The college of science at the University of Basrah organized a seminar on "assessment of structural and tectonic boundaries using the gravitational method in Diyala province, north-eastern Iraq", and the seminar aimed at using the total horizontal derivative (THD) technique, where the researcher was able to identify subsurface fault lines using the gravitational method. The seminar, which was attended by a doctoral student (Fadel Abdul Abbas Obaid), included a study conducted using the gravitational method to assess the structural and tectonic boundaries in Diyala Governorate. Using the total horizontal derivative (THD) technique, it was possible to identify fault lines in the prevailing directions in the region heading in the north-west-south-east (NW-SE) and north-east-south-west (NE-SW) directions by applying the CET analysis technique.