This is another SIR-C radar image showing the southern part of Isla Isabela in the western Galapagos Islands. The image is centered at about 0.5 degree south latitude and 91 degrees west longitude and covers an area of 75 by 60 kilometers (47 by 37 miles). Alcedo is the volcano with bright (rough) lava flows on its flanks. The other volcano is Sierra Negra. The summit caldera of Alcedo is about 7.3 by 6.1 km wide - its is elliptical, not circular. Sierra Negra's caldera is bigger and more elongated: 9.0 by 7.2 km. Alcedo's caldera is about 260 m deep, but the bigger caldera is shallower - only 110 m deep.
Simplified from Jet Propulsion Lab press release P-43899, April 15, 1994.
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