Natural calamities caused by the force of nature is inevitable and if the damage to properties especially to power lines and communication infrastructure, these can really affect the volume of a certain crypto and may affect a slow trend downwards.
To some extent you are right that the demand for crypto will be affected and those people who are damaged due to natural disasters would not be able to invest in cryptocurrency. With low demand price may fall and for a period of time the whole crypto market will go down, but it is not sure that natural disasters will surely influence the crypto market.
I think if an earthquake will occur especially a strong one,it will automatically lost the signal and internet access in that particular area will shut down.Crypto transactions will be paralyzed temporarily but when we talk of the crypto market,i think it will not be affected that much.