Kaapvaal craton one associated with the Orange-Vaal dispersal and the other, to the south, of uncertain origin. The Kalahari craton-Orange River-SE African coast system is used as a model to illustrate the variables associated with diamond dispersal and trapping and the important factors needed to generate a vary large placer deposit. The four main groups of controls on development of a mega-placer are the craton, the drainage, the terminal environment and the timing. Cratons, being buoyant, tend to leak diamonds into surrounding basins, though orogens may return these as foreland basin fill. The craton's size, diamond-fertility and retention of successive kimberlites are significant in mega-placer development. Maximum potential recovery is achieved by efficient drainage with no major older rivers and the supply focused on a limited terminal area with sufficient energy to remove accompanying sediment. All these conditions should be near-contemporaneous., There are only two known mega-placers, defined as containing 50 000 000 carats or more with at least 95% gem quality: both are on the SW African coast fringing the Kaapvaal craton one associated with the Orange-Vaal dispersal and the other, to the south, of uncertain origin. The Kalahari craton-Orange River-SE African coast system is used as a model to illustrate the variables associated with diamond dispersal and trapping and the important factors needed to generate a vary large placer deposit. The four main groups of controls on development of a mega-placer are the craton, the drainage, the terminal environment and the timing. Cratons, being buoyant, tend to leak diamonds into surrounding basins, though orogens may return these as foreland basin fill. The craton's size, diamond-fertility and retention of successive kimberlites are significant in mega-placer development. Maximum potential recovery is achieved by efficient drainage with no major older rivers and the supply focused on a limited terminal area with sufficient energy to remove accompanying sediment. All these conditions should be near-contemporaneous.

A multi-technique study of samples from auriferous units and their hanging- and footwalls, from locations spanning the preserved stratigraphic and geographic extent of the Central Rand Group, has led to the development of a regional model for the present distribution of the gold. More than 80% of gold clearly showed hydrothermal textural characteristics but electron microprobe analysis showed that remobilisation and homogenisation can only have occurred over small distances, with grains 1 cm or 1 mm apart having different chemistries. The data thus support the modified palaeoplacer model. As more than 70% of gold overgrows brittle fractures in late chlorite and quartz, the timing of the final crystallisation was late. Cataclasis of pyrite is widely reported but is not spatially correlated with larger tectonic features. The only reasonable candidate to have caused widespread and severe brittle deformation of consistent and uniform timing in the paragenetic sequence was the Vredefort impact, dated to 2023+/-4 Ma., A multi-technique study of samples from auriferous units and their hanging- and footwalls, from locations spanning the preserved stratigraphic and geographic extent of the Central Rand Group, has led to the development of a regional model for the present distribution of the gold. More than 80% of gold clearly showed hydrothermal textural characteristics but electron microprobe analysis showed that remobilisation and homogenisation can only have occurred over small distances, with grains 1 cm or 1 mm apart having different chemistries. The data thus support the modified palaeoplacer model. As more than 70% of gold overgrows brittle fractures in late chlorite and quartz, the timing of the final crystallisation was late. Cataclasis of pyrite is widely reported but is not spatially correlated with larger tectonic features. The only reasonable candidate to have caused widespread and severe brittle deformation of consistent and uniform timing in the paragenetic sequence was the Vredefort impact, dated to 2023+/-4 Ma.

The mineral inventories of 12 Archaean cratons are compared quantitively with mineral distributions across the larger Phanerozoic continents of Gondwana, Africa and South America to compare and contrast the changing metallogenic fingerprints of the Earth's continental lithosphere. Some cratons have Au, Cu, Pb and Zn signatures that fit with simple accretionary models whereas others are remarkably enriched in siderophile elements such as Ni, Cr and PGE or relatively enriched in Sn, W and U/Th. The numbers of deposits in different mineral groups are tabulated for the Kaapvaal, Limpopo, Zimbabwe, Congo, Tanzania, Leo-Man and Requibath cratons., The mineral inventories of 12 Archaean cratons are compared quantitively with mineral distributions across the larger Phanerozoic continents of Gondwana, Africa and South America to compare and contrast the changing metallogenic fingerprints of the Earth's continental lithosphere. Some cratons have Au, Cu, Pb and Zn signatures that fit with simple accretionary models whereas others are remarkably enriched in siderophile elements such as Ni, Cr and PGE or relatively enriched in Sn, W and U/Th. The numbers of deposits in different mineral groups are tabulated for the Kaapvaal, Limpopo, Zimbabwe, Congo, Tanzania, Leo-Man and Requibath cratons.

The major metallogenic province of the Urals contains world-class Cr, VMS Cu-Zn, orogenic Au and Fe-oxide skarn deposits. The Main Urals Fault separates a western slope that represents a deformed passive continental margin from an eastern oceanic slope that combines collided and welded magmatic arcs, sutured ocean basins and microcontinents. The tectonic evolution of the orogenic belt is better defined by mineral deposits: major Cr and medium-sized VMS deposits in the Sakmara ophiolitic zone, major VMS deposits in the Magnitogorsk magmatic arc zone, porphyry and Kiruna-type deposits in the eastern ocean-arc complexes, and fault-controlled Au deposits related to syn-collisional granitoids., The major metallogenic province of the Urals contains world-class Cr, VMS Cu-Zn, orogenic Au and Fe-oxide skarn deposits. The Main Urals Fault separates a western slope that represents a deformed passive continental margin from an eastern oceanic slope that combines collided and welded magmatic arcs, sutured ocean basins and microcontinents. The tectonic evolution of the orogenic belt is better defined by mineral deposits: major Cr and medium-sized VMS deposits in the Sakmara ophiolitic zone, major VMS deposits in the Magnitogorsk magmatic arc zone, porphyry and Kiruna-type deposits in the eastern ocean-arc complexes, and fault-controlled Au deposits related to syn-collisional granitoids.

Geological and LA-ICP-MS microanalytical data from the calcalkaline volcanic complex hosting the Bajo de la Alumbrera Cu-Au deposit are integrated with fluid-chemical data from Grasberg, Bingham, Elatsite, Butte and two barren New Mexican porphyries to re-assess the processes likely to control size, grade and metal ratios. Total metal content is probably determined, to a first order, by the dimension of the magmatic fluid source. Final concentration is proportional to the degree of fluid focusing, initial concentration in the fluid and precipitation efficiency. The data consistently indicate that the bulk Au/Cu ratio of a deposit is similar to the average ratio of the incoming ore brine although selective precipitation of different Cu/Fe sulphides at varying temperatures may be responsible for Au/Cu zoning in some deposits., Geological and LA-ICP-MS microanalytical data from the calcalkaline volcanic complex hosting the Bajo de la Alumbrera Cu-Au deposit are integrated with fluid-chemical data from Grasberg, Bingham, Elatsite, Butte and two barren New Mexican porphyries to re-assess the processes likely to control size, grade and metal ratios. Total metal content is probably determined, to a first order, by the dimension of the magmatic fluid source. Final concentration is proportional to the degree of fluid focusing, initial concentration in the fluid and precipitation efficiency. The data consistently indicate that the bulk Au/Cu ratio of a deposit is similar to the average ratio of the incoming ore brine although selective precipitation of different Cu/Fe sulphides at varying temperatures may be responsible for Au/Cu zoning in some deposits.

Note: This file is extremely large. Prepared for the Geological Society of America Rocky Mountain Section meeting in Cedar City, Utah, May 7-9, 2002

Papers and discussion are presented as seven chapters: Why an EU initiative on mining waste? by Marmo L., p.1-4; Monitoring inspection and reporting on tips in relation to their construction, by Walton G. and Cobb A., p.5-17, 7 refs.; The chemical and physical impacts of recent mine tailings dam failures on river systems - key issues for sustainable catchment management in former and present metal mining areas, by Macklin M.G., Brewer P.A., Coulthard T.J., Turner J.N., Bird G. and Hudson-Edwards K., p.18-24, 13 refs.; The UK's interest in mining waste, and how best to influence the commission's proposals, by Knapman D., p.25-33; The proposed EU mine waste directive - a researcher's view from the drafting table, by Younger P.L., p.34-42, 11 refs; The proposed directive on the management of mining waste, by Cambridge M., p.43-45, 2 refs.; and Should there be a new directive and, if so, what should it cover? Discussion led by Tom Simpson, p.46-50., Papers and discussion are presented as seven chapters: Why an EU initiative on mining waste? by Marmo L., p.1-4; Monitoring inspection and reporting on tips in relation to their construction, by Walton G. and Cobb A., p.5-17, 7 refs.; The chemical and physical impacts of recent mine tailings dam failures on river systems - key issues for sustainable catchment management in former and present metal mining areas, by Macklin M.G., Brewer P.A., Coulthard T.J., Turner J.N., Bird G. and Hudson-Edwards K., p.18-24, 13 refs.; The UK's interest in mining waste, and how best to influence the commission's proposals, by Knapman D., p.25-33; The proposed EU mine waste directive - a researcher's view from the drafting table, by Younger P.L., p.34-42, 11 refs; The proposed directive on the management of mining waste, by Cambridge M., p.43-45, 2 refs.; and Should there be a new directive and, if so, what should it cover? Discussion led by Tom Simpson, p.46-50.

Extended abstracts, many with maps, diagrams or brief lists of further references, are presented on: the Curraghinalt gold deposit, County Tyrone (2 papers); international barite production and deposits; the Parys Mountain polymetallic deposit, Anglesey (3 papers); the Glendinning turbidite-hosted As-Sb-Au deposit, Southern Uplands; crustal contamination and Ni-Cu mineralisation, Arthrath mafic intrusion, NE Scotland; Mike Gallagher's contribution to understanding metallogenesis; exploration data from the Dalradian of Glen Shee; stratabound deposits and development of the Scandinavian Caledonides (4 papers); gold at Calliachar and Urlar Burn, Scotland; microchemical characterisation of Scottish alluvial gold; platinum group metals in the Shetland ophiolites; precious and strategic metals in the central Wales Pb-Zn district; uranium in the Devonian of northern Scotland; caldera-related base metals in the English Lake District; isotopic constraints on deposition of Aberfeldy barite/sulphides, central Highlands; controls on Cononish gold-silver deposit, SW Highlands; geochemistry of the British Caledonides; stream sediments from Lagalochan Ag-Au-Cu prospect, western Scotland; concentration of platinum group elements; hydrothermal exhalations and the emergence of life; ternary projections in mineralogy and petrology; base metals in Ordovician rocks, County Waterford; gold exploration and modelling in the Caledonides; isotope analysis, Clontibret gold-arsenopyrite-pyrite deposit, Ireland; geochemistry of UK shelf sediments; relationship of source and drainage geochemistry, British Caledonides; skarn deposits, British Isles; Silurian arc-related series of the central Urals; and a possible dispersion halo in the Ben Eagach Schists., Extended abstracts, many with maps, diagrams or brief lists of further references, are presented on: the Curraghinalt gold deposit, County Tyrone (2 papers); international barite production and deposits; the Parys Mountain polymetallic deposit, Anglesey (3 papers); the Glendinning turbidite-hosted As-Sb-Au deposit, Southern Uplands; crustal contamination and Ni-Cu mineralisation, Arthrath mafic intrusion, NE Scotland; Mike Gallagher's contribution to understanding metallogenesis; exploration data from the Dalradian of Glen Shee; stratabound deposits and development of the Scandinavian Caledonides (4 papers); gold at Calliachar and Urlar Burn, Scotland; microchemical characterisation of Scottish alluvial gold; platinum group metals in the Shetland ophiolites; precious and strategic metals in the central Wales Pb-Zn district; uranium in the Devonian of northern Scotland; caldera-related base metals in the English Lake District; isotopic constraints on deposition of Aberfeldy barite/sulphides, central Highlands; controls on Cononish gold-silver deposit, SW Highlands; geochemistry of the British Caledonides; stream sediments from Lagalochan Ag-Au-Cu prospect, western Scotland; concentration of platinum group elements; hydrothermal exhalations and the emergence of life; ternary projections in mineralogy and petrology; base metals in Ordovician rocks, County Waterford; gold exploration and modelling in the Caledonides; isotope analysis, Clontibret gold-arsenopyrite-pyrite deposit, Ireland; geochemistry of UK shelf sediments; relationship of source and drainage geochemistry, British Caledonides; skarn deposits, British Isles; Silurian arc-related series of the central Urals; and a possible dispersion halo in the Ben Eagach Schists.

An extended abstract and a paper are presented: Geology and exploration of the Yandal belt, Western Australia, by Phillips N., 1p.; and Discovery of the Bronzewing gold mine, by Eshuys E., Herbison I., Phillips N. and Wright J., 15pp., 8 refs. Less than ten years ago the Yandal greenstone belt appeared devoid of significant gold deposits, but the discovery of Bronzewing, Jundee, Mount McClure, Darlot and Goudis has changed perceptions dramatically. The extensive and in places deep cover that handicapped early prospectors, and the recent recognition that the belt is part of the Norseman-Wiluna belt, make it likely that further deposits will be found. Bronzewing is one of the largest gold deposits discovered in Australia for several decades, with resources estimated from undercut assays at 20 200 000 tonnes ore grading 4.7 g/t Au. It was discovered during a regional rotary air-blast drilling programme after conceptual geological studies had identified favourable areas of the Yandal belt. Like many other Archaean greenstone gold deposits it is a structurally controlled quartz vein hosted by a greenschist-facies basalt succession with strong alteration around the mine area and sulphide and mica alteration immediately adjacent to gold mineralisation. There are a number of distinct ore shoots of variable geometry, some of which continue below 400 m. The current resource is constrained within a volume with dimensions of about 1.5 x 0.5 x 0.5 km., An extended abstract and a paper are presented: Geology and exploration of the Yandal belt, Western Australia, by Phillips N., 1p.; and Discovery of the Bronzewing gold mine, by Eshuys E., Herbison I., Phillips N. and Wright J., 15pp., 8 refs. Less than ten years ago the Yandal greenstone belt appeared devoid of significant gold deposits, but the discovery of Bronzewing, Jundee, Mount McClure, Darlot and Goudis has changed perceptions dramatically. The extensive and in places deep cover that handicapped early prospectors, and the recent recognition that the belt is part of the Norseman-Wiluna belt, make it likely that further deposits will be found. Bronzewing is one of the largest gold deposits discovered in Australia for several decades, with resources estimated from undercut assays at 20 200 000 tonnes ore grading 4.7 g/t Au. It was discovered during a regional rotary air-blast drilling programme after conceptual geological studies had identified favourable areas of the Yandal belt. Like many other Archaean greenstone gold deposits it is a structurally controlled quartz vein hosted by a greenschist-facies basalt succession with strong alteration around the mine area and sulphide and mica alteration immediately adjacent to gold mineralisation. There are a number of distinct ore shoots of variable geometry, some of which continue below 400 m. The current resource is constrained within a volume with dimensions of about 1.5 x 0.5 x 0.5 km.

The chapters cover a wide spectrum of activities and range from exploration models, exploration drilling and sampling, ore reserves, to mine design, financial evaluation, mine sampling and grade control, and finally to reconciliation between estimated and mill recovered grades. The resources considered include precious and base metals, industrial minerals, coal, clay and aggregates. Deposits described come from all over the world and include examples from Australia, Chile, Western USA, Bangladesh and Zimbabwe, as well as examples from the United Kingdom. Many chapters consider the application of geostatistics and discussions highlight inherent problems., The chapters cover a wide spectrum of activities and range from exploration models, exploration drilling and sampling, ore reserves, to mine design, financial evaluation, mine sampling and grade control, and finally to reconciliation between estimated and mill recovered grades. The resources considered include precious and base metals, industrial minerals, coal, clay and aggregates. Deposits described come from all over the world and include examples from Australia, Chile, Western USA, Bangladesh and Zimbabwe, as well as examples from the United Kingdom. Many chapters consider the application of geostatistics and discussions highlight inherent problems.

The volume is divided into the following 11 sessions: General 1 (4 papers); Mining 1 (2 papers); Metallurgy 1 (3 papers); Geology - exploration (4 papers); Metallurgy 2 (4 papers); Mining 2 (3 papers); Metallurgy 3 (4 papers); Mining 3 (4 papers); Metallurgy 4 (3 papers); Geology (3 papers); and General 2 (3 papers)., The volume is divided into the following 11 sessions: General 1 (4 papers); Mining 1 (2 papers); Metallurgy 1 (3 papers); Geology - exploration (4 papers); Metallurgy 2 (4 papers); Mining 2 (3 papers); Metallurgy 3 (4 papers); Mining 3 (4 papers); Metallurgy 4 (3 papers); Geology (3 papers); and General 2 (3 papers).

The topics covered in this volume achieve a balance between reports of extensive experience in certain aspects of placers, and those discussing new elements of exploration and exploitation technology and commercial assessment. Placer mining is often linked to small scale mining which in aggregate can contribute significantly to the national economics and industrial bases of many countries in the SE Asian and Pacific regions; it is hoped this symposium will help in transferring Australian technical expertise. Resources covered include gold, marine aggregates, platinum, heavy mineral sand, diamond, and tin., The topics covered in this volume achieve a balance between reports of extensive experience in certain aspects of placers, and those discussing new elements of exploration and exploitation technology and commercial assessment. Placer mining is often linked to small scale mining which in aggregate can contribute significantly to the national economics and industrial bases of many countries in the SE Asian and Pacific regions; it is hoped this symposium will help in transferring Australian technical expertise. Resources covered include gold, marine aggregates, platinum, heavy mineral sand, diamond, and tin.