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4 noticeable normal fault offsets of up to 2 inches. The down-dropped faults were characterized by a strike of N 80° W. Observations continued approximately 800 feet to the southwest, on a broad, flat plain of mud on a topographic saddle located approximately 400 feet south of the "Grand Canyon." A series of thin tension cracks were developed in the mud, with an approximately east-west trend (figure 6). Running water was heard beneath the ground surface neaz the thin cracks. Observations proceeded to the topographically highest point behind the slump, which represents the southernmost extent, and also the head, of the failure area. This azea exhibits characteristics of a rotational slump failure. From previous vantage points on the east side of the failure, the "Grand Canyon' was oriented along a heading of S 70° W. When the head of the failed area was approached from the south, a series of normal faults were encountered. The N 50° W-striking normal faults offset the soil and regolith, exposing fault scarps in soil between 4-5 feet high, and spaced approximately 200 feet apart. At this location, the normal faults are parallel to the "Grand Canyon' and located behind it, defining the boundary of rotational failure in the slump azea (figure 7). The "Grand Canyon' represents an arced failure, as defined by its N 70° E trend on the east side of the failure area, and its change in orientation to N 50° W on the southwest side of the failure azea. Observations retreated back to the exposed H seam, and .resumed on the western boundary of the failure area. The boundary was distinctly represented by a transverse ridge of rubble formed by shearing along an interpreted strike-slip fault, separating the area of ground deformed in the failure event from adjacent, undeformed ground. A major haul road entirely contained within the defonned block had been offset along an internal strike-slip fault by approximately 260 feet, as determined with a laser range finder. Additional faulting of the soil and regolith had continued within the prior week, according to mine management, forming chasms with a strike of approximately due north. Lazge blocks within the deformed area remained intact while moving, as evidenced by long portions of the haul road that remained smooth and unbroken. Other portions of the haul road were extensively fractured and bent, indicating significant deformation of underlying soil or rock that propagated to the surface due to the unevenness of the sliding planes (figure 8). DISCUSSIONS Geologists refer to all downslope movements, whether very fast or imperceptibly slow, as "mass wasting." Movement along a cleazly defined plane is referred to as a "slide' and the free sliding of recently detached segments of bedrock on a sloping joint or bedding plane constitutes a "rockslide." Thus, the mass wasting event at the Trapper Mine is interpreted to represent a very large rockslide, in which a sequence of largely intact strata slid down-dip along one or more bedding planes. The head of the rockslide exhibits chazacteristics of a "slump;' which is a form of slide motion in which a mass of