A new approach to mapping large volcanic provinces

We present a method currently being applied to the Afar Region of the African Rift to rapidly map large volcanic areas. At BGS we apply an integrated approach involving remote sensing and three-dimensional image analysis of topography and surface rock chemistry based on mineral maps generated from false colour Landsat and ASTER imagery within an immersive visualisation suite. Subsequently these digital images and first pass geological interpretations are transferred to a field data tablet, enabling digital data capture in the field. Alternatively, hard copy printouts are generated of the various data layers. Ground truthing in the field involves targeted spot mapping, transects and detailed mapping of poor resolution areas. This approach is proving to be particularly successful in producing a subdivision of basaltic lava flows based on surface features, morphology of flow lobes and emplacement styles, where chemostratigraphic applications fail to identify individual eruption units. Within this structure, further applications such as chemostratigraphy may be utilised in order to elucidate process orientated research of a temporally related series of eruptions. The success of this technique is particularly significant when working in areas which are difficult to access, and may be applied in the future within environmentally or logistically challenging regions