Scientists have discovered previously unknown volcanoes in the ocean waters around the remote South Sandwich Islands. Using ship-borne sea-floor mapping technology during research cruises onboard the RRS James Clark Ross, the scientists found 12 volcanoes beneath the sea surface -- some up to 3 km high. They found 5 km diameter craters left by collapsing volcanoes and seven active volcanoes visible above the sea as a chain of islands....