A caldera is a large, bowl-shaped depression that forms following a volcanic eruption when the magma chamber underneath a volcano is emptied, causing the overlying rock to collapse. Calderas can range in size from a few kilometers to tens of kilometers in diameter and are often filled with water, forming a volcanic crater lake.
Formation of Calderas
Calderas are formed through a sequence of events during a volcanic eruption:
Volcanic Eruption: During a volcanic eruption, magma is expelled from the volcano, leading to a reduction in the pressure inside the magma chamber.
Magma Chamber Emptying: As the magma is expelled, the roof of the magma chamber loses support, causing it to collapse.
Caldera Formation: The collapse of the roof of the magma chamber creates a large depression known as a caldera.
Types of Calderas
There are several types of calderas, including:
Explosion Calderas: Formed by the violent ejection of magma during a volcanic eruption, often leaving a large, circular depression.
Subsidence Calderas: Formed by the gradual sinking of the ground as magma is removed from the magma chamber, often resulting in a more irregular-shaped depression.
Resurgent Calderas: Formed by the resurgence of magma into the emptying magma chamber, leading to uplift and the formation of a central peak within the caldera.
Study Guide for Calderas
To study calderas, it's important to understand the following key concepts:
Describe the process of caldera formation during a volcanic eruption.
Explain the differences between explosion, subsidence, and resurgent calderas.
Identify and analyze specific examples of calderas around the world, including their size, shape, and formation history.
By mastering these concepts, you can develop a comprehensive understanding of calderas and their significance in the study of volcanic processes and geological formations.
Create a computational model to calculate the change in the energy of one component in a system when the change in energy of the other component(s) and energy flows in and out of the system are known.
Develop and use models to illustrate that energy at the macroscopic scale can be accounted for as either motions of particles or energy stored in fields.