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Earthquake damage to the Custer Hotel in Mackay. One of the most severe hazards to people during earthquakes is falling masonry and parapets. This view shows the low strength of untied brickwork when shaken by horizontal earthquake forces.

Earthquake damage to the IGA store in Mackay. Many attachments to buildings have strength in the vertical direction only, i.e., strong enough to prevent falling due to gravity. Strong horizontal forces during the earthquake knocked down this store-front cover, and presented an extreme hazard to people trying to exit the building.

Multiple fault scarps on the Lost River Fault. Borah Peak is visible in the background.

View of Lost River fault scarp crossing Double Springs Rd. View from graben, observer side down.

Car crushed by debris from earthquake-damaged building in Mackay. Falling bricks can be killers!

View of the Lost River fault scarp, looking northeast from Doubleapring Road, showing vertical offset of the road. A downward curve of the upthrown side of the fault is a relict from an earlier earthquake-generated fault movement. Vertical displacement of the ground along the fault during the 1983 earthquake is approximately the height of the freshly broken ground, or somewhat more than the height of the people standing nearby.

View of the headwall and rotated blocks in the upper part of the Birch Creek landslide. Note the sag ponds impounded by the rotated blocks. The landslide probably started at the same time as the intense earthquake vibrations, but because landslide debris covers the fault scarp, the landslide was active longer than the time it took for the fault scarp to form.