A methodology for the rapid identification of neotectonic features using geographical information systems and remote sensing : a case study from Western Crete, Greece

摘要

The investigation of neotectonic activity is of high priority when dealing with inaccessible regions where a lack of data and a limited knowledge of the tectonic activity is often typical. There are various individual analyses that investigate features associated with neotectonic activity (for example geoinformatics, geophysical methods and field surveys). However, none of these methods combine low cost techniques based on geospatial and geophysical technologies with field validation of the outcomes. This study offers a methodology that covers all aforementioned approaches for detecting zones of neotectonic activity, linking computer-based observations with actual field observations and geophysical measurements. The combination of satellite imagery and DEM analysis can provide a cost-effective alternative to satellite radar interferometric analysis (InSar) and differential GPS monitoring. Crete is a complex, tectonically active region: an ideal “natural laboratory” to assess the interaction between neotectonic processes and geomorphological processes in landscape evolution and to test the effectiveness of geomorphometric methods for determining zones of neotectonic activity. Geoinformatic and geomorphometric techniques have been used here to assess landscape evolution in tectonically active zones. The results provide new information about the influence of tectonic and erosional processes on geomorphological evolution, with specific insights into the interactions between neotectonic deformation, faulting and drainage networks. Geomorphic indices have been used here to evaluate neotectonic behaviour at regional and local scales, identifying uplifted blocks, valley-floor tilting and zones of relatively intense neotectonic activity. Landsat ETM+ imagery and DEMs were used to discriminate lithological boundaries and identify lineaments. Field and VLF geophysical surveys verified that the lineaments coincide with faults. The GIS based multi-criteria decision analysis (MCDA) was considered as a strong approach to integrate the various factors associated with tectonic activity and to highlight, spatially, the potential zones undergoing active tectonic control.