Can bedrock be broken by earthquake or volcano?
My bet is volcanoes can crack through bedrock.
36-40, M
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exchrist · 36-40
@MsSwan yes my thoughts too. Someone on here was telling me bedrock cannot be effected by endless construction on top of it. I’d hypothesized perhaps bedrock being compacted could explain the sinking of manhattan island in combination with sea level rise. The user then seemed adamant that bedrock is unbreakable.
@MsSwan This s what Google says.
Yes, an earthquake can break bedrock, particularly if the rock is already weakened by existing cracks or faults. Strong earthquakes can fracture bedrock, leading to damage and contributing to hazards like rockslides in subsequent seismic events.
ArishMell · 70-79, M
@MsSwan It's really the other way round, for major earthquakes.
The fault or thrust-plane already exists, and the tremor is the vibration of one mass of rock suddenly sliding on the other. It will break rocks deposited on top if the "re-activated" fault has been stable for long enough for that to have happened
This type of slip is associated with continental collision: one crust plate sliding over the other (usually ocean floor plate subducting below a continent as along the Pacific coasts); and with crustal extension. In the latter the crust is being stretched and eventually cracks with one wall of the fault sliding down the other.
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Volcanoes as such cause fairly small local earthquakes as the rising magma pushes its way towards the surface, melting and cracking its way through the Crust as it does so.
However, the whole process is rather more complicated than that; depending for a start whether the volcano is above a plate subduction (e.g. the Pacific "Ring of Fire") or plate fracture (Mid-Atlantic ridge and the island of Iceland.)
Or rarer, is like Hawaii, considered to be a giant volcano atop a convection plume of magma under a Pacific floor Crust plate.
The fault or thrust-plane already exists, and the tremor is the vibration of one mass of rock suddenly sliding on the other. It will break rocks deposited on top if the "re-activated" fault has been stable for long enough for that to have happened
This type of slip is associated with continental collision: one crust plate sliding over the other (usually ocean floor plate subducting below a continent as along the Pacific coasts); and with crustal extension. In the latter the crust is being stretched and eventually cracks with one wall of the fault sliding down the other.
.
Volcanoes as such cause fairly small local earthquakes as the rising magma pushes its way towards the surface, melting and cracking its way through the Crust as it does so.
However, the whole process is rather more complicated than that; depending for a start whether the volcano is above a plate subduction (e.g. the Pacific "Ring of Fire") or plate fracture (Mid-Atlantic ridge and the island of Iceland.)
Or rarer, is like Hawaii, considered to be a giant volcano atop a convection plume of magma under a Pacific floor Crust plate.