Skip Links

Geologic Investigations Series I-2614

About USGS /  Science Topics /  Maps, Products & Publications /  Education / Publication: FAQ

Geologic Map of the Middle East Rift Geothermal Subzone, Kīlauea Volcano, Hawaiʻi

By Frank A. Trusdell and Richard B. Moore

Link to map PDF (682 KB)Download Publication
Map PDF (682 KB)
Right-Click to 'Save As' or 'Download'

Kīlauea is an active shield volcano in the southeastern part of the Island of Hawaiʻi. The middle east rift zone (MERZ) map includes about 27 square kilometers of the MERZ and shows the distribution of the products of 37 separate eruptions during late Holocene time. Lava flows erupted during 1983–96 have reached the mapped area. The subaerial part of the MERZ is 3–4 km wide and about 18 km long. It is a constructional ridge, 50–150 m above the adjoining terrain, marked by low spatter ramparts and cones as high as 60 m. Lava typically flowed either northeast or southeast, depending on vent location relative to the topographic crest of the rift zone. The MERZ receives more than 100 in. of rainfall annually and is covered by tropical rain forest. Vegetation begins to grow on lava a few months after its eruption. Relative heights of trees can be a guide to relative ages of underlying lava flows, but proximity to faults, presence of easily weathered cinders, and human activity also affect the rate of growth. The rocks have been grouped into five basic age groups. The framework for the ages assigned is provided by eight radiocarbon ages from previous mapping by the authors and a single date from the current mapping effort. The numerical ages are supplemented by observations of stratigraphic relations, degree of weathering, soil development, and vegetative cover.

The database for this map may be found at

Version 1.0

Posted November 2006

ArcView shapefiles and other related database files.

Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Acrobat Reader or similar software is required to view it. Download the latest version of Acrobat Reader, free of charge or go to for free tools that allow visually impaired users to read PDF files. logo