Subject: Can rocky islands be electric after vulcanic eruptions

I've experienced several forceful electric shocks on the island 
of Folegandros close to Santorini in the Aegean sea. 
Particularly in the shower, and when swimming in the sea reaching 
out to touch some rocks. According to the locals it happens all 
the time, they say the island is electric! I know that the 
Santorin eruption in 1650 b.c. accumulated a lot af electricity, 
but could that still be 'contained' in the surroundings?

Re: Can rocky islands be electric after vulcanic eruptions