Please use this identifier to cite or link to this item:
http://hdl.handle.net/2122/1642
Authors: | Gregori, G. P.* Dong, W.* |
Title: | The correlation between geomagnetic field reversals, Hawaiian volcanism, and the motion of the Pacific plate | Issue Date: | Jan-1996 | Series/Report no.: | 1/39 (1996) | URI: | http://hdl.handle.net/2122/1642 | Keywords: | Geomagnetic reversals volcanism Hawaii's hot spot Pacific plate |
Subject Classification: | 04. Solid Earth::04.05. Geomagnetism::04.05.02. Geomagnetic field variations and reversals 04. Solid Earth::04.07. Tectonophysics::04.07.04. Plate boundaries, motion, and tectonics |
Abstract: | The correlation between geomagnetic field reversals and volcanism is investigated, according to the speculated consequence on volcanoes of the transient electric currents in the geodynamo, through Joule's heating, before and after every reversal event. We evaluate the temporal variation during the last ~ 70 Ma both of the magma emplacement rate Q(t) from the Hawaii hot spot, and of the speed v(t) of the Pacific plate, by means of the observed volumes of islands and seamounts along the Hawaii/Emperor Seamounts chain, and their respective radiometric datings. Results confirm expectations. A justification of the volcanic crises that lead to the generation of the large igneous provinces during the last ~ 250 Ma also emerged. We describe in detail the complex pattern of the timings of the different effects. Joule's power is generally responsible for ~ 75-80% of magmatism, and friction power only for ~ 20-25%; but, on some occasions almost ~ 100% is fuelled by friction alone. The visco-elastic coupling between lithosphere and asthenosphere results ~ 96% viscous, and ~ 4% elastic. |
Appears in Collections: | Annals of Geophysics |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
05 gregori.pdf | 4.2 MB | Adobe PDF | View/Open |
Page view(s)
151
checked on Mar 27, 2024
Download(s) 50
256
checked on Mar 27, 2024