Vahid E.Ardestani - PH,D, Associate professor
Mohammad Ali Ahmadi - MS.c, Student

The total horizontal derivatives of gravity foelds can be a useful aid to its interpretation. A normalized version of it wich is called TDX fillter and is used to determine t+AF266e edge of gravity data and results are compaared to analytic signal method whiich is a classical edge detection method. Key Words: Edge d detection, gravity anomalies, total horizontal derivative filter