|Heiheiahulu marks the boundary between the middle and lower
parts of the east rift zone and is the most downrift shield in the rift
Hawaiian oral history suggests that the shield formed during the first half of the 18th
century. Early episodes of the eruption formed spatter ramparts along a
3.5-km-long segment of the rift zone and extruded extensive `a`a flows.
When activity became focused at Heiheiahulu, numerous lava flows built a shield,
and the larger ones moved south to the ocean between former Kaimu Bay (near
Kalapana) and Kehena. The Heiheiahulu shield (522 m) stands about 65
m above the surrounding ground and is topped by a crater less than 150 m
This aerial view of the Heiheiahulu shield looks directly east. Along the axis of the east rift zone, vents and lava flows of the 1955 eruption are visible in the distance. The prominent cones (upper left) are 3.2 km from the summit of Heiheiahulu; see photograph of one of the cones.
||This close aerial view of Heiheiahulu is toward the northwest. Typical of many basaltic shields and cones, the summit crater of Heiheiahulu is breached on one side (lower right). During the later stages of its eruption, lava poured through the breach to feed lava flows that spread southeast toward the ocean.|