basically, stress.
the two plates will be moving either against each other or towards each other with one submerging below the other. stress will build up and at some point the stress will be released by an earthquake allowing the two plates in question to move.
The friction between the plates. When the friction is resolved, an earthquake occurs.
The North American and Caribbean tectonic plates caused the Haiti earthquake in 2010. The movement along the boundary between these two plates resulted in the devastating earthquake.
Irregularities in Earth's plates shortly before an earthquake can be due to the buildup of stress and pressure along fault lines. This stress can cause the plates to stick and deform, leading to irregularities in their movement. When the stress becomes too great, it can trigger an earthquake as the plates suddenly release the built-up energy.
Cataclysm is the end of the world while and earthquake is just the tectonic plates shifting.
The tectonic plates involved in the Haiti earthquake are the Caribbean Plate and the North American Plate. The earthquake was caused by the movement along a strike-slip fault between these two plates.
pressure builds under the plates
Assuming you are talking about the earthquake in Japan, the two plates are the Pacific and the Asian plates.
The Kobe earthquake was caused by the Philippine Sea Plate and the Eurasian Plate. The earthquake occurred along a fault line between these two plates in the southern part of Japan.
South Carolina 1886
As far as I know the result is an earthquake.
The earthquake tranforms boundary between the two tectonic plates.
As a result of the sudden shift between two tectonic plates, an earthquake occurs. This sudden movement releases energy in the form of seismic waves that shake the ground, causing the Earth's crust to break and deform. The intensity and impact of the earthquake depend on the magnitude of the shift and the location of the plates.