CAPER 2000. Meeting of the Committee for Air Pollution Effects Research (CAPER). Book of abstracts

[摘要] A series of four trial airborne environmental and geological surveys was flown by the Geological Survey of Finland (GTK) in collaboration with the British Geological Survey (BGS) in June 1999; the trials were co-sponsored by the Department of the Environment, Transport and the Regions and the Environment Agency. The main objective of these surveys was to test the efficiency of the GTK airborne electromagnetic (EM) system in the mapping of potential pollution problems in the UK environment. Gamma spectrometric and magnetometric measurements were also collected to see to what extent these techniques provide complementary information. The EM data are particularly encouraging and have identified anomalies which may relate to subsurface pollution. The data have identified conductive zones both on the ��local�� scale (i.e. possibly emanating from domestic landfills) through to regional scale features up to many kilometres in length. The information obtained in relation to spoil tip drainage is of particular note. The data have provided a wealth of information on ��point source�� anomalies (requiring ground truth information) and diffuse sources that may be connected with groundwater extraction. At two sites (Trent Valley and Langar) the EM technique appears to have met the challenge of detecting conductive targets in a conductive host. Many other features of the data will take time to assess. The radiometric data indicate features of land fill and colliery spoil sites and allow comparison to be made rapidly with the EM data to define the lateral spread of conductive pore fluids beyond the site itself. They can also be used to map site-specific contamination where radioactive elements are present. The radiometric data also give direct indications of solid and drift geology and soil type, providing additional detail to that shown on geological maps (soil maps are not available for much of the UK). The magnetic data have suggested the presence of significant volumes of metallic debris in the Langar landfill sites. This may be significant in terms of the leachates derived and the compaction (through time) of the contrasting fill materials. Compared with the EM and radiometric techniques, the applications of magnetics in environmental studies are rather limited, but such data is worthwhile collecting in view of the marginal additional costs involved.

[发布机构] NERC/Centre for Ecology & Hydrology

[学科分类] 大气科学