footwall

[foo t-wawl] /ˈfʊtˌwɔl/

noun

Mining. the top of the rock stratum underlying a vein or bed of ore.

Compare hanging wall (def 1).

Geology. a mass of rock lying beneath a fault plane.

Origin

1640-50; foot + wall

Examples from the web for footwall

If the fault surface is exposed, the footwall is the side onto which water would drip.
Sulfides may intrude fractures in footwall country rock.
Ingress of sulfur through fractures in footwall may be important ore control.
footwall rocks are highly oxidized, sheared, and cut by anastomosing quartz-sulfide veinlets.
The color shows the amplitude of dislocations and white arrows represent the motion of the hanging wall relative to the footwall.
The colors show the slip amplitude and white arrows indicate the direction of motion of the hanging wall relative to the footwall.
The section south of the fault is the footwall and the northern part is the hanging wall.
Cordierite and anthophyllite in footwall of metamorphosed deposits, graphitic schist in hanging wall.
Surface location of a fault in which the hanging wall has moved downward relative to the footwall.
Both the hanging wall and footwall must be strong, since there is no support in the slopes.

British Dictionary definitions for footwall

/ˈfʊtˌwɔːl/

noun

the rocks on the lower side of an inclined fault plane or mineral vein Compare hanging wall

footwall in Science

footwall

(ft'wôl')
The block of rock lying under an inclined geologic fault plane. See more at fault. Compare hanging wall.