Database of granite crack in northwestern Tsuruga Peninsula

Terusawa, Shuji; Shimada, Koji   

Cracks (joints, fracture zones, etc.) are formed in granite by various mechanisms. Faulting uses these pre-existing cracks as weak plane. In addition, there may be directionality in the direction of the crack, producing a linear valley. Attempts are also being made to estimate a regional stress field from the direction of excellence. In this paper, we developed a database of cracks in granite by compiling 5050 points of strike-dip data, as part of the geologic surveys of the Monju fast-breeder reactor located in the northwestern part of the Tsuruga Peninsula. The strike-dip is predominantly northern northeast to northeast strike and high angle east dip, but shows different characteristics for each place. Therefore, further analysis using this database is desired.