Mantle Xenoliths from Southeastern New England

  1. F.R. Boyd and
  2. Henry O.A. Meyer
  1. Brian D. Leavy and
  2. O. Don Hermes

Published Online: 19 MAR 2013

DOI: 10.1029/SP016p0374

The Mantle Sample: Inclusion in Kimberlites and Other Volcanics

The Mantle Sample: Inclusion in Kimberlites and Other Volcanics

How to Cite

Leavy, B. D. and Hermes, O. D. (1979) Mantle Xenoliths from Southeastern New England, in The Mantle Sample: Inclusion in Kimberlites and Other Volcanics (eds F.R. Boyd and H. O.A. Meyer), American Geophysical Union, Washington, D.C.. doi: 10.1029/SP016p0374

Author Information

  1. Department of Geology, University of Rhode Island, Kingston, Rhode Island

Publication History

  1. Published Online: 19 MAR 2013
  2. Published Print: 1 JAN 1979

ISBN Information

Print ISBN: 9780875902135

Online ISBN: 9781118664858

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Keywords:

  • Crustal xenoliths and xenocrysts;
  • Host dikes;
  • Megacrysts;
  • Mineral chemistry;
  • Ultramafic xenoliths;
  • Whole-rock chemistry

Summary

Newly exposed mafic dikes that intrude granites in southwestern Rhode Island (USA) contain a suite of ultramafic xenoliths and megacrysts. This is the first reported occurrence of nodule-bearing rocks from southeastern New England. Ultramafic xenoliths in these dikes include spinel lherzolite, spinel harzburgite, and wehrlite. These have been mechanically transported upward in a lamprophyric matrix which crystallized relatively rapidly.

The mineral assemblages, textures, major element abundances, and mineral chemistry exhibited by these nodules indicate that they were derived from the upper mantle. Coincidence of the orientation of the Westerly dikes with Mesozoic lamprophyres in central New England suggests that the genesis of the host dikes and the mobilization of the included xenoliths was related to a major tectonic event which affected this part of New England during the post-Paleozoic.