Tracking the magmatic evolution of island arc volcanism: Insights from a high-precision Pb isotope record of Montserrat, Lesser Antilles

M. Cassidy*, R. N. Taylor, M. R. Palmer, R. J. Cooper, C. Stenlake, J. Trofimovs

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

30 Citations (Scopus)


The volcanic succession on Montserrat provides an opportunity to examine the magmatic evolution of island arc volcanism over a ∼2.5 Ma period, extending from the andesites of the Silver Hills center, to the currently active Soufrire Hills volcano (February 2010). Here we present high-precision double-spike Pb isotope data, combined with trace element and Sr-Nd isotope data throughout this period of Montserrat's volcanic evolution. We demonstrate that each volcanic center; South Soufrire Hills, Soufrire Hills, Centre Hills and Silver Hills, can be clearly discriminated using trace element and isotopic parameters. Variations in these parameters suggest there have been systematic and episodic changes in the subduction input. The SSH center, in particular, has a greater slab fluid signature, as indicated by low Ce/Pb, but less sediment addition than the other volcanic centers, which have higher Th/Ce. Pb isotope data from Montserrat fall along two trends, the Silver Hills, Centre Hills and Soufrire Hills lie on a general trend of the Lesser Antilles volcanics, whereas SSH volcanics define a separate trend. The Soufrire Hills and SSH volcanic centers were erupted at approximately the same time, but retain distinctive isotopic signatures, suggesting that the SSH magmas have a different source to the other volcanic centers. We hypothesize that this rapid magmatic source change is controlled by the regional transtensional regime, which allowed the SSH magma to be extracted from a shallower source. The Pb isotopes indicate an interplay between subduction derived components and a MORB-like mantle wedge influenced by a Galapagos plume-like source.

Original languageEnglish
Article numberQ05003
JournalGeochemistry, Geophysics, Geosystems
Issue number5
Publication statusPublished - 1 May 2012


  • Galapagos plume
  • island arc
  • Lesser Antilles
  • Montserrat
  • Pb isotopes
  • subduction zone

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology


Dive into the research topics of 'Tracking the magmatic evolution of island arc volcanism: Insights from a high-precision Pb isotope record of Montserrat, Lesser Antilles'. Together they form a unique fingerprint.

Cite this