with Dr. Susanne Straub
Supported by NSF Grant EAR 18-36032
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1836032&HistoricalAwards=false
Earth is a dynamic planet that became and remained habitable through continuous exchange of materials between the Earth’s surface (crust, oceans and atmosphere, <100 km thick) and the ca. 2900 km thick mantle of the Earth that underlies the Earth’s continental and oceanic crust. Understanding the role of the fluxes, requires us to know how, and where, how much, and how fast material is exchanged. However, unlike the movement of air, water and surface rocks, material fluxes in the Earth’s interior cannot be observed directly, and can only be reconstructed indirectly by means by ‘geochemical tracers’. Such tracing is not unlike tracing the course of an underground river by putting dye in the water before it disappears in the ground.
In this talk, I will present our research progress with respect to using the capricious and elusive cosmogenic 10Be as tracer to understand which deep Earth material fluxes fuel the highly explosive arc volcanoes.
Introductory slide show (pptx) (pdf)
This program is part of a series of E2C presentations by Susanne Straub:
“Testing the Slab Connection in the Transmexican Volcanic Belt” (Nov 2019)
NSF-project: Collaborative Research: Testing Source vs. Crustal Processing in High-Mg# Arc Magmas by Os-O-He-Olivine Systematics with Suzanne Straub
E2C-Title: Why are Arc Magmas so Rich in Silica?
Magmas that are rich in silica- and volatiles (H2O, CO2, S) produce the most explosive eruptions on Earth. Most of these magmas erupt in volcanic arcs, which are chains of volcanoes that are strung along continental and ocean plate boundaries, such as for example the ‘Ring of Fire’ around the Pacific ocean. While there is wide agreement that the volatiles originate from the root regions of arc volcanoes deep in the Earth’s mantle, the origin of the silica is far less clear. Is the high silica content also a feature of the mantle source, or is it acquired only after melt formation during ascent in the crustal basement, which all arc magmas must pass? In the project we investigate this question through the composition of tiny olivine crystals that grow abundantly in the arc magmas from the Trans-Mexican Volcanic Belt.
Is there a link between explosive volcanism and the Earth’s climate? (Dec 2020)
A RELATED E2C program:
“How Have Glaciers Behaved in Patagonia in the Past?” with Michael Kaplan (Oct 2014)
provides more information about hos Beryllium-10 dating works.
ADDITIONAL RESOURCES
Beryllium dating
Geochemical tracers
Crustal thickness controlled by plate tectonics: A review of crust–mantle interaction processes illustrated by European examples
Cosmogenic nuclides
Applications of cosmogenic 10-Be to problems in the Earth Sciences (37 pp.)