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Real-time kinematic (RTK) and fast-static GPS offer accurate and efficient positioning strategies yet are rarely implemented for the use of deformation monitoring, typically giving way to long observation static GPS campaigns. These methods afford accuracies of better than a few centimetres, with observation periods of a matter of seconds to a few minutes. This makes them ideally suited to the detection of volcanic ground deformation, an environment in which the RTK system has not previously been applied but may fundamentally allow reduced time for potentially hazardous field observations particularly vital in crisis situations.

Classical GPS deformation surveys are conducted in continuous or repeated static mode which incur time, cost and effort constraints, and consequently tend to produce networks consisting of fewer points. The RTK and fast-static techniques, however, lend themselves ideally to the monitoring of dense array networks in localised deforming environments.

On Mount Etna, a dense network of traversing points on an actively deforming area were established to assess the use of RTK GPS for deformation monitoring, and to determine the structure and short-term deformation of the upper southern flank. This flank is of particular interest, being characterised as an area undergoing deformation due to preferential dyke propagation and flank instability.

Throughout the period of this study no rifting events occurred. However, results show coherent patterns of displacements. The observed horizontal and vertical displacements generally suggest inflation of a deep source followed by a shallow magma source inflation. Superimposed by summit dispacements due to changes in the magma column and gravity-related movements at the summit and adjacent to the caldera cliff edge. These magma and gravity-related stresses collectively enhance the mobility of the eastern sector of the edifice.

This research has shown that these techniques have the potential to measure rapidly evolving deformation in a fast and efficient manner, as well as detect smaller ongoing displacements. This makes them widely applicable in the field of volcanic ground deformation research.