Investigation of directional dependencies of P and S waves in shallow seismic and its surface geology evaluation

Determination of velocity anisotropy in shallow geological material contributes to mine exploration and operation and research of ground attributes. Orientation of fractures is very important while especially materials that contain fractures and cracks such as marble are extracted from underground. Therefore, we developed a method for determination of fracture orientations called the ?Fox Method?.Vertical fractures and cracks in isotropic background cause azimuthally anisotropy and this media can be described transversely isotropic media with a horizontal symmetry axis (HTI media). For Data acquisition, there are four radial geophone lines with angles of 45 degrees among them. Direct P and direct SH waves are recorded at the same time on geophone stations then seismic velocities are calculated. Seismic energy is emanated from five points of an octagonal plate with sledgehammer. This shot-receiver pattern is scrolled with same distances along parallel measure lines.Collected data are sorted in map coordinates and then wave surfaces are determined in points of measure area after velocities calculated into each direction are fitted ellipses. If media is isotropic, calculated wave surfaces are circle. Common orientation of fracture system in the media may be determined after major-axis, minor-axis and orientation value of calculated ellipses are defined. New map/graphic is obtained after these ellipses are set on the map along measure lines, so this new map/graphic is called the ?Eliptogram?. Eliptogram is a fracture orientation map.Otherwise, Eccentricity value of ellipses used to define anisotropy degree of the media. This value changes between zero and one. If this value approaches to zero, isotropy properties of media will rise. We obtain a map called the ?Homogeneity map? after contouring all eccentricity values. This map informs us about general homogeneity degree of the media.Limestone sample contain fracture systems was chosen in a dam area as application field and Fox Method was implemented. Finally, we demonstrated that results of this study are supported by the theory and observations.