On the surface no nuclear explosion no matter the yield could do it, the atmosphere provides insufficient tamping for this and would simply be blown away into space above ground zero. To get enough tamping, the explosion would have to be very deep subsurface, probably hundreds of miles or more into the mantle. We can't drill a hole that deep.
I can think of four things that cause sudden changes to the earth's surface: Impact of a large object from space (such as Meteor Crater in Arizona), earthquake, volcanic eruption or explosion (Krakatoa is a prime example), and nuclear explosion (the atomic bomb caused very sudden and complete change to Hiroshima and Nagasaki). Every rain shower causes some change to the earth's surface, but I think you were asking about more dramatic examples.
Not known, probably the formation of francium fluoride. Plus, due to them being the MOST reactive elements, there would be a rather large explosion (the largest chemical reaction only exceeded by a nuclear reaction).
I am not sure what you are getting at. If I assume that you are asking the following: I am standing in the eye of a hurricane. I have a missile with a conventional warhead. I launch the missile and detonate it at the general altitude of the hurricane. What happens? Nothing. Nothing happens. When the missile explodes, a large portion of the shrapnel will go down to ground, but some of the shrapnel will cut into the strongest winds of the hurricane and be blown around. The explosion and the flying shrapnel is of an intensity that is too weak to actually destabilize the hurricane. If you use a nuclear warhead, the explosion will have an effect because nuclear weapons have environmentally destabilizing effects, but an environmental specialist would have to clarify it.
Designers try to establish the probability of such an event at less than 10-6 per annum, ie for any one reactor only one such event in 1 million years of operation. However this clearly depends on being able to predict failure rates of critical components such as the pressure vessel. We have an example of a catastrophic failure in the Chernobyl case, and there it is obvious that the designers had not anticipated all the ways that the plant could fail, and the failure rate for that design is too high. It is not being built any more, and in fact that design has not been built anywhere except in the former Soviet bloc.
What are large blocks of rock under the earth's crust?
A large enough body from space (comet, asteroid, meteor) that did not break up when coming through the Earth's atmosphere; a large sun flare or coronal blast; and a nuclear weapon detonation all have the ability to destroy entire cities and impair electronic communication systems.
Because mass and energy are equivalent, as Einstein showed, and even if you destroy a small amount of mass the energy released is very large.
You get a rather large explosion.
No, an asteroid cannot destroy earth, but a large enough asteroid can have devastating effects on the life on Earth
Enough of either U235 or PU239 to form a critical mass and hence a large explosion
a giant solar flare could technically destroy earth, but a solar flare could not get that large. however, theoretically, before our sun "dies," it will expand and destroy the earth.
A nuclear power station can not create a nuclear explosion. What CAN happen is that hydrogen could build up inside of the containment dome and if the build up becomes too intense, it can cause a hydrogen explosion, like the one in Japan recently. This explosion is dangerous only if you are close to it and are hit by the concussion or by the debris that is flying from the explosion. If this explosion is too large, it can damage the containment dome surrounding the reactor and this, in turn, releases some radioactive gases.
No. A lahar carries far less power than a nuclear bomb. However, large explosive eruptions, which can lead to lahars, can be as strong as or stronger than a nuclear explosion.
To destroy large areas of land. Is one answer. The other is to blackmail other countries into submitting to you.
If blackholes reach the earth the earth will destroy. Blackhole are to large it can eat star easily.
Anything 1 gigaton or larger could accomplish nothing more with its blast than blowing a large portion of the top of the atmosphere off into space. It would require a deeply buried explosion, probably deep in the mantle, to destroy the earth. This would probably require an extraterrestrial impact not a bomb. Such an object would probably have to be far larger than Mars.
While there have been a number of very large blasts used in mining, and accidents in making and transporting explosives, the largest non-nuclear explosion (not counting volcanoes) Was probably the spectacular accidental explosion of the N-1 rocket in the former Soviet Union in July 1969. The explosion was the equivalent of between 6-7 thousand tons of TNT.