Tutuila
Tuff cone(s) in United States
Key Facts
Elevation
653 m (2,142 ft)
Type
Tuff cone(s)
Location
-14.290°, -170.702°
Region
Samoan Hotspot Volcano Group
Rock Type
Basalt / Picro-Basalt
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
The elongated, extensively eroded Tutuila Island in the center of the Samoan Islands consists of five Pliocene-to-Pleistocene volcanoes constructed along two or three rifts trending SSW-NNE. The Pago basaltic-to-andesitic shield volcano in the center of the 32-km-long island is truncated by an eroded, 9-km-wide caldera that encloses Pago Pago harbor on its west. The caldera is now partially filled by cinder cones and trachytic lava domes.
ENE-trending dike complexes are prominently exposed on Pago volcano. Following a lengthy period of erosion, submergence, and the construction of a barrier reef, the Leone Volcanics were erupted during the Holocene along a 5-km-long N-S-trending fissure over a broad area at the southernmost part of the island (Stearns, 1944), forming a group of initially submarine tuff cones and subsequent subaerial cinder cones that produced fresh-looking pahoehoe lava flows. An ash layer overlying a cultural deposit in the SW part of the island was radiocarbon dated at about 440 +/- 200 CE (Addison et al.
, 2006).
Volcanic Hazards & Risk Assessment
Primary Hazards
Risk Level
Geological Composition & Structure
Rock Types
Tectonic Setting
Age & Formation
Eruption Statistics & Analysis
| Metric | Value | Global Ranking | Significance |
|---|---|---|---|
| Total Recorded Eruptions | Unknown | Low | Moderately active volcano |
| Maximum VEI | VEI Unknown | Minor | Local impact potential |
| Recent Activity | 1586 years ago | Historical | Historically active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Southern Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 244020
- •Evidence: Eruption Dated
- •Epoch: Holocene
About the Photo
Cliffs and an offshore island mark the rugged coastline of Tutuila Island. The elongated, extensively eroded Tutuila in the center of the Samoan Islands consists of five Pliocene-to-Pleistocene volcanoes constructed along rifts trending SSW-NNE. Following a lengthy period of erosion, submergence, and the construction of a barrier reef, the Leone volcanics were erupted during the Holocene along a 5-km-long N-S-trending fissure, forming a group of scoria cones that produced pahoehoe lava flows.
Photo by Tavita Togia, 2004 (U. S. National Park Service).
Authority Sources
Related Volcanoes
Basic Information
This page shows basic data from the Smithsonian Global Volcanism Program. For more detailed information, visit the official Smithsonian page.