Most people associate the Galapagos Islands with amazing birds & animals, but the good news for visitors is the islands are so much more than just a wildlife destination – Galapagos volcanoes, lunar landscapes & geology also play a bit part in the visitor experience!
Volcanoes in the Galapagos Islands shaped the landscape and created the archipelago. Out of 21 Galapagos volcanoes, 13 are still active, making the islands one of the most active hotspots on the planet.
Today, these remarkable volcanic landscapes and craters make for unforgettable photos, and the lucky few may even get to safely witness a spectacular eruption!
Keep reading for a guide to how Galapagos Volcanoes played an important role in the origin of the Galapagos Islands, and the the best volcanic sites that you can visit at Galapagos today.
The Galapagos Islands were formed by eruptions of underwater volcanoes over millions of years, until they broke the sea’s surface to form the islands we see today. The Galapagos Hotspot sits 3000 ft. under the water in the western part of the archipelago, close to the youngest islands of Isabela and Fernandina. Cracks in the ocean floor allow molten lava from the earth’s core to escape at the hotpost. As the earth’s plates shift, the older islands move away from the hotspot to the east, and their volcanoes became extinct, while new islands continue forming.
The oldest of the islands are South Plaza (4.2 million years) and Espanola(3.2 million years.) The youngest island is Isabela, which is roughly 0.7 million years old.
There are two different kinds of Galapagos volcanoes: The western islands tend to have large volcanoes with deep calderas, while the majority of those found in the east are smaller shield volcanoes. Shield volcanoes have gentle slopes and their lava has a low viscosity making it flow easier and covering a lot of ground.
Two types of lava flow can be found in the islands, A’a, and Pahoehoe. A’a is sharp and brittle, while Pahoehoe is smooth and ropy in texture. On any Galapagos tour, you will be able to see clear examples of both types.
Volcanic activity in the Galapagos is everywhere you look. Lava fields dot the landscape, and active and extinct volcanoes are found on both inhabited and uninhabited islands.
The Sierra Negra shield volcano and Volcan Chico parasite volcano on Isabela Island are a popular hike for those who want an active adventure. The trek takes you to the rim of the giant Sierra Negra caldera, where you can peer inside the crater to see evidence of old lava flows. Continuing to Volcan Chico where different shades of lava lend an otherworldly outlook on the island.
There are a few places in the islands where you can explore below ground in lava tunnels. Santa Cruz, Floreana, and Isabela Islands have areas that lead to expansive tubes that reveal the volcanic origins of the islands. The tunnels were formed when the top layer of lava solidified while the molten lava underneath kept flowing. Some of the lava tunnels are so large that visitors can walk into them, a good example is on Santa Cruz highlands.
Isabela and Fernandina Islands are the two most active spots for volcanoes in the islands. If your cruise itinerary takes you to the western side of Isabela, then be prepared for an unforgettable day with stunning volcano views on all sides. For the lucky few you may even find yourself in the hot seat when eruptions occur, with a front-row seat to see molten lava flows extending to the sea.
Los Gemelos or the Twin Craters are a pair of massive collapsed lava pits in the highlands of Santa Cruz. The craters are a great place to see Darwin’s finches while hiking the rims amid forested woodlands.
While other volcanoes around the world can pose threats, specifically the most recent eruption in New Zealand, the volcanoes in the Galapagos are constantly monitored. When events do happen, the Galapagos National Park takes precautions by altering routes or roping off areas that could be harmful to travelers.
Recent eruptions include Sierra Negra on Isabela Island and La Cumbre on Fernandina Island in 2018 and Wolf volcano on Isabela Island in 2015.
Sierra Negra on Isabela is one of the six Galapagos volcanoes that formed the island-all but the Ecuador volcano are still active. Historically, the eruptions of these shield volcanoes caused the evolution of the Galapagos tortoises on the island. Eruptions caused five different types of tortoise to evolve-divided by the geographic separation caused by lava flows the tortoise’s population became isolated and evolved depending on the terrain and food supply that each group could find.
The Sierra Negra volcano’s volcanic caldera is the second largest in the world, 6 miles in diameter and 300 ft. deep. Strong earthquakes in the Galapagos opened up fissures in 2018 on the volcano’s flanks and lava flowed down into the sea. The most obvious effects of the eruption were changes to the physical landscape. Among the positive effects are that new lava flows cooled by the ocean create new nesting areas for creatures like the Galapagos penguin.
La Cumbre Volcano on Fernandina Island is the youngest and most active Galapagos volcano. Continued eruptions cause dramatic changes to the landscape and also raise concerns for shore animals like sea lions and marine iguanas, while adventurous land iguanas risk everything to nest and lay eggs inside the crater rim to take advantage of the warmer environment. The Galapagos National Park monitors these events but rarely interferes as the eruptions are considered part of the natural cycle of the archipelago.
When Wolf erupted in 2015, experts and naturalists were concerned for the safety of the Galapagos pink iguana, only found on the flanks of the volcano, and the giant tortoise population which was part of a project to restore the creatures to healthy population size. As luck would have it, lava flows skipped the areas where both species live while creating amazing images at night as the molten rock flowed to the sea.
The Galapagos Islands are still forming around the eruptions on the archipelago. Over the next thousands of years, there will be radical changes in the landscapes and new islands forming. These events will have an impact on the wildlife and human population, but as the past has proven, adaptions will continue, species will evolve, and life will go on.
While most volcanic eruptions are caused by two plates rubbing together, the volcanoes that formed the Galapagos Islands were caused because of a hot spot. An area of the Earth ’s mantle where magma escapes from the layers in flux below the lithosphere.
The Nasca Plate moves east over the hotspot. Islands are formed after lava builds up under the sea to reach the surface-each new eruption creating another layer that eventually breaks into the air. In the recent decade, new volcanic islands have been formed in this fashion off of the coast of Russia and Japan.
As the Nazca Plate moves east away from the hotspot, volcanic activity subsides. In the Galapagos archipelago, the oldest islands are in the eastern waters and the youngest are in the west.
The islands are among the most volcanically active on Earth. Sierra Negra and Wolf volcanoes on Isabela Island erupted within the last fifteen years, and La Cumbre Volcano on the neighboring Fernandina Island became active in 2017.
The result of volcanic eruptions have created a maze of volcanic rock formations that range from the surreal moon-like terrain of Bartolomé Island, the lava bridges and pools of Los Tuneles on Isabela, and the rope strands of the pahoehoe lava flow on Santiago Island.
This architecture has contributed greatly to the eco-systems and diversity that reside within each island.
On Isabela, there are five different kinds of giant tortoises-separated by the six volcanoes on the largest island in the Galapagos.
As islands move farther away from the hotspot, the magma feeding the volcanoes dwindles, causing them to become dormant and eventually extinct. As time marches on, the calderas start to crumble, and the islands themselves start to sink.
Espanola and Santa Fe Islands have partial, extinct volcanoes, and one of the most popular snorkeling spots in the entire region is Devil’s Crown off of North Seymour. It is a partially submerged, eroded volcanic crater where sea life thrives.
Rocas Bainbridge, off of Santiago Island is a favorite among snorkelers and divers. The series of seven submerged and semi-submerged volcanic cones are home to crater lakes where flamingos gather, underwater shelves and walls are used as cleaning stations by sharks, and reefs where billowing schools of fish come to feed.
While each of the Galapagos Islands were formed by volcanic eruptions or uplifts from the seafloor, the landscapes of the archipelago are strikingly different. On Rabida there is a red beach, Floreana’s waterfront includes a black beach, and Tortuga Bay on Santa Cruz has one of the most beautiful stretches of white tropical sand in the world.
Santa Cruz, San Cristobal, and Floreana Islands have lava tubes and collapsed magma chambers to explore, and volcanic formations rising out of the water such as Pinnacle Rock in the bay of Bartolome have become the feeding grounds for penguins, green sea turtles, and sharks.
For more information about exploring the Galapagos Islands and discovering the volcanoes that created them, contact a member of our team.