21 March, 2012 – Seminar
When: 4pm on Wednesday, March 21st, 2012
Where: DIAS, Geophysics Section, 5 Merrion Square, Dublin 2, (library)
Speaker: Dr. Fabrice Gaillard from Institut des Sciences de la Terre d’Orleans
Title: Partial melting and electrical conductivity of the mantle.
Abstract:
The identification of highly conductive regions in the Earth’s mantle has long been intriguing for the Geosciences community because peridotite rocks are not conductive. Supplementary materials must be added to ordinary peridotite in order to make the mantle conductive and mineral physicists, petrologists, geochemists and geophysicists have different point of views concerning the nature of this conductive component. A long standing interpretation has been water and its incorporation as impurities in mantle minerals such as olivine. The possibility of correlating high conductivity with high mantle water content has considerably impacted the scientific literature but disappointingly, most recent experimental constraints refute this elegant model. The ancient petrological model of mantle melting has recently been re-adopted with, as added value, the role of volatiles (H-C-Cl-F) on mantle melting. Several points will be tackled in this talk. Can volatiles allow mantle melting in the entire upper (and lower) mantle? What sort of melts is then produced? How they may deviate from the standard basaltic compositions? What is their impact on mantle conductivity? Can we recognize these melts in electromagnetic images of mantle conductivity? Can we then correlate electrical heterogeneity to chemical heterogeneities, ie. volatiles, redox,… ? Inbrief, can we reconcile the petrological mantle with the electrical mantle?
Leave a Comment
Last Updated: 22nd March 2016 by Anna
2012-03-21 – Seminar: Dr. Fabrice Gaillard
21 March, 2012 – Seminar
When: 4pm on Wednesday, March 21st, 2012
Where: DIAS, Geophysics Section, 5 Merrion Square, Dublin 2, (library)
Speaker: Dr. Fabrice Gaillard from Institut des Sciences de la Terre d’Orleans
Title: Partial melting and electrical conductivity of the mantle.
Abstract:
The identification of highly conductive regions in the Earth’s mantle has long been intriguing for the Geosciences community because peridotite rocks are not conductive. Supplementary materials must be added to ordinary peridotite in order to make the mantle conductive and mineral physicists, petrologists, geochemists and geophysicists have different point of views concerning the nature of this conductive component. A long standing interpretation has been water and its incorporation as impurities in mantle minerals such as olivine. The possibility of correlating high conductivity with high mantle water content has considerably impacted the scientific literature but disappointingly, most recent experimental constraints refute this elegant model. The ancient petrological model of mantle melting has recently been re-adopted with, as added value, the role of volatiles (H-C-Cl-F) on mantle melting. Several points will be tackled in this talk. Can volatiles allow mantle melting in the entire upper (and lower) mantle? What sort of melts is then produced? How they may deviate from the standard basaltic compositions? What is their impact on mantle conductivity? Can we recognize these melts in electromagnetic images of mantle conductivity? Can we then correlate electrical heterogeneity to chemical heterogeneities, ie. volatiles, redox,… ? Inbrief, can we reconcile the petrological mantle with the electrical mantle?
Category: Geophysics Section News & Events
Meet the Judges of our "Reach for the Stars" Astrophotography competition! @petertgallagher is Head of @DIASAstronomy & has spent the past two decades studying the Sun its impacts on the Earth. To learn more and submit an entry see dias.ie/reachforthesta… #DIASdiscovers
She has over 15 years’ experience working in PR and communications and has wide-ranging experience of providing strategic communications support to organisations. Learn more about the competition and submit an entry 👉dias.ie/reachforthesta… #DIASdiscovers #astrophotography
Meet the Judges of our "Reach for the Stars" Astrophotography competition! @MartinaPQuinn is the Founder & Managing Director of @helloalicepr.
Want to learn more about what's happening on Mars? Check out our public lecture from November delivered Dr John Clinton and titled MarsQuakes! (5/5) youtu.be/_Lp0oLJ8Ahs
And then this Thursday @NASAMars Perseverance rover reaches Mars, which will try to land in a near equatorial crater called Jezero. Here you can see a possible route around the crater. (4/5)
Last Wednesday, the day the UAE revealed their first image of Mars, China's National Space Administration's Tianwen-1 arrived at Mars. This carries a rover which will be despatched to the surface in the coming months. (3/5) bbc.com/news/science-e…
First up is the @uaespaceagency's Hope mission entered orbit this day last week. It is the first inter-planetary mission by the UAE, and will stay in a wide orbit for one Martian year or two earth years to study climate and weather. (2/5)
It's a busy month over at our planetary neighbour Mars. Three missions headed there have or will enter orbit this month. Why so many at one time? They were timed to launch when the distance between the Earth and Mars was relatively short. (1/5)
#WomeninResearch
Looking for some #MondayMotivation? We are delighted to share this short video by @CClearych who is the O'Donovan Scholar at the School of Celtic Studies. Here she describes the amazing inputs of Eleanor Knott MRIA. youtu.be/Zfvw0KZbFTk @SCSLibrary @RIAdawson
Another addition to this DIAS managed online resource twitter.com/DIAS_ISOS/stat…