2010-03-16_REVISION - M1981185 (29)

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Wildcat Mining Corporation Page 23 earlier sills, with some replacement and assimilation of their wall rocks. As a result of this intrusion, the late Paleozoic and Mesozoic sedimentary section has been inflated some 6,000 to 8,000 feet. In the May Day mine area, porphyry dikes fill fractures parallel to or within the May Day, Idaho and other east -west fault zones. At certain points the ore leads are noted cutting across the dikes or ramifying through them, while at other places portions of the dike are displaced from a few tens to hundreds of feet by post - mineral faults. This is strong evidence that igneous intrusion, faulting and mineralization were all elements of a single multi -phase intrusion, deformation, and mineralization event. Structure The principal structures in the vicinity of the May Day and Idaho mines are the numerous faults of the May Day -Idaho fault system. This group of faults strike east -west with steep dips both to the north and to the south. The total vertical displacement along the faults is 350 to 475 feet, and marker horizons such as the Pony Express limestone show an apparent horizontal displacement of 1000 to 2000 feet to the east on the south side of the fault system. In places, the faults are single fracture planes; elsewhere displacement is distributed though several fault splays. • The most continuous of the diorite - monzonite porphyry bodies exposed in the mines follows the length of the Idaho fault. Most of the exposed contacts of this dike are faults marked by abundant gouge. Economically more important, however, is a set of normal faults that strike generally north -south and dip eastward at 55 to 85 These faults, with smaller displacements of 10 -30 feet, contain the principal ore deposits of the mines. All of these faults terminate against, or are displaced by, the east -west faults of the May Day -Idaho system. The complex geometry of the south - dipping stratigraphy, the major east -west striking faults, and the north -south striking vein - filled fractures is illustrated in the geologic map of figure 4 and the map and block diagrams of figures 6 and 8. There is not agreement among geologists regarding interpretation of the structure. Most mine geologists (Garrey, 1928; Anonymous, 1929; Fominyah, 1936; McCausland, 1941) believed that the east -west May Day and Idaho faults are post -ore and that they displaced the north -south ore veins horizontally. Thus, the Idaho, Valley View, and "810- foot" veins are considered as displaced segments of the same vein. The May Day and Brooklyn veins are similarly related. 0 January 2007 May Day — Idaho Mine Colorado