Laguna Colorada (caldera)

Laguna Colorada is an ignimbrite shield[1] of the Altiplano-Puna volcanic complex[2] at an altitude of 5,000 metres (16,000 ft)[3] in Bolivia.[4]

Laguna Colorada is a c. 40 kilometres (25 mi) wide ignimbrite shield that was formerly also known as Panizos (not to be confused with Cerro Panizos. The shield is not clearly associated with a caldera but appears to contain a sag structure.[1] The ignimbrite field is bordered by the Laguna Colorada to the west, Cerro Torque in the north and Quetena to the east;[4] Laguna Colorada is also the origin of the name of the shield.[1] Likewise, the "Tatio formation" at El Tatio originates from eruptions at Laguna Colorada;[5] the 700,000 years old Tatio ignimbrite however is considered to be separate.[1] An older ignimbrite was erupted 2.21±0.05 million years ago.[6]

An ignimbrite is associated with Laguna Colorada. This ignimbrite was erupted 1.98 million years ago and has a volume of 60 cubic kilometres (14 cu mi) dense rock equivalent,[3] covering a surface of about 1,100 square kilometres (420 sq mi). Several fall deposits occur both within and below the ignimbrite.[1] This ignimbrite is also known as the Tatio ignimbrite and given a volume of 150 cubic kilometres (36 cu mi) dense rock equivalent,[7] or the Aguadita tuffs.[1] The ignimbrite is one of the youngest in the region and keeps a noticeable texture in high altitude images.[4]

The active geothermal fields of El Tatio and Sol de Manana are located around the Laguna Colorada system.[8] An electrical conductivity anomaly beneath Laguna Colorada has been interpreted either as new magma or hydrothermally altered material.[9] Recent satellite imagery has shown that Laguna Colorada is subsiding at a rate of 4 millimetres per year (0.16 in/year), with the subsidence encompassing the area of the Laguna Colorada ignimbrite and covering a diameter of 20 kilometres (12 mi).[3]