Riflettanza di rocce di faglia in carbonati: il caso della faglia di Campo Imperatore (Gran Sasso, Italia)

The Vado di Corno fault zone (Campo Imperatore - L’Aquila) is a normal fault system that develops within Southern Appennines into carbonate rocks. Comminution and pulverization are characteristic processes of fault zones on these rocks. Given that grain size reduction produces reflectance variations in rocks and minerals spectral signatures, I carried out spectroscopic analyses on powders at different grain size (800, 200, 63, 10 μm) as well as on slabs fault rocks to analyze their reflectance variations. The obtained data show two different type of relationship between spectral parameters and grain size in fault rocks: a reverse one between reflectance and grain size values and a direct one between absorption peak depth and VIS-VNIR slope with respect to grain size. In other words, reflectance increases with decreasing grain sizes, whereas VIS-VNIR slopes and carbonate main absorption band depth increase with the grain size. Hence, fault rock recognition and classification from remote platform can be possible if adequate spectral and geometrical resolutions are provided. For this reason, the spectral signatures of the analyzed fault rocks were resampled with the wavelength ranges and spectral resolution of Worldview2 and Worldview3 sensors which at present acquire the best resolved data of the Earth surface from orbit. The final results suggest that the satellite remote sensing identification of comminution and pulverization in fault zones on carbonate rocks is a feasible