Widespread uplift and ‘trapdoor’ faulting on Galápagos volcanoes observed with radar interferometry

Falk Amelung (), Sigurjón Jónsson (), Howard Zebker and Paul Segall
Additional contact information
Falk Amelung: SOEST, University of Hawaii

Nature, 2000, vol. 407, issue 6807, 993-996

Abstract: Abstract Volcanic uplift, caused by the accumulation of magma in subsurface reservoirs, is a common precursor to eruptions1,2. But, for some volcanoes, uplift of metres or more has not yet led to an eruption3. Here we present displacement maps of volcanoes in the Galápagos Islands, constructed using satellite radar interferometry, that might help explain this dichotomy. We show that all but one of the seven volcanoes on the islands of Isabela and Fernandina deformed during 1992–99. Cerro Azul and Fernandina erupted4,5,6 during the observation period and show evidence of inflation, co-eruptive deflation and shallow dyke intrusion. In contrast, the largest volcano, Sierra Negra, has not erupted, yet exhibits spatially and temporally variable deformation, with a maximum uplift of 2.7 m between 1992 and 1999, which can be modelled by a shallow inflating sill. Inflation during 1997–98, however, was accompanied by ‘trapdoor’ faulting on a steeply dipping fracture system within the caldera. Repeated trapdoor faulting over geological time has formed an arcuate intra-caldera ridge within Sierra Negra and may have acted to relax stresses above the magma chamber, inhibiting summit eruptions. Similar processes may help explain large uplift unaccompanied by eruptive activity at other volcanoes.

Date: 2000
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/35039604 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:407:y:2000:i:6807:d:10.1038_35039604

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/35039604

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().