This report presents the geometric parameters (attitude, spacing, extent, and aperture) of fracture patterns in a selected portion (study area) of San Manuel Copper Mine, Arizona. The geometric parameters are quantified for input to structural analyses for studies of the influence of fractures on cavability of ores. Using an orientation analysis procedure developed earlier by the Bureau, three prominent and nearly orthogonal sets of fracture orientation were delineated in the study area. Sets 1 and 2 dip nearly vertically, and generally strike east-west and north-south, respectively, whereas set 3 is nearly horizontal. Both a horizontal rotation (of 14 deg to 26 deg for sets 1 and 2, respectively) and a tilt (of 20 deg for set 3) is shown to occur between the 1415 and 2015 levels of the mine. Comparison of the three major rock types present in the study area (quartz monzonite, monzonite porphyry, and rhyolite) show that the rhyolite is characterized by short extent, small spacing, and tightness of fractures as well as the general absence of fracture set 3, which may account for its generally observed strong resistance to caving.