In my world there is such thing as a temporal weapon: a device which radically alters the flow of time in a given region by fueling a warp drive-like device with the concentrated energy of a thermonuclear explosion. The vast majority of temporal weapons stop time in a given radius: they generate an explosion of plasma that generates a particular spacetime deformity resulting in a singularity at ground zero and a large region where time is so severely dilated that, inside the effective radius, seconds will pass while outside thousands of years go by. (Photons and other particles that travel at light speed - "luxons" - are unaffected by the time dilation, but all slower-than-light particles - "bradyons" - are affected. Since most material is bradyonic in nature, there's virtually nothing that a temporal weapon won't work on.) Soldiers (and civilians) caught in the effective radius of a temporal weapon will notice the effect dissipate after about 30 seconds, but in that time a dozen millennia will pass for the outside world.
In space, temporal weapons can be used to destroy an entire fleet, because if you stop time for the opposing fleet and just let them sit in orbit, their ship will be bombarded by so much radiation over time that by the time the ship's crew notices the detonation after a few seconds of being stopped in time, they will have already received a lethal dose of radiation as centuries or millennia have passed in the outside world and even armor that absorbs 99.9995% of space radiation will not have been designed to withstand thousands of years of radiation. Besides, once the effect wears off, the war they were fighting will most certainly have already ended.
However, when detonated on a planet, the temporal weapon's time-stopping field spreads through the dense solid matter of the ground, effectively removing the tectonic plate's entire momentum over the course of a few minutes, including stopping its rotation relative to the planet. This happens gradually enough that it doesn't produce instant supersonic winds across the affected continent - the temporal weapon uses a fusion bomb as fuel, so there are stronger winds there already - but approximately 200 seconds after detonation, the continent on which the weapon was detonated is stationary in the geocentric non-rotating frame.
This is obviously a weapon of mass destruction, and is used in far more dire circumstances than nuclear weapons.
Question: how long does it actually take for a tectonically-active Earth-like planet to become uninhabitable if a temporal weapon hit a continent? My guess is that a tectonic plate suddenly gaining ~400 m/s relative to the ones around it would be definitely catastrophic for people nearby the fault line and possibly devastating to life on the rest of the planet, but I'm not sure how fast it would be. It is a necessary element of temporal weapons in this universe that they stop tectonic plates which ultimately result in the uninhabitability of a planet or at least a large section of it, but as far as the science of tectonics goes I am not sure exactly how long this process should take.
Assumptions we can make-
- The temporal weapon detonates with a small enough effective radius (probably on the order of a few cubic kilometers) that weather systems and the like are unaffected by the stopped time
- The target planet is geologically Earth-like (physically more Titan-like), with tectonic activity negligibly different from Earth; its rotation period is halved, so days are 12 hours long, and its radius is about 2,750 km
- I then calculate that the velocity in the geocentric non-rotating frame of the surface of the planet is moving at about 400 m/s
- At T-0, the weapon detonates, and as the field permeates the continent the tectonic plate begins accelerating at ~2 m/s until T+200 at which point acceleration stops
- Reaction forces still apply to the plate to slow it down or reduce its acceleration but the weapon is providing enough force to maintain 2 m/s in a vacuum for 200 seconds
