Simulating experimentally the high temperature and pressure conditions of planetary interiors in order to understand fundamental petrological and geochemical processes, such as core-mantle differentiation, mantle melting and magma genesis. Recent projects are focused on the variables controlling trace-element partitioning, element speciation, and the oxidation state of planetary interiors.

Mallmann G., O’Neill H.St.C. (2013). Calibration of an empirical thermometer and oxybarometer based on the partitioning of Sc, Y and V between olivine and silicate melt. Journal of Petrology, doi: 10.1093/petrology/egt001. < Journal link >

Fonseca R.O.C., Laurenz V., Mallmann G., Luguet A., Hoehne N., Jochum K.P. (2012). New constraints on the genesis and long-term stability of Os-rich alloys in the Earth’s mantle. Geochimica et Cosmochimica Acta 87, 227-242. < Journal link >

Ávila J.N, Ireland T.R., Lugaro M., Gyngard F., Zinner E., Mallmann G., Holden P. (2012). U-Th-Pb isotopic compositions in stardust SiC grains from the Murchison meteorite. 43rd Lunar and Planetary Science Conference, League City, Texas. Abstract #2709. < Conference link >

Chemale Jr. F., Mallmann G., Bitencourt, M.F.A., Kawashita K. (2012). Time constraints on magmatism along the Major Gercino Shear Zone, southern Brazil: Implications for West Gondwana reconstruction. Gondwana Research 22, 184-199. < Journal link >

Fonseca R.O.C., Mallmann G., O’Neill H.St.C., Campbell I.H., Laurenz V. (2011). Solubility of Os and Ir in sulfide melt: Implications for Re/Os fractionation during mantle melting. Earth and Planetary Science Letters 311, 339-350. < Journal link >

Mallmann G., O’Neill H.St.C. (2009). The Crystal/Melt Partitioning of V during Mantle Melting as a Function of Oxygen Fugacity Compared with Some Other Elements (Al, P, Ca, Sc, Ti, Cr, Fe, Ga, Y, Zr and Nb). Journal of Petrology 50, 1765-1794. < Journal link >

Mallmann G., O’Neill H.St.C., Klemme S. (2009). Heterogeneous distribution of phosphorus in olivine from otherwise well-equilibrated spinel peridotite xenoliths and its implications for the mantle geochemistry of lithium. Contributions to Mineralogy and Petrology 158, 485-504. < Journal link >

Mallmann G., O’Neill H.St.C. (2007). The effect of oxygen fugacity on the partitioning of rhenium between crystals and silicate melt during mantle melting. Geochimica et Cosmochimica Acta 71, 2837-2857. < Journal link >

Fonseca R.O.C., Mallmann G., O’Neill H.St.C., Campbell I.H. (2007). How chalcophile is rhenium? An experimental study of the solubility of Re in sulphide mattes. Earth and Planetary Science Letters 260, 537-548. < Journal link >

Mallmann G., Chemale Jr. F., Ávila J.N., Kawashita K., Armstrong R.A. (2007). Isotope geochemistry and geochronology of the Nico Pérez Terrane, Rio de la Plata Craton, Uruguay. Gondwana Research 12, 489-508. < Journal link >

Ávila J.N., Chemale Jr. F., Mallmann G., Kawashita K., Armstrong R.A. (2006). Combined stratigraphic and isotopic studies of Triassic strata, Cuyo Basin, Argentine Precordillera. Geological Society of America Bulletin 118, 1088-1098. < Journal link >

Ávila J.N., Chemale Jr. F., Mallmann G., Borba, A.W., Luft, F.F. (2005).  Thermal  evolution  of  inverted  basins:  Constraints from  apatite  fission  track  thermochronology  in  the  Cuyo Basin, Argentine Precordillera. Radiation Measurements 39, 603-611. < Journal link >

Conceição R.V., Mallmann G., Koester E., Schilling M., Bertotto G.W., Rodriguez-Vargas A. (2005). Andean subduction-related mantle xenoliths: Isotopic evidence of Sr-Nd decoupling during metasomatism. Lithos 82, 273-287. < Journal link >

Schilling M., Conceição R.V., Mallmann G., Koester E., Kawashita K., Hervé F., Morata D., Motoki A. (2005). Spinel-facies mantle xenoliths from Cerro Redondo, Argentine Patagonia: Petrographic, geochemical, and isotopic evidence of interaction between xenoliths and host basalt. Lithos 82, 485-502. < Journal link >

Rodriguez-Vargas A., Koester E., Mallmann G., Conceição R.V., Kawashita K., Weber M.B.I. (2005). Mantle diversity beneath the Colombian Andes, Northern Volcanic Zone: Constraints from Sr and Nd isotopes. Lithos 82, 471-484. < Journal link >