My research primarily focuses on the application of non-traditional stable isotope systems (lithium and uranium) to understand the geochemical cycling of elements in a range of low temperature surficial environments. I am interested in looking at modern day analogues in order to understand past climate, global anoxic events and weathering regimes.
My current research focuses on the behaviour of Li isotopes during estuarine mixing, and the use of lithium isotopes as a silicate weathering tracer in a large multi-catchment river draining permafrost into the Arctic Ocean.
During my PhD at Macquarie University, Australia, I investigated the behaviour of uranium isotopes (U-series, 238U/235U and 236U/238U) during low temperature uranium ore formation processes, with the aim to assess their potential use as a tracer of redox processes, and ultimately as an exploration tool.
Murphy M.J., Froehlich, M.B., Fifield, L.K., Turner, S.P., and Schaefer, B.F., 2015. In-situ production of natural 236U in groundwaters and ores in high-grade uranium deposits. Chemical Geology 410, 213-222.
Murphy, M.J., Strandmann, P.A.E.P.v., Porcelli, D., Ingri, J., 2014. Li Isotope Behaviour in the Low Salinity Zone During Estuarine Mixing. Procedia Earth and Planetary Science 10, 204-207.
Murphy, M.J., Stirling, C.H, Turner, S.P., Schaefer, B.F. and Kaltenbach, A., 2014. Redox-controlled fractionation of 238U/235U during low temperature uranium mineralisation. Earth and Planetary Science Letters. 388, 306-317.
Portner, R.A., Daczko, N.R., Murphy, M.J., and Pearson, N.J., 2011. Enriching mantle melts within a dying mid-ocean spreading ridge: Insights from Hf-isotope and trace element patterns in detrital oceanic zircon. Lithos, 126, 355-368.
Portner, R.A., Murphy, M.J., and Daczko, N.R., 2011. A detrital record of lower oceanic crust exhumation within a Miocene slow-spreading ridge: Macquarie Island, Southern Ocean. Geological Society of America Bulletin, 123, 255-273.