PhD Research:
For my PhD dissertation, I have examined the behavior of noble gases and CO2 as mantle-derived volatiles are transferred to the hydrosphere and atmosphere via the different types of plate boundary: the Reykjanes Ridge (divergent), Central American Arc (convergent), and North Anatolian Fault Zone (strike-slip). In my dissertation, I discuss:
- The CO2-He-Ar systematics of basaltic glasses from the Reykjanes Ridge: Resolving volatile characteristics of mantle melts prior to degassing
- The He-CO2 isotope and relative abundance characteristics of geothermal fluids in El Salvador and Honduars: new constraints on volatile mass balance of the Central American Volcanic Arc
- Regional and temporal variations in CO2/3He, 3He/4He and δ13C along the North Anatolian Fault Zone, Turkey
The results of the El Salvador-Honduras project have been recently published (ref. below), and the results of the Reykjanes Ridge and North Anatolian Fault Zone projects are currently being prepared for publication. During the course of my PhD, I have presented preliminary results of each of the three projects at geological conferences (ref. below).
Abstracts of publications and meetings:
De Leeuw, G.A.M., Hilton, D.R., Fischer, T.P., Walker, J.A., 2007: The He-CO2 isotope and relative abundance characteristics of geothermal fluids in El Salvador and Honduras: New constraints on volatile mass balance of the Central American Volcanic Arc. Earth and Planetary Science Letters, 258, 132-146 Abstract
De Leeuw, G.A.M., Hilton, D.R., Murton, B.J., Taylor, R.N., 2006: Source mixing, degassing and crustal contamination of basaltic glasses along Reykjanes Ridge, AGU fall meeting, San Francisco Abstract
De Leeuw, G.A.M., Hilton, D.R., Fischer, T.P., Walker, J.A., 2005: Along and across-arc profiles in He-C systematics: new data from El Salvador and Honduras, Goldschmidt Conference, Moscow, Idaho Abstract
De Leeuw, G.A.M., Hilton., D.R., Güleç, N., Mutlu, H., 2004: He-C relationships in geothermal waters from the North Anatolian Fault Zone (NAFZ), Turkey, Goldschmidt Conference, Copenhagen, Denmark Abstract
De Leeuw, G.A.M., Hilton, D.R., Shaw, A.M., Murton, B.J., Taylor, R.N., 2002: Testing binary mixing models for lavas erupted along the Reykjanes Ridge; insights from C-He relationships, AGU fall meeting, San Francisco Abstract
MSc Research:
For my MSc thesis, I have examined rocks of various age, location and geologic setting to identify their origin and unravel more of their geologic history at:
- Pilbara Craton, Western Australia: geologic mapping and sampling of mafic and ultramafic igneous rocks of Archean age for microscopic and major and trace element analysis, preparation of the rock samples for XRF analysis, data interpretation and reportage of the geochemical analysis.
- La Palma, Canary Islands: mapping and sampling lava flows for mircroscopy and major and trace element analysis, preparation of the rock samples for XRF analysis, data interpretation and reportage of the geochemical analysis.
- Svecofennian orogen, South-eastern Sweden: mapping deformation structures of late Paleoproterozoic age, collecting samples for microscopic and geochemical analyses, computerizing the field-map, and mircroscopic analysis and reportage of the various deformation structures.
Abstract of conference presentation:
De Leeuw, G.A.M., Beintema, K.A., Wijbrans, J. R., White, S.H., 2001. Chemistry of Archaean gabbros intruding the Tabba Tabba shear zone, Pilbara, WA, 4IAS. AGSO, Record 2001/37, Perth, WA, pp. 143-145 Abstract