Evaluation of the tectonic activity of faults with mineral alterations: A case of East Anatolian Fault-Palu Segment, Turkey

Abstract

Palu segment is a part of the Eastern Anatolian Fault Zone (EAFZ), the most important active left-lateral strike-slip fault system in Turkey, and there are different mineral alterations in this zone. In the study, the spatial relationship between tectonic activity and mineral alterations was tested with the Getis-Ord Gi* statistic in and around Palu segment. Mineral alterations at the pixel level were determined from ASTER images by Ratio, Relative Band Depth (RBD), Mineral Indices, CROSTA, Constrained Energy Minimization (CEM), Mixed Tuned Matched Filter (MTMF) methods. According to the results, the spatial distribution of alteration minerals extending parallel to tectonically active fault lines and/or partially bounded by faults in the area. RBD, Mineral Indices, CROSTA, CEM, and MTMF image processing algorithms applied in the study gave consistent results in the spatial determination and mapping of hydrothermal alterations in the study area. At 99% and 95% confidence intervals, statistically significant cold spot clusters indicate the proximity of alterations to faults concentrated around fault lines. This degree of clustering of mineral alterations indicates regions with high alteration rates close to fault lines and areas with tectonic activity along fault lines.