School of Earth and Environment
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Jason Harvey Dr Jason Harvey

Research Fellow

Telephone number: +44(0) 113 34 35543
Email address: feejh@leeds.ac.uk
Room: 8.151

Biography

2010 to date: Research fellow in isotope geochemistry, University of Leeds

2009 to 2010: PDRA, The Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR), The Open University

2008 to date: Associate lecturer (Earth Sciences), The Open University.

2007 to 2009: Visiting researcher / Sessional lecturer, School of Earth & Planetary Sciences, Birckbeck College, University of London

2006 to 2007: Thermal ionisation mass spectrometry specialist, Boston University, Boston, MA, USA.

Qualifications

2005 PhD: "Messengers from the mantle: unravelling the effects of melt depletion and metasomatism in continental and oceanic peridotite using Re-Os isotopes

2001: BSc Hons (Dunelm) Geology, Durham University.

Memberships/Fellowships

Member of American Geophysical Union since 2004

Member of the Geochemistry Society since 2004

Elected Fellow of The Geological Society of London in 2005

Member of The Mineralogical Society of Great Britain and Ireland since 2011

Research Interests

My research focuses on chemical and isotopic heterogeneity in the mantle. In particular, I am interested in determining the magnitude and spatial distribution of such heterogeneities and determining the implications of these anomalous compositions in various tectonic settings.

I use a variety of isotope systems to investigate these problems and collaborate with a number of research groups in Europe and the US. My current research interests are relatively diverse but have a common peridotite theme:

  • Boron isotope fractionation during the high-pressure dehydration of antigorite serpentine. I am investigating the effects upon subduction of fluid flux to the overlying mantle wedge during the high-pressure, prograde reaction of antigorite-serpentinite (atg-serp) to chlorite-harzburgite (chl-harz). This research focuses upon the Cerro del Almirez massif in southern Spain - the only known outcrop in the world that preserves an atg-serp to chl-harz isograd in the field. During subduction the down-going, heavily serpentinited oceanic mantle first transforms from a lizardite-dominated serpentine to atg-serp, which is stable at higher P-T conditions, before the transformation, at 680 to 710oC and 1.6 to 1.9 GPa to chl-harz. This partial dehydration reaction fluxes B-bearing fluid from the dehydrating down-going slab into the hydrating overlying fore-arc mantle wedge, fractionating B isotopes with progressive dehydration and imparting distinctive isotopic signatures on both the down-going slab and overlying fore-arc. The continuing subduction of the still partially hydrated chlorite-bearing peridotite transports a low δ11B signature deeper into the convecting mantle while the fluid lost during the early stages of subduction primes the fore-arc peridotite with a distinctly high δ11B fluid. This fractionation of B isotopes thus produces isotopically variable B isotope reservoirs with which subsequent basaltic melts can interact and acquire their new B isotope fingerprint.

This work is funded by a research grant of £1590 from the Fearnesides Fund of The Geological Society of London and is being carried out in collaboration with Carlos Garrido (University of Granada), Samuele Agostini (IGG, CNR, Pisa), José-Alberto Padrón-Narvarta (University of Granada), Vincente López Sánchez-Vizcaíno (University of Jaén) and Ivan Savov (University of Leeds).

  • Serpentinization and subsequent hydrothermal metasomatism of abyssal peridotite from the Mid-Atlantic Ridge (Hole 1268a, ODP Leg 209, 15o20' N Fracture Zone). The highly serpentinized peridotites recovered from Hole 1268a have been subsequently affected by a high-temperature (>350oC) fluid which significantly reduced bulk-rock MgO/SiO2 ratios, with talc formation resulting from the silica metasomatism. Talc formation was also accompanied by a shift in B isotope ratios to lower δ11B than those measured in nearby Holes 1272 and 1274 (Vils et al., 2009) which experienced similar degrees of serpentinization. Sr isotope ratios from Hole 1268a also suggest that these former peridotites have interacted with a greater volume of seawater-like fluid than Holes 1272 and 1274. The proximity of the high temperature Logatchev hydrothermal field suggests that this is a likely source of silica-metasomatism in Hole 1268a and the shift to lower δ11B values as a result of probable interaction with Logatchev fluids has interesting implications for the sub-surface plumbing which links the Logatchev heat source with the surface of the ocean floor.

 This work is being carried out in collaboration with Ivan Savov (University of Leeds), Samuele Agostini (IGG, CNR, Pisa) and Rob Newton (University of Leeds).

Other ongoing projects include:

  • Mantle Nd isotope heterogeneity: analytical resolution at the grain scale?

 in collaboration with Ethan Baxter (Boston University) and Jessica Warren (Stanford University)

  • Silicon isotope fractionation during hydrothermal alteration of abyssal peridotite

 in collaboration with Paul Savage (University of Oxford)

  • Paradoxes, conundrums and gaps: ancient Pb and Os in refractory mantle domains.

 in collaboration with Steven Shirey (Carnegie Institution) and Jessica Warren (Stanford University)

Recent publications

Harvey, J., Dale, C.W., Gannoun, A., Burton, K.W. (2011) Osmium mass balance in peridotite and the effect of mantle-derived sulphides on basalt petrogenesis. Geochimica et Cosmochimica Acta 75, 5574-5596

Harvey, J., Gannoun, A., Burton, K.W., Rogers, N.W., Schiano, P., Alard, O. (2010) The effects of metasomatic sulphide on mantle Re-Os systematics: Unravelling melt depletion and secondary processes. Geochim. Cosmochim. Acta 74, 293-320

 Harvey, J., Baxter, E.F. (2009). High precision Nd isotopic analysis of very small aliquots (1 - 10ng) with example application in garnet Sm/Nd geochronology: An improved TIMS method. Chem. Geol.  258 251-257

Godard, M., Lagabrielle, Y., Alard, O., Harvey, J.  (2008). Geochemistry of the highly depleted peridotites drilled at ODP Sites 1272 and 1274 (Fifteen-Twenty Fracture Zone, Mid-Atlantic Ridge): Implications for mantle dynamics beneath a slow spreading ridge. Earth Planet. Sci. Lett. 267, 410-425

Kikawa, E., Kelemen, P.B., Miller, J.D., Abe, N., Bach, W., Carlson, R.L., Casey, J.F., Chambers, L.M., Cheadle, M., Cipriani, A., Dick, H.B.J., Faul, U., Garces, M., Garrido, C.J., Gee, J.S., Godard, M.M., Graham, D.W., Griffin, D.W., Harvey, J., Idelfonse, B., Iturrino, G.J., Josef, J.A., Meurer, W.P., Paulick, H., Rosner, M., Schroeder, T., Seyler, M., Takazawa, E. (2007) Proceedings of the Ocean Drilling Program; scientific results; drilling mantle peridotite along the Mid-Atlantic Ridge from 14 degrees to 16 degree N; covering Leg 209 of the cruises of the drilling vessel JOIDES Resolution; Rio de Janeiro, Brazil, to St George, Bermuda; Sites 1268-1275; 6 May-6 July 2003. Proc. Ocean Drilling Program 209

Harvey, J., Gannoun, A., Burton, K.W., Rogers, N.W., Alard, O., Parkinson, I.J. (2006). Ancient melt extraction from the oceanic upper mantle revealed by 187Re-187Os isotopes in abyssal peridotites. Earth Planet. Sci. Lett. 244, 606-621

Paulick, H., Bach, W., Godard, M., De Hoog, C.-J., M., Suhr, G., Harvey, J. (2006). Alteration geochemistry of abyssal peridotites (Mid-Atlantic Ridge, 15°20'N, ODP Leg 209): Implications for fluid/rock interaction in slow spreading environments. Chem. Geol. 234, 179-210

Bach, W., Garrido, C., Paulick, H., Harvey, J., Rosner, M., and Ocean Drilling Program Leg 209 Shipboard Scientific Party (2004). Seawater – peridotite interactions: First insights from ODP Leg 209, MAR 15oN. Geochem. Geophys. Geosyst.  5, (9)

Kikawa, E., Kelemen, P.B., Miller, J.D., Abe, N., Bach, W., Carlson, R.L., Casey, J.F., Chambers, L.M., Cheadle, M., Cipriani, A., Dick, H.B.J., Faul, U., Garces, M., Garrido, C.J., Gee, J.S., Godard, M.M., Graham, D.W., Griffin, D.W., Harvey, J., Idelfonse, B., Iturrino, G.J., Josef, J.A., Meurer, W.P., Paulick, H., Rosner, M., Schroeder, T., Seyler, M., Takazawa, E. (2004) Proceedings of the Ocean Drilling Program; Initial reports; drilling mantle peridotite along the Mid-Atlantic Ridge from 14 degrees to 16 degree N; covering Leg 209 of the cruises of the drilling vessel JOIDES Resolution; Rio de Janeiro, Brazil, to St George, Bermuda; Sites 1268-1275; 6 May-6 July 2003. Proc. Ocean Drilling Program 209

Academic CV (pdf file)