Baseline geochemical mapping in the UK : the G-BASE programme

National geochemical mapping in the UK is undertaken by the BGS as part of the Geochemical Baseline Survey of the Environment (G-BASE) Programme. The programme began in the early 1970’s in the North of Scotland and will provide a comprehensive high resolution baseline geochemical database for the whole country by the year 2012. The ongoing development and inclusion of state-of-the-art analytical and computing techniques and rigorous quality control over the past 25 years have been fundamental in creating consistent geochemical maps which reflect geological, geomorphological and landuse parameters

Review of agricultural pollution in the Caribbean with particular emphasis on small island developing states

Recent studies have attributed the degradation of coastal living resources in the Caribbean to the potential impacts of agricultural pollution. Physical features controlling the delivery, retention and dispersal of pollutants throughout the region are discussed. Information relating to four types of agricultural pollution is presented and assessed: soil erosion leading to siltation, nutrient enrichment, pesticide contamination and agro-industrial pollution. The results of this review have enabled gaps in knowledge to be identified. Areas prone to soil erosion and the reasons for their susceptibility are known. There is a paucity of baseline data on turbidity and on the concentration of nutrients and pesticides in the coastal zone. The increase in the use of agricultural fertilisers and pesticides over the last 20 years suggests a concomitant rise in their loads to coastal waters. Few studies have made direct links between agricultural pollution, reduction in coastal water quality or clarity, and the degradation of coastal living resources

Review of agricultural pollution in the Caribbean with particular emphasis on small island developing states

Recent studies have attributed the degradation of coastal living resources in the Caribbean to the potential impacts of agricultural pollution. Physical features controlling the delivery, retention and dispersal of pollutants throughout the region are discussed. Information relating to four types of agricultural pollution is presented and assessed: soil erosion leading to siltation, nutrient enrichment, pesticide contamination and agro-industrial pollution. The results of this review have enabled gaps in knowledge to be identified. Areas prone to soil erosion and the reasons for their susceptibility are known. There is a paucity of baseline data on turbidity and on the concentration of nutrients and pesticides in the coastal zone. The increase in the use of agricultural fertilisers and pesticides over the last 20 years suggests a concomitant rise in their loads to coastal waters. Few studies have made direct links between agricultural pollution, reduction in coastal water quality or clarity, and the degradation of coastal living resources

The role of geochemical baselines in the assessment of land quality

In the light of recent European and UK government legislation there is a need to identify and quantify the potential hazard of contaminated land. Previous attempts to define ‘safe levels’ of Potentially Harmful Elements and Species (PHES) have proved to be less than satisfactory. For example, when the Council of European Communities (CEC) guideline for nickel was applied to regional geochemical baseline data in Finland, extensive areas of the north-west of the country were designated as contaminated it spite of their being little evidence of harm to the indigenous population or environment. In the UK, many areas containing high concentrations (i.e. above the Inter-governmental Committee on Redevelopment of Contaminated Land trigger values) of PHES have been identified. There is a clear role for geochemical baselines in assessing and revising these guidelines, and in the assessment of their potential economic impact

Estudio geológico de la Cordillera Occidental del Norte del Perú - [Boletín D 10]

El estudio analiza la geología de la Cordillera Occidental del Perú, desde la latitud cercana a Lima hasta la frontera con el Ecuador. Se evalúa la cadena montañosa comprendiendo rocas de edad mesozoica así como la parte occidental de la Cordillera Andina. El área de estudio se encuentra dentro de latitudes tropicales, con influencia de vientos alisios del Sureste y contexto árido (desde el nivel del mar hasta los 1500 m.s.n.m ) y con zoneamiento climático vertical (desde 2500 a 4500 m.s.n.m.) controlado por la altitud. Se analiza la geomorfología constatando las elevaciones concordantes y un patrón de drenaje maduro, observado por McLaughlin en la llamada Superficie Puna y la evaluación de las rocas volcánicas y sedimentarias. La estratigrafía revela la presencia del Mesozoico y Cenozoico en Los Andes Septentrionales y Centrales del Perú, detallándose los depósitos de las distintas formaciones. En cuanto a la geología estructural se identifican las diversas estructuras del sistema montañoso. Se calculan e interpretan las Edades radiométricas. Se aporta la geoquímica aplicable a las rocas intrusivas y volcánicas del Perú Central. Se realizó un mapeo de reconocimiento geológico y levantamiento geoquímico del Sector Norte de la Cordillera Occidental, evaluando el potencial minero y delineando depósitos desconocidos con importancia económica, en la provincia polimetálica andina (Norte de Chile y Bolivia hasta el Ecuador). El reconocimiento geoquímico abarcó un área de 25000 km², entre las latitudes 4° 30’ S y 7° 15’ S y longitudes 78° 0’ y 80° 0’. Se reporta la mineralización conocida en el área que incluye los depósitos de Michiquillay, Turmalina y el Distrito de Hualgayoc. Se destacan tres anomalías principales de las cuales dos exhiben cursos de dispersión geoquímica considerablemente más largas que Michiquillay. Esta investigación forma parte del Programa de Cooperación Técnica entre los gobiernos Británico y del Perú y los trabajos de campo y gabinete tuvieron desarrollo entre los años 1963 y 1972. Incluye bibliografía

Evolution of the Western Amazon Lowland Relief: impact of Andean foreland dynamics

The congruency in the depositional origin and age of the uppermost sedimentary strata forming non-flooded rainforest ground (terra firme) in the western and central Amazon lowlands is a much debated subject. Here we conclude from the study of remote sensing imagery that active Andean foreland dynamics have played a major role in the evolution of the Plio-Pleistocene fluvial landscape in the western Amazon. Foreland dynamics have resulted in a terra firme composed of late Tertiary alluvium and younger alluvial terraces and plains. In Peru, thermoluminescence and I4C dating show local aggradation of this younger alluvium between 180 and 30 ka. The documented high age heterogeneity of the terra firme has implications for considerations of the biogeography of the Amazon forest