This study provides a description and statistical analysis of fold-related fractures in the Khur fold, northeast of Kopet Dagh fold-and-thrust belt, Iran. Kopet Dagh fold-and-thrust belt, as a part of Alpine-Himalaya orogeny belt in west Asia, forms the northeastern boundary of Iran plateau. In this study, the remote sensing technique was utilized to map and statistically analyze the lineaments on the satellite images. Extraction of fractures is based on the processing of satellite images and completed by field observations. Based on their directions, fractures can be categorized into four sets including an axial and a cross-axial set that trend parallel and perpendicular to the fold axial trace, respectively, and two oblique sets that trend at moderate angles to the axial trace. The mean trends of the principal compressional stress, independently calculated for the fold-related fractures systems, are close to N41° ± 5°E and are perpendicular to the general NW-SE trend of the Kopet Dagh fold-and-thrust belt. The cross-axial set is interpreted as the oldest set. The major orientation of lineaments is NE-SW. Also, the length distribution of fractures shows a right-skewed distribution. To extract the underlying scaling parameters, the dataset was analyzed using Maximum Likelihood Estimators (MLEs). It was found that a lognormal distribution is the best representative statistic for fracture lengths in the study area. The combination of information from the prepared fracture map, the analysis and measurement of the fractal dimension, and calculations of variables such as density and intensity revealed that the high probability of permeability along with fractures with an NW-SE trend.

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