l>Normal Faults
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Normal Faults

To correctly identify a fault, friend must an initial figure the end which block is the footwall and which is the hanging wall. Climate you identify the loved one motion between the hanging wall surface and footwall. Every fault tilted native the vertical has actually a hanging wall surface and footwall. To recognize which is which, visualize yourself creating a mine in follow me the error plane. The block listed below your feet is the footwall, and the one upon which you would hang your miner"s lamp is the hanging wall. It is that simple. Strike-slip faults space vertical and thus perform not have actually hanging walls or footwalls. If the hanging wall surface drops relative to the footwall, you have actually a typical fault. Regular faults happen in areas undergoing expansion (stretching). If friend imagine undoing the movement of a common fault, you will undo the stretching and also thus shorten the horizontal distance between two clues on either side of the fault.

You are watching: Which fault will see the hanging wall move down relative to the footwall

If girlfriend stood ~ above the fault plane, the block on the appropriate would be under her feet. This is thus the footwall.The red heat marks tantamount layers ~ above opposite next of the fault. Because the hanging wall surface dropped relative to the footwall, this is plainly a typical fault.

Photo: thick limestone bed in northerm Mexico, by Norris W. Jones

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The striking black layer is a welded tuff (volcanic ash that remelted itself to become solid glassy rock). There room three common faults in the pink tuffs to the best of the welded tuff. In ~ the feet of the human being is the very same orange layer together the faulted one seen just above the roadway in the middle of the photo. A 2nd fault cut the orange layer in the center of the photo. A third one runs from the left end of this faulted layer under to the person.
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Normal faults frequently occur in pairs, v one gift the main fault and also the various other being a smaller sized conjuagate fault.The red lines show the counter on the right-hand fault. Offered the angle of the fault, the upper red heat is top top the footwall, the lower red heat is top top the hanging wall.

Bishop Tuff lake sediments, Owen Valley, CA.

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This hill of unique layers limestones mirrors several to adjust of typical faults offsetting the significant white band close to the top of the mountain. If you focus on each fault, the counter of each hanging wall from each foot wall surface indicates typical fault motion.Near the gyeongju Track, fatality Valley, CA
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Many regular faults have so much offset the you cannot trace individual beds across a solitary outcrop. However, sometimes the beds have been bent by the dragging the the hanging wall over the footwall.

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In this case, the beds on the best of this fault have actually been bending downwards by common fault motion.

Mosaic Canyon, death Valley, CA

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