Fernandina Island
Today we visited Isabela and Fernandina, the youngest islands in Galapagos, located on the western side of the archipelago. This area is also the richest area due to the upwelling and the quantity of food and plankton that animals can find here. This morning we took Zodiac cruises along the coastline of a collapsed volcano, where highlights included a small pod of bottle-nosed dolphins swimming alongside us. This was followed by a snorkeling outing in the same area, where we had the chance to swim among different kinds of tropical fish, sea lions, sea turtles, a devil manta ray, golden rays and even the elusive oceanic sun fish (Mola mola): it was truly incredible.
During the afternoon we sailed along the coastline and observed the active volcanoes that form these two islands. We proceeded to disembark on Fernandina, the most pristine island in the world, where the young lava flows prompted us to talk about geology. These volcanoes are formed by the accumulation of magma (molten rock that forms below the earth’s surface). Magma can erupt through one or more volcanic vents, which can be a single opening, a cluster of openings, or a long crack, called fissure vent. It forms deep within the earth, generally within the upper part of the mantle (one of the layers of the earth’s crust) or, less commonly, within the base of the earth’s crust. High temperatures and pressures are needed to form magma.
Lava is magma that breaks the surface and erupts from a volcano. If the lava is very fluid, it flows rapidly down the volcano’s slopes. Lava that is more sticky and less fluid moves slower. Lava flows that have a continuous, smooth, ropy or billowy surface are called pahoe-hoe flows, while aa flows have a jagged surface composed of loose, irregularly shaped lava chunks. Once cooled, pahoe-hoe forms smooth rocks, while aa forms jagged rocks. The words pahoe-hoe and aa are Hawaiian terms that describe the texture of the lava.
Today we visited Isabela and Fernandina, the youngest islands in Galapagos, located on the western side of the archipelago. This area is also the richest area due to the upwelling and the quantity of food and plankton that animals can find here. This morning we took Zodiac cruises along the coastline of a collapsed volcano, where highlights included a small pod of bottle-nosed dolphins swimming alongside us. This was followed by a snorkeling outing in the same area, where we had the chance to swim among different kinds of tropical fish, sea lions, sea turtles, a devil manta ray, golden rays and even the elusive oceanic sun fish (Mola mola): it was truly incredible.
During the afternoon we sailed along the coastline and observed the active volcanoes that form these two islands. We proceeded to disembark on Fernandina, the most pristine island in the world, where the young lava flows prompted us to talk about geology. These volcanoes are formed by the accumulation of magma (molten rock that forms below the earth’s surface). Magma can erupt through one or more volcanic vents, which can be a single opening, a cluster of openings, or a long crack, called fissure vent. It forms deep within the earth, generally within the upper part of the mantle (one of the layers of the earth’s crust) or, less commonly, within the base of the earth’s crust. High temperatures and pressures are needed to form magma.
Lava is magma that breaks the surface and erupts from a volcano. If the lava is very fluid, it flows rapidly down the volcano’s slopes. Lava that is more sticky and less fluid moves slower. Lava flows that have a continuous, smooth, ropy or billowy surface are called pahoe-hoe flows, while aa flows have a jagged surface composed of loose, irregularly shaped lava chunks. Once cooled, pahoe-hoe forms smooth rocks, while aa forms jagged rocks. The words pahoe-hoe and aa are Hawaiian terms that describe the texture of the lava.
