When the volcano blows …

Surtsey burst onto the scene in 1963. It was a new island, announcing its entrance with smoke and steam as it broke the waves of the North Atlantic off the southern coast of Iceland, a volcanic product of the Mid-Atlantic Ridge, where the Atlantic Ocean widens a few inches per year, divided by a massive submarine mountain chain.
Someday soon Kick-Em-Jenny may follow in Surtsey’s footsteps.
Kick-Em-Jenny is a submarine volcano six miles north of Grenada, near the southern end of the Lesser Antilles, the arcing archipelago that encloses the eastern end of the Caribbean. It’s the Antilles’ southernmost active volcano and its only active submarine volcano.
Kick-Em-Jenny lies atop the subduction zone where the expanding Atlantic Plate meets the Caribbean Plate. The earth’s surface is composed of several tectonic plates on which ride the continents and ocean floors, creating mountains, earthquakes and volcanoes where they collide. The subduction zone, where ocean crust from the east dives under Caribbean crust to the west toward the mantle, gave rise to, and is still creating, the West Indies. Subduction creates the ocean’s deepest spots: the Puerto Rico Trench at 28,230-plus feet is the Atlantic’s deepest point and the second-deepest in the world after the Mariana Trench in the Pacific.
Kick-Em-Jenny has erupted at least 12 times since 1939, when a black cloud rose 885 feet above the sea. Its basal diameter is three miles, it rises about 4,300 feet above the sea floor, and it is about 590 feet below sea level. In the 1970s and early ’80s its depth decreased to about 490 feet below sea level as a lava dome grew in the crater. It was thought for a time that Kick-Em-Jenny would crest the surface by 2000, but the dome collapsed in the late ’80s, and in March 2002 the depth was reported to be back to 590 feet.
Kick-Em-Jenny, along with Mt. Pelee, which destroyed St. Pierre, Martinique, in 1902, and the Soufriere Hills volcano on Montserrat, is one of a volcanic fraternity that has been at once man’s bane and his sustenance. A volcano is the provenance of rich soil that nurtures plants and animals, enticing men to return, despite the danger, to its shadow again and again.
Montserrat’s volcano long lay dormant, but in July 1995 it roused from its centuries-old slumber. Soufriere is a generic French term for a mountain that gives off sulfurous gases, and the Lesser Antilles thus contain a few Soufrieres The first large phreatic eruption, a steam-driven explosion caused by heated water, on Aug. 21, 1995, covered the capital city, Plymouth, with a thick ash cloud, and southern Montserrat was evacuated. Another large phreatic eruption on Oct. 30, 1995, was followed by pyroclastic flows avalanches of ash, pumice, rock fragments, and volcanic gas traveling 50 to 100 mph in 1996. The term pyroclastic flow was soon as familiar to the residents of Montserrat, from school children to farmers, as lake-effect snow is to Ohioans.
These events were but the prelude to Soufriere’s thunderous magmatic explosion on Sept. 17, 1996. The ash plume rose to 40,000 feet, and 600,000 tons of ash were deposited in southern Montserrat.
Jimmy Buffett recorded his album “Volcano” on Montserrat in the late ’70s, the title song a tongue-in-cheek look at the volcano’s effect on island life. While there, he hiked to the crater, took mud baths, fed mangoes to giant iguanas and had his photo taken next to the volcano vent.
Returning on Jan. 14, 1997, shortly after Plymouth was again covered with ash, he couldn’t recognize the coastline from his last visit just two years earlier. The top and one side of the mountain were gone, and the landscape, he said, was a cross between Iwo Jima and La Brea tar pits.
More major pyroclastic flows descended the mountain in April 1997, killing people who ignored the exclusion zone order, and the volcano exploded again later that year. That year saw the peak of activity in the Soufriere Hills, but the volcano has not returned to its former quiescence.
Volcanoes are often described as destructive because they destroy man, livestock and buildings, but they are also engines of creation, possibly the most visible examples of the normally sluggish pace of geological forces.
Some of us may live to see Kick-Em-Jenny become the newest member of the Lesser Antilles, but one never knows. Volcanoes resemble the frog-in-the well math problem, falling back two feet for every three feet forward. When it does make the map, Kick-Em-Jenny will quickly be colonized by plants and animals, that, like daring humans, can’t resist a new piece of land.

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