A story released today by the Associated Press provides insight into the cause of earthquakes.
According to senior Iranian cleric Hojatoleslam Kazem Sedighi "Many women who do not dress modestly... lead young men astray, corrupt their chastity and spread adultery in society, which consequently increases earthquakes." Article here, with advice on 'formulas to repel earthquakes'.
Mr. Sedighi did not provide any information regarding volcanoes.
(A serious moment, though it isn't my natural preference. My heart goes out to the women and men of Iran, who must put up with the opinion of this pinhead and his cohort on a daily basis.)