Study of The Subsurface Fractures in Ayn-Sfni Plain/North Iraq from Azimuthal Resistivity Data

Abstract

Three locations (Jarahyah, AynSfni and Zenaho Merry) were chosen in AynSfni plain surrounded by Ayn Sfni,Kand and Maqlob anticlines. The data were processed by the graphs of cartesian and polar approaches via using offset Wenner spread with fifteen measuring spaces in six azimuthal directions. The Jarahyah location shows directions of perpendicular and parallel fractures related to the surrounding fold axes as well as a major fracture with oblique direction and vertical dip .Two fractures with vertical and medium dips in addition to minor fractures with medium dips are also displayed in this location. The analytical graphs of AynSfni location indicate more than five fracture systems characterizing with different frequencies and high to medium dipping angles.These results were compared with study of previous field measurements of Shaikhan anticline lies north of the present study. The graphs of Zenaho Merry location display fractures of different frequencies, directions and dips. These results identify large frequencies of perpendicular orientations with vertical and medium dips while the parallel orientations are reduced in the comparison with the two previous lacations. This result leads to the conclusion that there is a different tectonic nature of Zenaho Merry location.