Isabela Island Volcanoes

By Andrew Kozlevcar & Joseph Carollo

The Basics

Cerro Azul, Sierra Negra, Alcedo, Darwind, Wolf and Ecuador are the main six volcanoes in the Galapagos islands. However, there are many more and counting on this interesting Ecuadorian Volcano chain. Not only is the Galapagos expanding out to sea because of constant volcanic activity, but also towards the mainland of the continent, South America. Additionally, Isabella Island, which makes up 60% of the Galapagos, boasts one of the most interesting volcanic interactions in the world where six volcanoes are merging to create one huge island. In more detail, the miraculous islands have been around 3 - 5 million years, yet they have seen the most volcanic activity in that time period.

The Not So Terrible Tectonic Plates

The Nazca plate and the South American plate are key factors in building the volcanoes of the Galapagos. The Nazca plate being oceanic crust, is slowly sinking and moving toward the South American plate that will push the Nazca plate into the mantle where it will be melted into magma, thus a convergent boundary is occurring. When this happens, the magma will then begin to move through the crust and harden to build on each other creating a Shield Volcano. When the Shield Volcano is built, it will continue the cycle of magma cooling and creating more and more land as well as volcanoes. As this event is occurring, the South American plate moves the volcano off the hotspot allowing a new volcano to create while the older volcanoes are pushed to mainland, Ecuador.

Volcanic Breakdown

The Galapagos Island volcanoes are all created the same way, ultimately making them all the same type of volcano; Shield. These island building volcanoes have analogous features such as their lava type and eruptions. The lava types of these volcanoes are complimentary to their roles as they are in low viscosity and high in liquid which allows the lava to move quick and spread far before cooling creating islands. Likewise, the eruption produced by the volcano isn't very explosive as a result of low gas, yet it is perfect for creating islands and expanding land structures.

Galapagos Life and Volcano Effects

The people of the Galapagos consist of four islands (Santa Cruz, Isabela, Floreana, and San Cristobal) made up of 18,000 people who are mostly native to the Galapagos. Most citizens lifestyles include fishing, which wouldn't be possible without the volcanoes, more specifically lobsters, crabs, and a variety of fish. In addition, the natives farm on the land ultimately because of the rich soil while farming items like grains, tomatoes, blackberries, and passion fruit. On the contrary, living in this area gives an increase in danger with volcanic activity, increase in earthquakes, and fast magma. Based on that in the last 200 years the volcanoes have erupted 50 times and Wolf Volcano erupted last year (May 2015), Galapagos can be very dangerous yet hot as it is on top of the equator while reaching extreme heats higher than 90 degrees Fahrenheit.

Vocabulary

Plate - Each of the crustal pieces of the earth's lithosphere that together make up the earth's surface and crust


Mantle - The region between the crust (top) and the core (bottom) and is the thickest region of the composition of the earth


Convergent Boundary - A boundary where two plates collide and forms a variety of structures


Hotspot - A thin part of the crust where magma seeps to and creates volcanic activity


Viscosity - The thickness of a selected item