Application of a geophysical monitoring system on the tidal and salt exposed embankments in the Humber Estuary, UK

摘要

A Geophysical Monitoring System (GMS) has been designed as a new instrument for monitoring of fluvial flood control dikes in the Czech Republic. Having used the GMS to define the hot spots of an existing embankment system, detailed investigation, maintenance and renewal efforts can be concentrated in a cost-effective way on the critical parts of the embankments. But there then raised the question: "Is giving the GMS satisfactory results as well for tidal and salty terrestrial embankments and levees?" Thus, the Humber estuary region, UK, has been chosen as a pilot site to realize quick geophysical survey methods by GMS in June 2010 at 3 localities: Tidal embankment Humber Estuary Fluvial embankment of Ancholme River Coastal Embankment Immingham. At each of the pilot sites, first measurements using the DEMP (Dipole Electromagnetic Profiling) method was performed. After having analyzed the data measured by the DEMP method, with the use of the software DIKINS, segments for the measurement by the method of resistivity tomography were selected (the segments with anomalous resistivity structure). The demonstration of the GMS at the dikes/embankments in Hull resulted in valuable findings. First, it is evident that the level of homogeneity of measured dikes in UK is much higher compared to the Czech Republic. Furthermore, all embankments show very low resistivity values. In dikes in coastal areas, saltwater seepage locations and their extent can be quickly mapped by means of the geoelectric methods.