hanging wall
- noun
- Specialized
- The geologist noted that the mineral deposits were located along the hanging wall of the fault.
Examples
-
During the excavation, the team encountered fractures in the hanging wall that indicated past seismic activity.
-
The hanging wall in the mining area showed signs of significant erosion over the years.
-
Work during 2008 was successful in discovering a new zone, the Phoenix discovery, of unconformity-hosted mineralization associated with the hanging wall of the quartzite ridge.
Blog text (22)
Surface Forms
Morphology
The constituents 'hanging' (suspended/above) and 'wall' (a side or vertical face) give a plausible image of an upper or overhanging side, so learners who know the words can roughly infer it refers to an upper side. However, the precise technical meaning (the specific position 'above the fault plane' and its contrast with the footwall) is domain-specific and not fully predictable from the parts alone, so it requires some specialist knowledge.
Etymology
Hanging wall comes from mining and geology: one block of rock sits above a sloping break and looks like a wall that is hanging over the gap. So, hanging wall means 'the upper side of a sloping break in the rock called a fault'.