Research into vulcanic vents

The Daily Herald writes that an international team of volcanologists visited Saba last week to study its geology. Following their assessments, they also met with Island Governor Jonathan Johnson on Friday, to submit some recommendations.

Richard Arculas from Australian National University in Canberra and Jon Bludy, George Cooper and Luca Ziberna from Bristol, England, were guided by Saba Conservation Foundation Ranger James Johnson and park volunteers Paul and Sue Fleuren on an extensive survey of Saba’s volcanic vents. These vents tend to be located on the highest places on Saba, such as Mt. Scenery, which was among visited sites. Some of these vents produced poisonous gases as recent as two years ago, but are currently inactive. This inactivity is a common occurrence when gas forms alternative escape routes for surfacing. Among highlighted dangers, experts indicated that the cliff at Wells Bay is most unstable and among the most dangerous they have observed.

On April 1, the team inspected a recently discovered volcanic vent on Paris Hill, a 10-meterdiameter area recently identified by The Bottom resident Cornel Johnson, who reported it to Ranger Johnson. The new vent presents blackened soil indicative of hydrogen sulphide and sulphur dioxide gas. The discoloured area lacks any vegetation in its proximity. The volcanologists believe Paris Hill may have been the location of Saba’s last volcanic eruption; an important statement as the island’s administrative “capital” The Bottom is surrounded by three such volcanic domes. The inspection at Wells Bay resulted in finding plenty of cumulate, a type of rock formed several kilometres below the surface. Multiple samples were taken for further lab study in Bristol. The crystals in these rocks survived propulsion from within the Earth’s deep crust without melting. These rare materials could provide scientific insight into various geologic processes related to volcanic temperature and pressure.

During a visit to the Sulphur Mine, the experts discovered a colony of resident bats and collected celestine, sulphur, magnetite and gypsum soft crystals formed by condensing vapours. They also inspected the tide pools at Cove Bay, which present a collection of “volcanic bombs,” rocks that were exploded from the volcano. Two fulgurites were discovered on site. These are rocks formed when lightning melts the surface of the rocks, creating a layer of glass that gives the appearance of wet rock. Samples were also taken from this site for later study.