The caldera complex at the peak of the volcano is made of at least six overlapping calderas and caldera segments (pictured).Mouginis-Mark, P.J. (1981). Late-stage Summit Activity of Martian Shield Volcanoes. Proc. 12th Lunar and Planetary Science Conference; Houston: LPI, 12B, pp. 1431–1447. Calderas are formed by roof collapse following depletion and withdrawal of the subsurface magma chamber after an eruption. Each caldera thus represents a separate pulse of volcanic activity on the mountain. The largest and oldest caldera segment appears to have formed as a single, large lava lake.Mouginis-Mark, P.J.; Harris, A.J.L.; Rowland, S.K. (2007). Terrestrial Analogs to the Calderas of the Tharsis Volcanoes on Mars in The Geology of Mars: Evidence from Earth-Based Analogs, M. Chapman, Ed.; Cambridge University Press: Cambridge, UK, p. 86 Using geometric relationships of caldera dimensions from laboratory models, scientists have estimated that the magma chamber associated with the largest caldera on Olympus Mons lies at a depth of about below the caldera floor.Beddingfield, C.B.; Burr, D.M. (2011). Formation and Evolution of Surface and Subsurface Structures within the Large Caldera of Olympus Mons, Mars. 42nd Lunar and Planetary Science Conference. LPI: Houston, TX, Abstract #2386. http://www.lpi.usra.edu/meetings/lpsc2011/pdf/2386.pdf Crater size-frequency distributions on the caldera floors indicate the calderas range in age from 350 Mya to about 150 Mya. All probably formed within 100 million years of each other.Robbins, S.J. et al. (2010). Dating The Most Recent Episodes of Volcanic Activity From Mars's Main Volcanic Calderae (sic). 41st Lunar and Planetary Science Conference, Abstract 2252. http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2252.pdf. It is possible that the magma chambers within Olympus Mons received new magma from the mantle after the caldera floors formed, leading to the inflation of each chamber and uplift of parts of the volcano summit.
The caldera complex at the peak of the volcano is made of at least six overlapping calderas and caldera segments (pictured).Mouginis-Mark, P.J. (1981). Late-stage Summit A,ctivity of Martian Shield Volcanoes. Proc. 12th Lunar and Planetary Science Conference; Houston: LPI, 12B, pp. 1431–1447. Calderas are formed by roof collapse following depletion and withdrawal of the subsurface magma chamber after an eruption. Each caldera thus represents a separate pulse of volcanic activity on the mountain. The largest and oldest caldera segment appears to have formed as a single, large lava lake.Mouginis-Mark, P.J.; Harris, A.J.L.; Rowland, S.K. (2007). Terrestrial Analogs to the Calderas of the Tharsis Volcanoes on Mars in The Geology of Mars: Evidence from Earth-Based Analogs M. Chapman, Ed.; Cambridge University Press: Cambridge, UK, p. 86 Using geometric relationships of caldera dimensions from laboratory models, scientists have estimated that the magma chamber associated with the largest caldera on Olympus Mons lies at a depth of about below the caldera floor.Beddingfield, C.B.; Burr, D.M. (2011). Formation and Evolution of Surface and Subsurface Structures within the Large Caldera of Olympus Mons, Mars. 42nd Lunar and Planetary Science Conference. LPI: Houston, TX, Abstract #2386. http://www.lpi.usra.edu/meetings/lpsc2011/pdf/2386.pdf Crater size-frequency distributions on the caldera floors indicate the calderas range in age from 350 Mya to about 150 Mya. All probably formed within 100 million years of each other.Robbins, S.J. et al. (2010). Dating The Most Recent Episodes of Volcanic Activity From Mars's Main Volcanic Calderae (sic). 41st Lunar and Planetary Science Conference, Abstract 2252. http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2252.pdf. It is possible that the magma chambers within Olympus Mons received new magma from the mantle after the caldera floors formed, leading to the inflation of each chamber and uplift of parts of the volcano summit.