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Our recent geological survey of the basement of central and northern Madagascar allowed us to re-evaluate the evolution of this part of the East Africa–Antarctica Orogen (EAAO). Five crustal domains are recognized, characterized by distinctive lithologies and histories of sedimentation, magmatism, deformation and metamorphism, and separated by tectonic and/or unconformable contacts. Four consist largely of Archaean metamorphic rocks (Antongil, Masora and Antananarivo Cratons, Tsaratanana Complex). The fifth (Bemarivo Belt) comprises Proterozoic meta-igneous rocks. The older rocks were intruded by plutonic suites at c. 1000 Ma, 820– 760 Ma, 630–595 Ma and 560–520 Ma. The evolution of the four Archaean domains and their boundaries remains contentious, with two end-member interpretations evaluated: (1) all five crustal domains are separate tectonic elements, juxtaposed along Neoproterozoic sutures and (2) the four Archaean domains are segments of an older Archaean craton, which was sutured against the Bemarivo Belt in the Neoproterozoic. Rodinia fragmented during the early Neoproterozoic with intracratonic rifts that sometimes developed into oceanic basins. Subsequent Mid- Neoproterozoic collision of smaller cratonic blocks was followed by renewed extension and magmatism. The global ‘Terminal Pan-African’ event (560–490 Ma) finally stitched together the Mid-Neoproterozoic cratons to form Gondwana.

The response of individuals from three different populations of three-spined sticklebacks to acute and chronic periods of hypoxia (4.4 kPa DO, 2.2 mg l-1) were tested using measures of whole-body (WB) cortisol, glucose and lactate. Although there was no evidence of a neuroendocrine stress response to acute hypoxia, fish from the population least likely to experience hypoxia in their native habitat had the largest response to low oxygen, with significant evidence of anaerobic glycolysis after two hours of hypoxia. However, there was no measurable effect of a more prolonged period (seven days) of hypoxia on any of the fish in this study, suggesting that they acclimated to this low level of oxygen over time. Between-population differences in the analytes tested were observed in the control fish of the acute hypoxia trial, which had been in the laboratory for 16 days. However, these differences were not apparent among the control fish in the chronic exposure groups that had been held in the laboratory for 23 days suggesting that these site-specific trends in physiological status were acclimatory. Overall, the results of this study suggest that local environmental conditions may shape sticklebacks’ general physiological profile as well as influencing their response to hypoxia.

The British Geological Survey has undertaken a programme of research on landslide hazard mapping under support from the Department for International Development. The aim of the studies has been to develop a generic approach to landslide hazard modelling that can be applied and adapted in developing countries worldwide. The overall goal of the research is to prevent or minimise the loss of life and damage to property, infrastructure and livelihoods caused by landslides. To this end, case studies in four countries have been used to develop a rapid, inexpensive method for the production of regional landslide hazard maps. This report presents specific results and findings from the Slovakian study area in the Javorniky Mountains. The report is aimed at people and organisations in Slovakiathat are concerned with, or affected by, landslides. It discusses local issues that affect the development of landslide hazard preparedness strategies in individual countries. The accompanying map is a first attempt at mapping the regional landslide hazard in this part of Slovakia. It can be improved through additional local knowledge and the incorporation of more data on possible controlling factors, for example. Ultimately, the success of the project can only be judged by the take up, use and development of the hazard map in Slovakia.

The British Geological Survey has undertaken a programme of research on landslide hazard mapping under support from the Department for International Development. The aim of the studies has been to develop a generic approach to landslide hazard modelling that can be applied and adapted in developing countries worldwide. The overall goal of the research is to prevent or minimise the loss of life and damage to property, infrastructure and livelihoods caused by landslides. To this end, case studies in four countries have been used to develop a rapid, inexpensive method for the production of regional landslide hazard maps. This report presents specific results and findings from the Jamaican study area in the Rio Minho.The report is aimed at people and organisations in Jamaica that are concerned with, or affected by, landslides. It discusses local issues that affect the development of landslide hazard preparedness strategies in individual countries. The accompanying map is a first attempt at mapping the regional landslide hazard in this part of Jamaica. It can be improved through additional local knowledge and the incorporation of more data on possible controlling factors, for example. Ultimately, the success of the project can only be judged by the take up, use and development of the hazard map in Jamaica.

A landslide hazard probability map can help planners (1) prepare for, and/or mitigate against, the effects of landsliding on communities and infrastructure, and (2) avoid or minimise the risks associated with new developments. The aims of the project were to establish, by means of studies in a few test areas, a generic method by which remote sensing and data analysis using a geographic information system (GIS) could provide a provisional landslide hazard zonation map. The provision of basic hazard information is an underpinning theme of the United Nations International Decade for Natural Disaster Reduction (IDNDR). It is an essential requirement for disaster preparedness and mitigation planning. This report forms part of BGS project 92/7 (R5554) ‘Rapid assessment of landslip hazards’ carried out under the ODA/BGS Technology Development and Research Programme as part of the British Government’s provision of aid to developing countries. It provides a detailed technical account of work undertaken in a test area in the highlands of Papua New Guinea (PNG) in collaboration with the Geological Survey Division. The study represents a demonstration of a methodology that is applicable to many developing countries. The underlying principle is that relationships between past landsliding events, interpreted from remote sensing, and factors such as the geology, relief, soils etc. provide the basis for modelling where future landslides are most likely to occur. This is achieved using a GIS by ‘weighting’ each class of each variable (e.g. each lithology ‘class’ of the variable ‘geology’) according to the proportion of landslides occurring within it compared to the regional average. Combinations of variables, produced by summing the weights in individual classes, provide ‘models’ of landslide probability. The approach is empirical but has the advantage of potentially being able to provide regional scale hazard maps over large areas quickly and cheaply; this cannot be achieved using

A landslide hazard probability map can help planners (1) prepare for, and/or mitigate against, the effects of landsliding on communities and infrastructure, and (2) avoid or minimise the risks associated with new developments. The aims of the project were to establish, by means of studies in a few test areas, a generic method by which remote sensing and data analysis using a geographic information system (GIS) could provide a provisional landslide hazard zonation map. The provision of basic hazard information is an underpinning theme of the UN’s International Decade for Natural Disaster Reduction (IDNDR). It is an essential requirement for disaster preparedness and mitigation planning. This report forms part of BGS project 92/7 (R5554) ‘Rapid assessment of landslip hazards’ Carried out under the ODA/BGS Technology Development and Research Programme as part of the British Government’s provision of aid to developing countries. It provides a detailed technical account of work undertaken in a test area in Viti Levu in collaboration with Fiji Mineral Resources Department. The study represents a demonstration of a methodology that is applicable to many developing countries. The underlying principle is that relationships between past landsliding events, interpreted from remote sensing, and factors such as the geology, relief, soils etc provide the basis for modelling where future landslides are most likely to occur. This is achieved using a GIS by ‘weighting’ each class of each variable (e.g. each lithology ‘class’ of the variable ‘geology’) according to the proportion of landslides occurring within it compared to the regional average. Combinations of variables, produced by summing the weights in individual classes, provide ‘models’ of landslide probability. The approach is empirical but has the advantage of potentially being able to provide regional scale hazard maps over large areas quickly and cheaply; this is unlikely to be achieved using conventional ground-based geot

Except for a sequence of Carboniferous and Cretaceous sandstones in the west, the sheet area is occupied by Upper Proterozoic metasediments and calc-alkaline volcanics/subvolcanics with thrust ophiolite nappes/melanges, syn- to late-tectonic granitoids, and post-tectonic mafic-ultramafic and potassic calc-alkaline granitoid intrusions. Proterozoic marbles are mined in the north-west. Talc is worked where a talc/ankerite ophiolitic reef outcrops north of Wadi al Allaqi. Nearby altered dacitic subvolcanics at Umm Qurayyat contain pyrite gold mineralisation and an abandoned gold mine is associated with chlorite-rich intermediate volcanics, schists and related tuffs. Gold was formerly mined from similar rocks in the south (near Wadi Abu Fas) and east (two mines, Jabal Shashubah area, while copper has been mined from undifferentiated schists and tuffs in the north, near Wadi Haymur. Podiform chromite occurs where serpentinites outcrop in the centre of the map area, north of Wadi Murrah., Except for a sequence of Carboniferous and Cretaceous sandstones in the west, the sheet area is occupied by Upper Proterozoic metasediments and calc-alkaline volcanics/subvolcanics with thrust ophiolite nappes/melanges, syn- to late-tectonic granitoids, and post-tectonic mafic-ultramafic and potassic calc-alkaline granitoid intrusions. Proterozoic marbles are mined in the north-west. Talc is worked where a talc/ankerite ophiolitic reef outcrops north of Wadi al Allaqi. Nearby altered dacitic subvolcanics at Umm Qurayyat contain pyrite gold mineralisation and an abandoned gold mine is associated with chlorite-rich intermediate volcanics, schists and related tuffs. Gold was formerly mined from similar rocks in the south (near Wadi Abu Fas) and east (two mines, Jabal Shashubah area, while copper has been mined from undifferentiated schists and tuffs in the north, near Wadi Haymur. Podiform chromite occurs where serpentinites outcrop in the centre of the map area, north of Wadi Murrah.

The geology and stratigraphy of the area are outlined. Mineral deposits include manganese at Mutun and in the Murcielago district and iron ore at Mutun, Cerro Rojo and Cerro Colorado. Previous export potential is thought unlikely to be realised in the near future but the deposits could form the basis of a local steel industry. Other minerals include semi-precious stones, notably amethyst (which are worked by the military), limestone, sand and gravel. A geochemical survey indicated zinc anomalies which possibly result from carbonate-hosted mineralisation although no evidence of this was found in mapping., The geology and stratigraphy of the area are outlined. Mineral deposits include manganese at Mutun and in the Murcielago district and iron ore at Mutun, Cerro Rojo and Cerro Colorado. Previous export potential is thought unlikely to be realised in the near future but the deposits could form the basis of a local steel industry. Other minerals include semi-precious stones, notably amethyst (which are worked by the military), limestone, sand and gravel. A geochemical survey indicated zinc anomalies which possibly result from carbonate-hosted mineralisation although no evidence of this was found in mapping.

The stratigraphy and orogenic history of the Bolivian Precambrian rocks are discussed in seven chapters: Introduction; The metamorphic basement; The San Ignacio orogeny; The Sunsas orogenic cycle; The Brasiliano orogenic cycle; Proterozoic crustal evolution; and Phanerozoic (post Brasiliano). There then follows a chapter on the mineral resources of the region. Perhaps the most significant discovery is the Ascension de Guarayos tin field. A second major discovery is the Rincon del Tigre igneous complex with its associated primary copper and extensive high grade secondary nickel mineralisation., The stratigraphy and orogenic history of the Bolivian Precambrian rocks are discussed in seven chapters: Introduction; The metamorphic basement; The San Ignacio orogeny; The Sunsas orogenic cycle; The Brasiliano orogenic cycle; Proterozoic crustal evolution; and Phanerozoic (post Brasiliano). There then follows a chapter on the mineral resources of the region. Perhaps the most significant discovery is the Ascension de Guarayos tin field. A second major discovery is the Rincon del Tigre igneous complex with its associated primary copper and extensive high grade secondary nickel mineralisation.