T-LIDAR imaging of active faults - Does fault-surface roughness reflect repeated coseismic slip events?

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Main aims of the planned investigations are to analyze the tectonic geomorphology and paleoseismology of known active faults that display post-glacial fault scarps with groundbased laser-scanning techniques (T-LIDAR – terrestrial Light Detection And Range) to reconstruct the faulting history along surface-rupturing scarps, and to test the potential of selected locations to calibrate the roughness-index method for active faults. LIDAR techniques will be used for surface evaluation of limestone bedrock scarps and roughness analysis of the scarp surfaces. As the footwall of a normal fault undergoes continued uplift, the development of fault scarps by repeated earthquakes forms a steep polished fault plane (free face) that is subject to differential weathering through time (degradation, karstification, bio-erosion). Therefore, the upper parts of scarps are usually characterized by more intense weathering in comparison to the base. Goals of the LIDAR investigations are to reveal the slip history of known and dated active faults and to establish a relative age estimation of the coseismic slip events along limestone fault scarps in the Mediterranean region (e.g., Greece, Italy, FYROM). Furthermore, the LIDAR approach and the point cloud analyses have a potential to constitute a supplementary methods for the absolute dating with cosmogenic nuclides. If the relative age assessment will be successful, controlled sampling for the costintensive absolute dating, hence, expenses may be reduced and time economized for scarps, which developed since the last glacial maximum (LGM).