Historical information

When the ground depresses down at the point of a volcanic vent after a volcano’s magma chamber has been emptied it is known as a caldera, and not a volcano crater. (https://www.universetoday.com/31143/volcano-crater/, accessed 04 March 2019)

A caldera is a volcanic feature formed by the collapse of a volcano into itself, making it a large, special form of volcanic crater. A caldera collapse is usually triggered by the emptying of the magma chamber beneath the volcano, as the result of a large volcanic eruption.(https://www.sciencedaily.com/terms/caldera.htm)

Physical description

A volcanic vent, or depression on one side of Mount Franklin.