Walking on a volcano

Yesterday our group from the Boys & Girls Clubs of America got the chance to tour Thera's modern volcano. We took a short boat ride from Fira to Nea Kameni, the volcanic island in the middle of the caldera.

We were met by Dr. Haraldur Sigurdsson who came on a shuttle boat from the R/V Endeavor.

Nea Kameni means "new burnt island." The island was formed by a series of volcanic eruptions, starting in 197 BC. During each eruption, melted rock called magma came up out of the Earth and slowly built the island. At first, the hot rock emerged under the water, causing violent explosions. Eventually the base of the island grew until it reached the surface of the water.

Later eruptions happened over hundreds of years, and the island slowly grew in stages. Walking around, you can actually see different areas that were formed at different times. Plants provide one clue. Older portions of the island have had more time for plants to get established. Newer lava is rough and is harder for plants to grow on.

There has not been an active eruption of Nea Kameni since 1950. Yet there is clear evidence that the volvano is still hot. Hot water called hydrothermal fluid seeps out of the rocks around the edges of the island. These fluids carry minerals, which form a reddish deposit on the rocks.

In some areas, the hot hydrothemal fluids form hot springs which are popular places to swim. We ended our tour with a short swim before returning to Fira.

View more photos from Nea Kameni. 

Todd Viola
Immersion Presents

Immersion Program: 
JASON Learning: A Partnership of Sea Research Foundation and National Geographic