Gran Canaria Volcano | John Seach

john

Canary Islands, Spain

28.00 N, 15.58 W
summit elevation 1950 m
Fissure vents

Gran Canaria is located in the middle of the Canary archipelago, 220 km off the cost of Western Saraha. Africa. It forms the third largest of the Canary Islands. The volcano contains scoria cones and lava flows.

Formation of the Island
The island has formed in three stages.

Stage 1 consisted of formation of a basaltic
shield volcano probably located off the west coast of the island. This was followed by formation ofa collapse caldera 15-20 km in diameter now located in the center of the island.

Stage 2 corresponds to the Roque Nublo Formation, which includes lava flows and pyroclastic deposits erupted from a stratocone near the center of the present island that may have reached a height of at least 2500 m.

Stage 3 is characterized by the eruption of nephelinites and basanites from small vents dispersed in the center and the northeastern half of the island.

Large volcanic debris avalanche
During the second magmatic phase of evolution of Gran Canaria island, there was a large gravitational sector collapse at the volcano. This formed Roque Nublo Debris Avalanche Deposit. The debris avalanche was 3-4 cubic km in volume, and reaching a distance of 28-30 km.

The avalanche deposits contains megablocks, some over 500 m in diameter, which
exceeds the maximum size recorded for dry avalanche deposit megablocks. The avalanche moved very quickly (average speed: 90 m/s, with a total travel time about 5 minutes).

Further reading
Rodriguez‐Gonzalez, Alejandro, et al. "The Holocene volcanic history of Gran Canaria island: implications for volcanic hazards." Journal of Quaternary Science: Published for the Quaternary Research Association 24.7 (2009): 697-709.

Guillou, Hervé, et al. "The Plio–Quaternary volcanic evolution of Gran Canaria based on new K–Ar ages and magnetostratigraphy." Journal of Volcanology and Geothermal Research 135.3 (2004): 221-246.

Gran Canaria Volcano Eruptions

~20 BC