Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics.
We investigate the igneous and mantle dynamic processes of mantle plume midocean ridge interaction with geophysical observational and numerical modeling studies. Bathymetric and gravity anomalies along seafloor isochrons are examined at the Galapagos, Iceland, Azores, Tristan, and Easter plume ridge...
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ftdtic:ADA325948 2023-05-15T16:46:15+02:00 Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. Ito, Garrett T. MASSACHUSETTS INST OF TECH CAMBRIDGE 1996-09 text/html http://www.dtic.mil/docs/citations/ADA325948 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA325948 en eng http://www.dtic.mil/docs/citations/ADA325948 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Physical and Dynamic Oceanography Geology Geochemistry and Mineralogy *HOT SPOTS *GEOPHYSICS *GEOCHEMISTRY *OCEAN RIDGES *VOLCANISM MATHEMATICAL MODELS INTERACTIONS FLUX(RATE) THESES THREE DIMENSIONAL BATHYMETRY MIGRATION FLOW PLUMES VISCOSITY AZORES EARTH MANTLE GRAVITY ANOMALIES ICELAND IGNEOUS ROCK *MID OCEAN RIDGES Text 1996 ftdtic 2016-02-19T20:17:43Z We investigate the igneous and mantle dynamic processes of mantle plume midocean ridge interaction with geophysical observational and numerical modeling studies. Bathymetric and gravity anomalies along seafloor isochrons are examined at the Galapagos, Iceland, Azores, Tristan, and Easter plume ridge systems. Anomaly amplitudes decrease with increasing plume ridge distance whereas along-isochron widths decrease with increasing spreading rate. Three dimensional numerical models predict that along-axis plume width increases with plume volume flux but decreases with increasing spreading rate and plume ridge distance. Ridge migration is predicted to inhibit plume ridge interaction when ridges migrate toward plumes and enhance interaction when ridges migrate away from the plumes. The effects of decompression melting on plume density and viscosity do not appreciably affect the broad scale flow of the plume, but they do contribute significantly to predicted geophysical anomalies. Numerical models predict successfully the geophysical observations at the Iceland-Mid-Atlantic Ridge and Galapagos plume ridge systems. Predictions of geochemistry suggest that mixing between the plumes and ambient mantle most likely occurs below the asthenosphere. Models of the Iceland plume require substantial along-axis melt migration in order to explain a variety of geophysical and geochemical observations. Text Iceland Defense Technical Information Center: DTIC Technical Reports database Galapagos Mid-Atlantic Ridge Tristan ENVELOPE(140.900,140.900,-66.735,-66.735) |
institution |
Open Polar |
collection |
Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
Physical and Dynamic Oceanography Geology Geochemistry and Mineralogy *HOT SPOTS *GEOPHYSICS *GEOCHEMISTRY *OCEAN RIDGES *VOLCANISM MATHEMATICAL MODELS INTERACTIONS FLUX(RATE) THESES THREE DIMENSIONAL BATHYMETRY MIGRATION FLOW PLUMES VISCOSITY AZORES EARTH MANTLE GRAVITY ANOMALIES ICELAND IGNEOUS ROCK *MID OCEAN RIDGES |
spellingShingle |
Physical and Dynamic Oceanography Geology Geochemistry and Mineralogy *HOT SPOTS *GEOPHYSICS *GEOCHEMISTRY *OCEAN RIDGES *VOLCANISM MATHEMATICAL MODELS INTERACTIONS FLUX(RATE) THESES THREE DIMENSIONAL BATHYMETRY MIGRATION FLOW PLUMES VISCOSITY AZORES EARTH MANTLE GRAVITY ANOMALIES ICELAND IGNEOUS ROCK *MID OCEAN RIDGES Ito, Garrett T. Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. |
topic_facet |
Physical and Dynamic Oceanography Geology Geochemistry and Mineralogy *HOT SPOTS *GEOPHYSICS *GEOCHEMISTRY *OCEAN RIDGES *VOLCANISM MATHEMATICAL MODELS INTERACTIONS FLUX(RATE) THESES THREE DIMENSIONAL BATHYMETRY MIGRATION FLOW PLUMES VISCOSITY AZORES EARTH MANTLE GRAVITY ANOMALIES ICELAND IGNEOUS ROCK *MID OCEAN RIDGES |
description |
We investigate the igneous and mantle dynamic processes of mantle plume midocean ridge interaction with geophysical observational and numerical modeling studies. Bathymetric and gravity anomalies along seafloor isochrons are examined at the Galapagos, Iceland, Azores, Tristan, and Easter plume ridge systems. Anomaly amplitudes decrease with increasing plume ridge distance whereas along-isochron widths decrease with increasing spreading rate. Three dimensional numerical models predict that along-axis plume width increases with plume volume flux but decreases with increasing spreading rate and plume ridge distance. Ridge migration is predicted to inhibit plume ridge interaction when ridges migrate toward plumes and enhance interaction when ridges migrate away from the plumes. The effects of decompression melting on plume density and viscosity do not appreciably affect the broad scale flow of the plume, but they do contribute significantly to predicted geophysical anomalies. Numerical models predict successfully the geophysical observations at the Iceland-Mid-Atlantic Ridge and Galapagos plume ridge systems. Predictions of geochemistry suggest that mixing between the plumes and ambient mantle most likely occurs below the asthenosphere. Models of the Iceland plume require substantial along-axis melt migration in order to explain a variety of geophysical and geochemical observations. |
author2 |
MASSACHUSETTS INST OF TECH CAMBRIDGE |
format |
Text |
author |
Ito, Garrett T. |
author_facet |
Ito, Garrett T. |
author_sort |
Ito, Garrett T. |
title |
Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. |
title_short |
Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. |
title_full |
Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. |
title_fullStr |
Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. |
title_full_unstemmed |
Mantle Plume-Midocean Ridge Interaction: Geophysical Observations and Mantle Dynamics. |
title_sort |
mantle plume-midocean ridge interaction: geophysical observations and mantle dynamics. |
publishDate |
1996 |
url |
http://www.dtic.mil/docs/citations/ADA325948 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA325948 |
long_lat |
ENVELOPE(140.900,140.900,-66.735,-66.735) |
geographic |
Galapagos Mid-Atlantic Ridge Tristan |
geographic_facet |
Galapagos Mid-Atlantic Ridge Tristan |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA325948 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766036356659675136 |