The summit of Kilauea Volcano is dominated by faults and fault-bounded blocks related to the formation of its caldera (dark arcuate lines that define a broad oval-shaped depression). The faults formed when the summit sunk (collapsed) into voids left when magma moved outward into the volcano's rift zones. Additional collapse features -- pit craters -- can be seen on the southwest caldera floor at Halemau`ma`u (round crater 1 km diameter), on the eastern edge of the caldera at Kilauea Iki, and in the southeast part of the caldera at Keanakako`i Crater.
On the east edge of the caldera is a broad lava shield, known as `Aila`au, that includes the east portion of Kilauea Iki and two small pit craters. The `Aila`au shield was active 350-400 years ago, and lava flows erupted from it paved extensive areas of Kilauea's surface north of the east rift zone all the way to the sea. The broad shallow sag atop `Aila`au may overlie a buried pit crater.
The lower southeast flank of Mauna Loa volcano is barely visible in the upper left of the map (slightly darker area).
The shaded-relief map represents a portion of the Digital Elevation Model (1:250,000 scale) for the Big Island of Hawai`i. See access to the DEM file and a user guide.