Caldera Lauca facts for kids
The Caldera Lauca is a huge, ancient caldera (which is like a giant bowl-shaped hollow in the ground, formed when a volcano collapses after a big eruption). You can find it in the Arica y Parinacota Region of Chile. It's located in the Cordillera Occidental, which is a mountain range. The caldera sits in the valley of the Lauca River.
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What is the Lauca Caldera Like?
This caldera is shaped like an oval. It stretches about 23 km from east to west and 50 km from north to south. Most of it is hidden under younger volcanic rocks. The northern part is covered by the Vilañuñumani-Tejene volcanic complex. The southern part ends near a place called Chucal.
How Old is the Lauca Caldera?
The Lauca Caldera is very old! It formed about 21 million years ago (mya). A huge eruption from this caldera created a type of rock called the Oxaya Ignimbrite. The eastern edge of the caldera is buried under even younger volcanic ash and rocks. However, we know it's located east of the Guallatiri volcano. The western edge of the caldera is marked by an Oligocene fault, which is a crack in the Earth's crust.
What is Inside the Caldera?
The caldera is filled with a thick layer of ignimbrite, which is a type of rock formed from hot volcanic ash and gas. This layer is up to 700 m thick and contains about 630 cubic km of ignimbrite. The rocks found here have different amounts of silicon dioxide (SiO2), ranging from 58% to 73%. Scientists have found one sample of Lauca ignimbrite that is actually younger than the caldera itself.
Other Volcanoes Nearby
The Lauca Caldera is one of the older volcanic areas in the Payachata region. Other old volcanic spots nearby include the Ajoya-Choquelimpie volcanic complex and the Caquena domes. In contrast, volcanoes like Pomerape and Parinacota are much younger volcanic centers in the same area.
See also
- Altiplano-Puna volcanic complex
- Lauca
- Guallatiri
