Rincon de la Vieja

Geography & Climate

Rincon de la Vieja is located in Costa Rica, within the Central America Volcanic Arc of the broader Middle America-Caribbean Volcanic Regions. Situated at 10.83° N, 85.34° W in the Northern Hemisphere, the volcano lies within a tropical climate zone. With a summit elevation of 1,729 meters above sea level, Rincon de la Vieja is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Rincon de la Vieja sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Costa Rica near Rincon de la Vieja, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is andesite / basaltic andesite, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

Eruption History Summary

Rincon de la Vieja has 34 recorded eruptions in the geological database, spanning from 1820 BCE to 2024 CE. The most powerful recorded event was a cataclysmic eruption with ash columns reaching the stratosphere in 1820 BCE, reaching VEI 4 on the Volcanic Explosivity Index. Notable eruptions include 1966 CE (VEI 3), 1912 CE (VEI 3), 1820 BCE (VEI 4). With an average interval of roughly 113 years between eruptions over a span of 3,841 years, this is one of the more frequently active volcanoes in the database. This persistent activity suggests a robust and well-supplied magma system beneath the volcano. With eruptive activity as recently as 2024 CE, Rincon de la Vieja remains an actively monitored volcano.

Significance

With a maximum recorded VEI of 4, Rincon de la Vieja has demonstrated the capacity for significant explosive eruptions that can impact regional aviation, agriculture, and communities tens of kilometers from the summit. VEI 4 eruptions produce ash columns reaching 15-25 kilometers into the atmosphere. Its 34 recorded eruptions make it one of the most prolific volcanoes in our database, reflecting a persistent and well-documented eruptive history that has provided volcanologists with extensive data for understanding eruption patterns and forecasting future activity. Given its recent activity, Rincon de la Vieja is closely monitored by geological survey organizations to provide early warning of future unrest.

GVP Reference Summary

Rincón de la Vieja is a volcanic complex in the Guanacaste Range of NW Costa Rica. Sometimes referred to as the Rincon de la Vieja-Santa María Volcanic Complex, it consists of a slightly arcuate 20-km-long ridge of 12 craters and pyroclastic cones constructed within the 15-km-wide early Pleistocene Guachipelín caldera, whose rim is exposed on the south side. Sometimes known as the "Colossus of Guanacaste," it has an estimated volume of 130 km3 and contains at least nine major eruptive centers. The Santa María cone, the highest peak of the complex, is located on the E side of the ridge and has a lake within the 400-m-diameter crater. A Plinian eruption producing the 0.25 km3 Río Blanca tephra about 3,500 years ago was the last major magmatic eruption. All subsequent eruptions, including numerous reported eruptions possibly dating back to the 16th century, have been from the active crater, near the center of the complex, with an acidic 300-m-diameter lake.

— Smithsonian Institution, Global Volcanism Program