Magmatism and dynamics of continental breakup in the presence of a mantle plume
Thesis (Ph. D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), February 2000. Includes bibliographical references (p. 255-270). This thesis studies the dynamics of mantle melti...
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ftmit:oai:dspace.mit.edu:1721.1/55334 2023-06-11T04:12:22+02:00 Magmatism and dynamics of continental breakup in the presence of a mantle plume Korenaga, Jun, 1970- Thomas H. Jordan and Peter B. Kelemen. Woods Hole Oceanographic Institution. Joint Program in Oceanography Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences. Massachusetts Institute of Technology. Department of Ocean Engineering 2000 272 p. application/pdf http://hdl.handle.net/1721.1/55334 eng eng Massachusetts Institute of Technology http://hdl.handle.net/1721.1/55334 45302159 M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Joint Program in Oceanography Earth Atmospheric and Planetary Sciences Woods Hole Oceanographic Institution Thesis 2000 ftmit 2023-05-29T08:34:18Z Thesis (Ph. D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), February 2000. Includes bibliographical references (p. 255-270). This thesis studies the dynamics of mantle melting during continental breakups by geophysical, geochemical, and numerical analyses. The first part focuses on the mantle melting and crustal accretion processes during the formation of the Southeast Greenland margin, on the basis of deep-crustal seismic data. A new seismic tomographic method is developed to jointly invert refraction and reflection travel times for a compressional velocity structure, and a long-wavelength structure with strong lateral heterogeneity is successfully recovered, including 30- to 15-km-thick igneous crust within a 150-km-wide continent-ocean transition zone. A nonlinear Monte Carlo analysis is also conducted to establish the absolute uncertainty of model parameters. The derived crustal structure is first used to resolve the origin of a margin gravity high, with new inversion schemes using both seismic and gravity constraints. Density anomalies producing the gravity high seem to be confined within the upper crust, not in the lower crust as suggested for other volcanic margins. A new robust framework is then developed for the petrological interpretation of the velocity structure of igneous crust, and the thick igneous crust formed at the continentocean transition zone is suggested to have resulted from vigorous active upwelling of mantle with only somewhat elevated potential temperature. In the second part, the nature of mantle melting during the formation of the North Atlantic igneous province is studied on the basis of the major element chemistry of erupted lavas. A new fractionation correction scheme based on the Ni concentrations of mantle olivine is used to estimate primary melt compositions, which suggest that this province is characterized by a large degree of major element source ... Thesis Greenland North Atlantic DSpace@MIT (Massachusetts Institute of Technology) Greenland |
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English |
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Joint Program in Oceanography Earth Atmospheric and Planetary Sciences Woods Hole Oceanographic Institution |
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Joint Program in Oceanography Earth Atmospheric and Planetary Sciences Woods Hole Oceanographic Institution Korenaga, Jun, 1970- Magmatism and dynamics of continental breakup in the presence of a mantle plume |
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Joint Program in Oceanography Earth Atmospheric and Planetary Sciences Woods Hole Oceanographic Institution |
description |
Thesis (Ph. D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), February 2000. Includes bibliographical references (p. 255-270). This thesis studies the dynamics of mantle melting during continental breakups by geophysical, geochemical, and numerical analyses. The first part focuses on the mantle melting and crustal accretion processes during the formation of the Southeast Greenland margin, on the basis of deep-crustal seismic data. A new seismic tomographic method is developed to jointly invert refraction and reflection travel times for a compressional velocity structure, and a long-wavelength structure with strong lateral heterogeneity is successfully recovered, including 30- to 15-km-thick igneous crust within a 150-km-wide continent-ocean transition zone. A nonlinear Monte Carlo analysis is also conducted to establish the absolute uncertainty of model parameters. The derived crustal structure is first used to resolve the origin of a margin gravity high, with new inversion schemes using both seismic and gravity constraints. Density anomalies producing the gravity high seem to be confined within the upper crust, not in the lower crust as suggested for other volcanic margins. A new robust framework is then developed for the petrological interpretation of the velocity structure of igneous crust, and the thick igneous crust formed at the continentocean transition zone is suggested to have resulted from vigorous active upwelling of mantle with only somewhat elevated potential temperature. In the second part, the nature of mantle melting during the formation of the North Atlantic igneous province is studied on the basis of the major element chemistry of erupted lavas. A new fractionation correction scheme based on the Ni concentrations of mantle olivine is used to estimate primary melt compositions, which suggest that this province is characterized by a large degree of major element source ... |
author2 |
Thomas H. Jordan and Peter B. Kelemen. Woods Hole Oceanographic Institution. Joint Program in Oceanography Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences. Massachusetts Institute of Technology. Department of Ocean Engineering |
format |
Thesis |
author |
Korenaga, Jun, 1970- |
author_facet |
Korenaga, Jun, 1970- |
author_sort |
Korenaga, Jun, 1970- |
title |
Magmatism and dynamics of continental breakup in the presence of a mantle plume |
title_short |
Magmatism and dynamics of continental breakup in the presence of a mantle plume |
title_full |
Magmatism and dynamics of continental breakup in the presence of a mantle plume |
title_fullStr |
Magmatism and dynamics of continental breakup in the presence of a mantle plume |
title_full_unstemmed |
Magmatism and dynamics of continental breakup in the presence of a mantle plume |
title_sort |
magmatism and dynamics of continental breakup in the presence of a mantle plume |
publisher |
Massachusetts Institute of Technology |
publishDate |
2000 |
url |
http://hdl.handle.net/1721.1/55334 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland North Atlantic |
genre_facet |
Greenland North Atlantic |
op_relation |
http://hdl.handle.net/1721.1/55334 45302159 |
op_rights |
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 |
_version_ |
1768388149428355072 |