TAPP

-
Ndimande, N., Howarth, G. H., Giuliani, A., Janney, P. E., le Roux, P., Guillong, M., ... & Haggerty, S. E. (2025). Neoproterozoic kimberlite and lamproite magmatism of the Man Craton, Liberia, from a common sub-lithospheric source. Mineralogy and Petrology, 1-21.
-
Howarth, G. H., Casetta, F., & Abersteiner, A. (2025). A review of olivine as a tool for understanding kimberlite petrogenesis and diamond potential. Mineralogy and Petrology, 1-24.
-
van Blerk, J., Howarth, G. H., Harris, C., & Janney, P. E. (2025). Oxygen isotope constraints on proto-kimberlite melt modification through assimilation of low δ18O recycled crust in the deep lithosphere. Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2024.12.028
-
Howarth, G. H., Giuliani, A., Bussweiler, Y., Tau, M., Hashibi, S., Janney, P. E., & Nowicki, T. E. (2024). Kimberlite pre-conditioning of the lithospheric mantle and implications for diamond survival: a case study of olivine and mantle xenocrysts from the Koidu mine (Sierra Leone). Mineralium Deposita, 1-19.
-
Qashani, Z., Hashibi, S., Howarth, G. H., Janney, P. E., le Roux, P., & Robey, J. (2024). Petrogenesis and indicator mineral chemistry of the K-richterite-and leucite-bearing diamondiferous Kareevlei Kaapvaal lamproite. Lithos, 470, 107527.
-
Giuliani, A., Oesch, S., Guillong, M., & Howarth, G. H. (2024). Mica Rb-Sr dating by laser ablation ICP-MS/MS using an isochronous calibration material and application to West African kimberlites. Chemical Geology, 649, 121982.
-
Abersteiner, A., Tarasov, A., Golovin, A., Howarth, G. H., & Kamenetsky, V. S. (2024). Kaapvaal lamproite melts (aka orangeites): A new type of alkali-carbonate liquid? insights from olivine-hosted multiphase inclusions (Silvery Home, South Africa). Geoscience Frontiers, 15(5), 101864.
-
O'Neal, E. W., Ostwald, A. M., Udry, A., Gross, J., Righter, M., Lapen, T. J., Darling. J., Howarth, G.H.,... & McQuaig, D. R. (2024). Source and parental melts of poikilitic shergottites: Implications for martian magmatism. Geochimica et Cosmochimica Acta, 373, 122-135.
-
Howarth, G. H., Kahle, B., Janney, P. E., Kahle, R., Du Plessis, A., Richardson, S. H., & Gurney, J. J. (2023). Caught in the act: Diamond growth and destruction in the continental lithosphere. Geology, 51(6), 532-536.
-
Aucamp, T., Howarth, G. H., Peel, C. J., Costin, G., Day, J. M., le Roux, P., ... & Bartoschewitz, R. (2023). Petrogenesis of the Dar al Gani (DaG) 1.1 Ma ejection‐paired olivine‐phyric shergottites and implications for~ 470 Ma Martian volcanism. Meteoritics & Planetary Science, 58(11), 1654-1676.
-
Peel, C. J., Howarth, G. H., Day, J. M., le Roux, P., & Alard, O. (2023). Constraints on martian depleted shergottite volcanism from the petrogenesis of olivine-phyric shergottites NWA 2046 and NWA 4925. Journal of African Earth Sciences, 202, 104901.
-
Fitzpayne, A., Giuliani, A., Howarth, G. H., Peters, B. J., Fehr, M. A., & Maas, R. (2023). Major-, trace-element and Sr-Nd-Hf isotope geochemistry of diamondiferous dykes from Tonguma and Koidu, Sierra Leone: Highly micaceous kimberlites formed by assimilation of metasomatised lithospheric mantle rocks. Chemical Geology, 630, 121475.
-
Harris, C., Eriksson, S., le Roux, P., & Howarth, G. H. (2023). The relationship between δ18O values and incompatible element and radiogenic isotope enrichment in the Mashikiri nephelinites, of the Karoo LIP, southern Africa. Lithos, 454, 107278.
-
Howarth, G. H., Costin, G., Peel, C. J., & Qashani, Z. (2023). Petrology of an apatite-calcite segregationary kimberlite from the Andriesfontein pipe, Kaapvaal craton. Lithos, 458, 107341.
-
Howarth, G. H., Marsh, J. S., Duncan, A. R., Harris, C., Heinonen, J. S., Richardson, S. H., ... & Zartman, R. E. 2023. Petrogenesis of the Tuli Basin high-Ti picrites and basalts, Karoo CFB, southern Africa: Classification, stratigraphy, emplacement, and mantle source heterogeneity. Lithos, 107040.
-
Büttner, S. H., van Huyssteen, A., Marima, E., du Plessis, A., Tshibalanganda, M., Schmidt, C., & Howarth, G. H. 2023. The capturing and decompression of melt inclusions in olivine and ilmenite megacrysts from the Monastery kimberlite, South Africa. Gondwana Research, 115, 81-97.
-
Burgin, D. L., Scott, J. M., le Roux, P. J., Howarth, G., Palmer, M. C., Czertowicz, T. A., ... & Stirling, C. H. 2023. Rapid characterisation of Mars' mantle reservoirs by in situ laser ablation 87Sr/86Sr analysis of shocked feldspar (maskelynite). Geochimica et Cosmochimica Acta, 341, 46-61.
-
Sarkar, S., Giuliani, A., Phillips, D., Howarth, G. H., Ghosh, S., & Dalton, H. 2022. Sublithospheric melt input in cratonic lamproites. Geology, 50(11), 1296-1300.
-
Howarth, G. H., Giuliani, A., Soltys, A., & Bussweiler, Y. 2022. Compositional variations in primitive kimberlite melts and entrained mantle cargo from a global survey of trace element compositions in kimberlite olivine. Journal of Petrology, 63(8), egac062.
-
Viljoen, A., Howarth, G. H., Giuliani, A., Fitzpayne, A., & Costin, G. 2022. Correlations between olivine composition and groundmass mineralogy in Sierra Leone kimberlites provide constraints on craton-specific melt-lithosphere interactions. Lithos, 430, 106846.
-
Howarth, G. H., & Nembambula, T. 2021. Petrogenesis of Kaapvaal lamproites (aka orangeites) constrained by the composition of olivine and similarities with kimberlites and other diamondiferous lamproites. Lithos, 406, 106499.
-
Ramsey, S. R., Howarth, G. H., Udry, A., & Gross, J. 2021. Nickel–manganese variability in olivine and Al‐in‐olivine thermometry for olivine‐phyric shergottites. Meteoritics & Planetary Science, 56(8), 1597-1618.
-
Udry, A., Howarth, G. H., Herd, C., Day, J. M., Lapen, T. J., & Filiberto, J. 2020. What martian meteorites reveal about the interior and surface of Mars. Journal of Geophysical Research: Planets. https://doi.org/10.1002/essoar.10503123.1
-
Howarth, G. H., & Giuliani, A. 2020. Contrasting types of micaceous kimberlite-lamproite magmatism from the Man Craton (West Africa): New insights from petrography and mineral chemistry. Lithos, 105483.
-
Howarth, G. H., & Gross, J. 2019. Diffusion-controlled and concentric growth zoning revealed by phosphorous in olivine from rapidly ascending kimberlite magma, Benfontein, South Africa. Geochimica et Cosmochimica Acta, 266, 292-306.
-
Rahib, R. R., Udry, A., Howarth, G. H., Gross, J., Paquet, M., Combs, L. M., ... & Day, J. M. 2019. Mantle source to near-surface emplacement of enriched and intermediate poikilitic shergottites in Mars. Geochimica et Cosmochimica Acta, 266, 463-496.
-
Combs, L. M., Udry, A., Howarth, G. H., Righter, M., Lapen, T. J., Gross, J., ... & Day, J. M. 2019. Petrology of the enriched poikilitic shergottite Northwest Africa 10169: Insight into the martian interior. Geochimica et Cosmochimica Acta, 266, 435-462.
-
Howarth, G. H., Moore, A. E., Harris, C., van der Meer, Q. H., & le Roux, P. 2019. Crustal versus mantle origin of carbonate xenoliths from Kimberley region kimberlites using CO-Sr-Nd-Pb isotopes and trace element abundances. Geochimica et Cosmochimica Acta, 266, 258-273.
-
Altunkaynak, Ş., Ünal, A., Howarth, G. H., Aldanmaz, E., & Nývlt, D. 2019. The origin of low-Ca olivine from ultramafic xenoliths and host basaltic lavas in a back-arc setting, James Ross Island, Antarctic Peninsula. Lithos, 342, 276-287.
-
Howarth, G. H., & Büttner, S. H. 2019. New constraints on archetypal South African kimberlite petrogenesis from quenched glass-rich melt inclusions in olivine megacrysts. Gondwana Research, 68, 116-126.
-
Abersteiner, A., Kamenetsky, V. S., Goemann, K., Giuliani, A., Howarth, G. H., Castillo-Oliver, M., ... & Cherry, A. 2019. Composition and emplacement of the Benfontein kimberlite sill complex (Kimberley, South Africa): Textural, petrographic and melt inclusion constraints. Lithos, 324, 297-314.
-
Howarth, G. H. 2018. Olivine megacryst chemistry, Monastery kimberlite: Constraints on the mineralogy of the HIMU mantle reservoir in southern Africa. Lithos 314-315, 658-668.
-
Howarth, G. H., Udry, A., & Day, J. 2018. Petrogenesis of basaltic shergottite Northwest Africa 8657: Implications for fO2 correlations and element redistribution during shock melting in shergottites. Meteoritics & Planetary Science. DOI: 10.1111/maps.12999
-
Howarth, G. H., & Harris, C. 2017. Discriminating between pyroxenite and peridotite sources for continental flood basalts (CFB) in southern Africa using olivine chemistry. Earth and Planetary Science Letters, 475, 143-151.
-
Howarth, G. H., Day, J. M., Pernet-Fisher, J. F., Goodrich, C. A., Pearson, D. G., Luo, Y., Ryabov, V. V., & Taylor, L. A. 2017. Precious metal enrichment at low-redox in terrestrial native Fe-bearing basalts investigated using laser-ablation ICP-MS. Geochimica et Cosmochimica Acta, 203, 343-363.
-
Pernet-Fisher, J. F., Day, J. M., Howarth, G. H., Ryabov, V. V., & Taylor, L. A. 2017. Atmospheric outgassing and native-iron formation during carbonaceous sediment–basalt melt interactions. Earth and Planetary Science Letters, 460, 201-212.
-
Udry, A., Howarth, G. H., Lapen, T. J., & Righter, M. 2017. Petrogenesis of the NWA 7320 enriched martian gabbroic shergottite: Insight into the martian crust. Geochimica et Cosmochimica Acta, 204, 1-18.
-
Howarth, G.H. & Udry, A. 2017. Trace elements and the petrogenesis of the intermediate, olivine-phyric shergottite NWA 10170. Meteoritics and Planetary Science DOI: 10.1111/maps.12799.
-
Howarth, G. H. & Taylor, L. A. 2016. Multi-stage kimberlite evolution tracked in zoned olivine from the Benfontein sill, South Africa. Lithos, 262, 384-397.
-
Jean, M. M., Taylor, L. A., Howarth, G. H., Peslier, A. H., Fedele, L., Bodnar, R. J., Y Guan, LS Doucet, DA Ionov, AM Logvinova, AV Golovin, & Sobolev, N.V. 2016. Olivine inclusions in Siberian diamonds and mantle xenoliths: Contrasting water and trace-element contents. Lithos 265, 31-41.
-
Howarth, G. H., Liu, Y., Chen, Y., Pernet‐Fisher, J. F., & Taylor, L. A. 2016. Postcrystallization metasomatism in shergottites: Evidence from the paired meteorites LAR 06319 and LAR 12011. Meteoritics & Planetary Science. DOI: 10.1111/maps.12576
-
Taylor, L. A., Logvinova, A. M., Howarth, G. H., Liu, Y., Peslier, A. H., Rossman, G. R., Guan, Y., Chen, Y., & Sobolev, N. V. 2016. Low water contents in diamond mineral inclusions: Proto-genetic origin in a dry cratonic lithosphere. Earth and Planetary Science Letters, 433, 125-132.
-
Howarth, G. H., Pernet-Fisher, J. F., Bodnar, R. J., & Taylor, L. A. 2015b. Evidence for the exsolution of Cl-rich fluids in Martian magmas: Apatite petrogenesis in the enriched lherzolitic shergottite Northwest Africa 7755. Geochimica et Cosmochimica Acta, 166, 234-248.
-
Howarth, G. H., Sobolev, N. V., Pernet-Fisher, J. F., Ketcham, R. A., Maisano, J. A., Pokhilenko, L. N., Taylor, D., & Taylor, L. A. 2015a. 3-D X-ray tomography of diamondiferous mantle eclogite xenoliths, Siberia: A review. Journal of Asian Earth Sciences, 101, 39-67.
-
Logvinova, A. M., Taylor, L. A., Fedorova, E. N., Yelisseyev, A. P., Wirth, R., Howarth, G.H, Reutsky, V.N., & Sobolev, N. V. 2015. A unique diamondiferous peridotite xenolith from the Udachnaya kimberlite pipe, Yakutia: role of subduction in diamond formation. Russian Geology and Geophysics, 56(1), 306-320.
-
Pernet-Fisher, J. F., Howarth, G. H., Pearson, D. G., Woodland, S., Barry, P. H., Pokhilenko, N. P., Pokhilenko, L.N. , Agashev, A.M., & Taylor, L. A. 2015. Plume impingement on the Siberian SCLM: Evidence from Re–Os isotope systematics. Lithos, 218, 141-154.
-
Barry, P. H., Hilton, D. R., Day, J. M., Pernet-Fisher, J. F., Howarth, G. H., Magna, T., & Taylor, L. A. 2015. Helium isotopic evidence for modification of the cratonic lithosphere during the Permo-Triassic Siberian flood basalt event. Lithos, 216, 73-80.
-
Howarth, G.H., Pernet-Fisher, J.F., Balta, J.B., Barry, P.H., Bodnar, R.J., & Taylor, L.A. 2014c. Two-stage polybaric formation of the new enriched, pyroxene-oikocrystic, lherzolitic shergottite, NWA 7397. Meteoritics and Planetary Science, 49, 1812-1830.
-
Pernet-Fisher, J.F., Howarth, G.H., Liu, Y., Chen, Y., & Taylor, L.A. 2014. Estimating the lunar mantle water budget from phosphates: Complications associated with silicate-liquid-immiscibility. Geochimica et Cosmochimica Acta, 144, 326-341.
-
Howarth, G.H., Sobolev, N.V., Pernet-Fisher, J.F., Barry, P.H., Penumadu, D., Puplampu, S., Ketcham, R.A., Maisano, J.A., Taylor, D., & Taylor, L.A. 2014b. The secondary origin of diamonds: multi-modal radiation tomography of diamondiferous mantle eclogites. International Geology Reviews, 56(9), 1172-1180.
-
Pernet-Fisher, J.F., Howarth, G.H., Liu, Y., Barry, P.H., Carmody, L., Valley, J.W., Bodnar, R.J., Spetsius, Z.V., & Taylor, L.A. 2014. Komsomolskaya diamondiferous eclogites: Evidence for oceanic crustal protoliths. Contributions to Mineralogy and Petrology, 167, 981-998.
-
Howarth, G.H., Barry, P.H., Pernet-Fisher, J.F., Baziotis, I., Pokhilenko, N.P., Pokhilenko, L.N., Bodnar, R.J., Taylor, L.A., & Agashev, A.V. 2014a. Superplume metasomatism: Evidence from Siberian mantle xenoliths. Lithos, 184-187, 209-224.
-
Howarth, G.H. & Skinner, E.M.W. 2013. Coherent Kimberlite at the Lace and Voorspoed (Group II) Kimberlite Pipes, Kroonstad Cluster, South Africa: Implications for root zone processes in the development of kimberlite pipes. Journal of Volcanology and Geothermal Research, 268, 1-16.
-
Howarth, G.H. & Prevec, S.A. 2013b. Trace element, PGE, and Sr-Nd isotope geochemistry of the Panzhihua mafic layered intrusion, SW China: Constraints on ore-forming processes and evolution of parent magma at depth in a plumbing-system. Geochimica et Cosmochimica Acta, 120, 459-478.
-
Howarth, G.H., Prevec, S.A., & Zhou, M-F. 2013. Timing of Ti-magnetite crystallization and silicate disequilibrium in the Panzhihua mafic layered intrusion: Implications for ore-forming processes. Lithos, 170-171, 73-89.
-
Howarth, G.H. & Prevec, S.A. 2013a. Hydration vs. oxidation: Modelling implications for Fe-Ti oxide crystallization in mafic intrusions, with specific reference to the Panzhihua intrusion, SW China. Geoscience Frontiers (Special Edition on the Panzhihua Intrusion), 4, 555-569.
-
Ganino, C., Harris, C., Arndt, N.T., Prevec, S.A., & Howarth, G.H. 2013. Assimilation of carbonate country rock by the parent magma of the Panzhihua Fe-Ti-V deposit (SW China): Evidence from stable isotopes. Geoscience Frontiers (Special Edition on the Panzhihua Intrusion), 4, 547-554.
-
Zhou, M-F., Chen, W.T., Wang, C.Y., Prevec, S.A., Liu, P.P., & Howarth, G.H. 2013. Two stages of immiscible liquid separation in the formation of Panzhihua-type Fe-Ti-V oxide deposits, SW China. Geoscience Frontiers (Special edition on the Panzhihua Intrusion), 4, 481-502.
-
Howarth, G.H. & Skinner, E.M.W. 2012. The geology and emplacement of the volcaniclastic infill at the Voorspoed Group II kimberlite (orangeite) pipe, Kroonstad cluster, South Africa. Journal of Volcanology and Geothermal Research, 231-232, 24-38.
-
Howarth, G.H. & Skinner, E.M.W. 2011. Petrology of the hypabyssal kimberlite of the Kroonstad Group II kimberlite (orangeite) cluster, South Africa: Evolution of the magma within the cluster. Lithos, 125, 795-808.
-
Hanson, E.K., Moore, J.M., Bordy, E.M. Marsh, J.S., Howarth, G., & Robey, J.V.A. 2009. Cretaceous erosion in central South Africa: Evidence from upper-crustal xenoliths in kimberlite diatremes. South African Journal of Geology, 112, 125-140.