|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
This site is maintained by the MARGINS Office. Please share your comments and suggestions with us.
|
|
|
Browse MARGINS-related
awards in reverse chronological order after start
date (most recent first):
|
|
|
 |
Collaborative Research: Resolving Mantle, Crustal and
Slab Fluxes to Arc Magmatism in Central America Using Geothermal Fluids
and Volcanic Rocks
| MARGINS Focus Area |
Subduction Factory |
| NSF Org |
EAR |
| Latest Amendment Date |
December 27, 2000 |
| Award Number |
0003628 |
| Award Instrument |
Standard Grant |
| Program Manager |
Glen S. Mattioli
EAR DIVISION OF EARTH SCIENCES
GEO DIRECTORATE FOR GEOSCIENCES |
| Start Date |
January 15, 2001 |
| Expires |
December 31, 2003 (Estimated) |
| Expected Total Amount |
$180,933 (Estimated) |
| Investigator |
David R. Hilton (Principal
Investigator current) |
| Sponsor |
U of Cal SD Scripps Inst
9500 Gilman Drive
La Jolla, CA 92093 |
| NSF Program |
1573 PETROLOGY AND GEOCHEMISTRY |
| Field Application |
0000099 Other Applications NEC |
| Abstract |
This proposal is aimed at producing a volatile mass balance
for the Central American subduction zone by quantifying the contributions
from the subducting slab, mantle wedge and overlying crust to
the overall arc budget. The Central American arc was chosen because
it possess a number of unique features which allow explicit linkages
to be forged between systematic variations in volcanic output
and variations in subduction parameters, specifically slab dip,
sediment supply and crustal thickness. Our approach is to couple
CO2 and helium measurements (isotopes and relative abundances)
which allows for identification and quantitative assessment of
the various contributors to the magmatic output. Although a powerful
technique, the accuracy of any flux estimates is limited by uncertainties
in the effects of magmatic degassing on resultant CO2/3He ratios
and on assumptions on the isotopic and abundance characteristics
assigned to potential endmember compositions involved in arc magmagenesis.
By analyzing and comparing the CO2-He relationships in geothermal
fluids with mafic minerals both along and across the Central America
arc, we aim to explore the extent of these limitations and to
assess approaches with the potential to circumvent any difficulties.
Additionally, we will derive present-day CO2 fluxes through combined
COSPEC and gas chemistry studies. This offers the further possibility
of deriving absolute fluxes for N2 and H2O and for also constraining
their provenance in the subduction zone factory. |
|
