GEOMAR  Wartho, Jo-Anne

Staff

Jo-Anne Wartho

FB 4: Dynamik des Ozeanbodens
FE Magmatische und hydrothermale Systeme

Office:
Phone:
+49 431 600 2122
Email:
jwartho(at)geomar.de

Address:
Wischhofstraße 1-3
24148 Kiel

kein

Education and Career

  • Since 2017 Senior Research Scientist and 40Ar-39Ar Laboratory Manager, GEOMAR Helmholtz Centre for Ocean Research Kiel.
  • 2014-2017 Senior Research Scientist, GEOMAR Helmholtz Centre for Ocean Research Kiel.
  • 2006-2014 Associate Research Professional and 40Ar-39Ar Laboratory Manager, Arizona State University, USA.
  • 2005-2006 Curtin University Special Research Fellow and Manager of the Western Australian Argon Isotope Facility, Curtin University, Australia.
  • 2003-200 Senior Research Fellow and Manager of the Western Australian Argon Isotope Facility, Curtin University, Australia.
  • 2000-2003 Research Fellow and Manager of the Western Australian Argon Isotope Facility, Curtin University, Australia.
  • 1997-2000 Leverhulme Trust grant post-doctoral fellowship, Open University, UK. 
  • 1994-1997 National Environmental Research Council (NERC) post-doctoral grant fellowship, Open University, UK.
  • 1992-1994 North Atlantic Treaty Organisation (NATO) Fellowship, University of California, Los Angeles, USA.
  • 1992 Post-doctoral research fellowship, University of Leeds, UK. 
  • 1992 PhD, University of Leeds, UK. ‘Argon isotope systematics and mineralogy of metamorphic hornblendes from the Karakoram’.
  • 1988-1991 PhD student, University of Leeds, UK.
  • 1987-1988 Research Assistant, Birkbeck College, University College London, UK, with Badley, Ashton and Associates Ltd.
  • 1987 BSc (Honours) degree majoring in Geology, City of London Polytechnic, UK.

Scientific Interests

  • 40Ar-39Ar and (U-Th)/He geochronology on terrestrial (crust and mantle) and lunar rocks.
  • Developing the (U-Th)/He method for dating extraterrestrial impact craters.
  • Experimental noble gas diffusion and solubility studies in minerals and melts.

Research funding and awards

  • 2017-2018 Co-Proponent on a “Portal deutsche Forschungsschiffe” grant proposal: “BATHYCHEM - The effect of intraplate volcanism on the geochemical evolution of oceanic lithosphere: Details mapping and sampling of the Bathymetrists Seamounts and adjacent fracture zones” (Maria S. Merian: December 2017 – February 2018).
  • 2011-2015 Principal-Investigator on a US $307,000 National Science Foundation (NSF) grant: “The next step in unravelling the Earth’s impact history: (U-Th)/He dating of impact structures”.
  • 2011 Mineralogical Society of Great Britain and Ireland Senior Bursary Award (US $600).
  • 2008 Mineralogical Society of Great Britain and Ireland Senior Bursary Award (US $700).
  • 2007-2010 Co-Investigator on a Norwegian Research Foundation grant: “The crustal architecture and exhumation history of the Neoproterozoic/early Palaeozoic East African-Antarctic Orogen, in northern Mozambique”.
  • 2007-2011 Chief-Investigator on a US $34.6 million Australian Government National Collaborative Research Infrastructure Strategy grant: ‘Structure and Evolution of the Australian Continent’.
  • 2006-2007 Chief-Investigator on an Australian Antarctic Division grant: “Enigmatic Orogeny during the dispersal of Rodinia: Deciphering the Record of Tectonic Reworking in the Vestfold Hills, Antarctica”.
  • 2006-2010 Chief-Investigator on a US $1.53 million Western Australian State Government Centres of Excellence in Science and Innovation Program grant.
  • 2005-2009 Curtin University Special Research Fellowship award (US $141,000): “Determining the ages and rates of deformation in the Earth’s crust”.
  • 2004-2007 Chief-Investigator on an Australian Research Council Large Discovery grant (US $126,000): “Understanding the Sibao Orogenic Belt in South China:  A part of the Rodinian Supercontinent assembly adjacent to Australia”.
  • 2002 Chief-Investigator on a Curtin University Small Linkage Grant (US $8,800): “40Ar-39Ar laser dating of vacuum encapsulated clay samples – A new development in geochronology”.
  • 2002 Chief-Investigator on an Australian Commonwealth Scientific and Research Organisation (CSIRO) Linkage Grant (US $14,900): “40Ar-39Ar laser dating of vacuum encapsulated clay samples – A new development in geochronology”.
  • 1997-2000 Co-Investigator on a Leverhulme Trust grant (US $202,000): “Crystal/melt noble gas partitioning: Insights into early Earth degassing”.
  • 1998-2000 Chief-Investigator on a National Environmental Research Council (NERC) Small Grant (US $21,600): “Determining the fundamental parameters of argon in feldspars and feldspathoids”.
  • 1998 Mineralogical Society of Great Britain and Ireland Senior Bursary Award (US $700).
  • 1997-1998 Chief-Investigator on an Open University Research and Development award (US $52,600); to install forescatter imaging and Electron Backscattered Diffraction (EBSD) detectors and software onto the Open University scanning electron microscope.
  • 1992-1994 NATO Research Fellowship award to study at the University of California, Los Angeles.
  • 1992 – 1994 Chief-Investigator of a NSF grant (US $15,000); for experimental work with NATO Fellowship, at the University of California, Los Angeles.
  • 1991  Mineralogical Society of Great Britain and Ireland (US $700) Student Bursary Award.

Membership and committees

  • Since 2020 Member of the Advisory Board for the Journal of Petrology (Oxford University Press).
  • 2005-2006 Member of the Earth Composition and Evolution Working Group for an AuScope ‘Structure and Evolution of the Australian Continent’ research grant (US $34.6 million) from the Australian Government National Collaborative Research Infrastructure Strategy.
  • 2005-2006 Council Committee Member of the Western Australian Division of the Geological Society of Australia.
  • Since 1989 Fellow of the Mineralogical Society of Great Britain.
  • Since 2002 Member of the Geochemical Society.
  • 1986-2019 Fellow of the Geological Society of London.
  • 2011-2015 Member of the Meteoritical Society.
  • 1992-2012 Member of the American Geophysical Union.

Publications (peer-reviewed)

  • Samrock, L., Hansteen, T. H., Dullo, W. C. and Wartho, J. A. (2022) Internal igneous growth, doming and rapid erosion of a mature ocean island: the Miocene evolution of Maio (Cabo Verde). International Journal of Earth Sciences, 111, 1129-1148. DOI 10.1007/s00531-022-02160-x.
  • Ukstins, I., Wartho, J. A., Cabrol, N. A., Grin, E. A., van Soest, M. C., Biren, M. B., Hodges, K. V. and Chong, G. (2022) An (U-Th)/He age for the small Monturaqui impact structure, Chile. Quaternary Geochronology, 67, 101217. DOI 10.1016/j.quageo.2021.101217.
  • Homrighausen, S., Hoernle, K., Wartho, J. A., Hauff, F. and Werner, R. (2021) Do the 85°E Ridge and Conrad Rise form a hotspot track crossing the Indian Ocean? Lithos, 398-399, 106234. DOI 10.1016/j.lithos.2021.106234.
  • Di Chiara, A., Tauxe, L., Staudigel, H., Florindo, F., Protti, M., Yu, Y., Wartho, J. A., van den Bogaard, P. and Hoernle, K. (2021) Earth’s magnetic field strength and the Cretaceous Normal Superchron: New data from Costa Rica. Geochemistry, Geophysics, Geosystems, 22 (4), e2020GC009605. DOI 10.1029/2020GC009605.
  • Cavosie, A.J., Biren, M.B., Hodges, K.V., Wartho, J-A., Horton, J.W., Koeberl, C. (2020) Dendritic reidite from the Chesapeake Bay impact horizon, Ocean Drilling Program Site 1073 (offshore northeastern USA): A fingerprint of distal ejecta? Geology, 49, 201-205. DOI 10.1130/G47860.1.
  • Homrighausen, S., Hoernle, K., Zhou, H., Geldmacher, J., Wartho, J-A., Hauff, F., Werner, R., Jung, S. and Morgan, J.P. (2020) Paired EMI-HIMU hotspots in the South Atlantic-Starting plume heads trigger compositionally distinct secondary plumes? Science Advances, 6 (28). eaba0282. DOI 10.1126/sciadv.aba0282.
  • Long, X., Geldmacher, J., Hoernle, K., Hauff, F., Wartho, J. A., Garbe-Schönberg, D. (2020) Origin of isolated seamounts in the Canary Basin (East Atlantic): The role of plume material in the origin of seamounts not associated with hotspot tracks. Terra Nova, 32, 390-398. DOI 10.1111/ter.12468.
  • Samrock, L.K., Wartho, J-A., Hansteen, T.H. (2019) 40Ar-39Ar geochronology of the active phonolitic Cadamosto Seamount, Cape Verde. Lithos, 344-345, 464-481. DOI 10.1016/j.lithos.2019.07.003. 
  • Biren, M.B., Wartho, J-A., van Soest, M.C., Hodges, K.V., Cathey, H., Glass, B.P., Koeberl, C., Horton, J.W., Hale, W. (2019) (U-Th)/He zircon dating of Chesapeake Bay distal impact ejecta from ODP site 1073. Meteoritics and Planetary Science, 54, 1840-1852. DOI 10.1111/maps.13316.
  • Timm, C., de Ronde, C.E.J., Hoernle, K., Cousens, B., Wartho, J-A., Caratori Tontini, F., Wysoczanski, R., Hauff, F., and Handler, M. (2019) New age and geochemical data from the Southern Colville and Kermadec Ridges, SW Pacific: Insights into the recent geological history and Petrogenesis of the Proto-Kermadec (Vitiaz) Arc. Gondwana Research, 72, 169-193. DOI 10.1016/j.gr.2019.02.008. 
  • Dürkefälden, A., Hoernle, K., Hauff, F., Wartho, J-A., van den Bogaard, P., Werner, R. (2019) Age and geochemistry of the Beata Ridge: Primary formation during the main phase (~89 Ma) of the Caribbean Large Igneous Province. Lithos, 328-329, 69-87. DOI 10.1016/j.lithos.2018.12.021. 
  • Mercer, C.M., Hodges, K.V., Jolliff, B.L., van Soest, M.C., Wartho, J-A., Weirich, J.R. (2019) Exploring the variability of argon loss in Apollo 17 impact melt rock 77135 using high-spatial resolution 40Ar/39Ar geochronology. Meteoritics and Planetary Science, 54, 721-739. DOI 10.1111/maps.13240.
  • Long, X., Geldmacher, J., Hoernle, K., Hauff, F., Wartho, J-A., Garbe-Schönberg, D., Grevemeyer, I. (2019) Age and origin of Researcher Ridge and an explanation for the 14°N anomaly on the Mid-Atlantic Ridge by plume-ridge interaction. Lithos, 326-327, 540-555. DOI 10.1016/j.lithos.2019.01.005.
  • Homrighausen, S., Hoernle, K., Hauff, F., Wartho, J-A., van den Bogaard, P., Garbe-Schönberg, D. (2018) New age and geochemical data from the Walvis Ridge: The temporal and spatial diversity of South Atlantic intraplate volcanism and its possible origin. Geochemica et Cosmochimica Acta, 245, 16-34. DOI 10.1016/j.gca.2018.09.002
  • Homrighausen, S., Hoernle, K., Hauff, F., Geldmacher, J., Wartho, J-A., van den Bogaard, P., Garbe-Schönberg, D. (2018) Global distribution of the HIMU end member: Formation through Archean plume-lid tectonics. Earth-Science Reviews, 182, 85-101. DOI 10.1016/j.earscirev.2018.04.009.
  • Homrighausen, S., Hoernle, K., Geldmacher, J., Wartho, J-A., Hauff, F., Portnyagin, M., Werner, R., van den Bogaard, P., Garbe-Schönberg, D. (2018) Unexpected HIMU-type late-stage volcanism on the Walvis Ridge. Earth and Planetary Science Letters, 492, 251-263. DOI 10.1016/j.epsl.2018.03.049.
  • Kaulfuss, W., Lee, D.E., Wartho, J-A., Bowie, E., Lindqvist, J.K., Conran, J.G., Bannister, J.M., Mildenhall, D.C., Kennedy, E.M., Gorman A.R. (2018) Geology and palaeontology of the Hindon Maar Complex: A Miocene terrestrial fossil Langerstätte in southern New Zealand. Paleogeography, Palaeoclimatology, Palaeoecology, 500, 52-68. DOI 10.1016/j.palaeo.2018.03.022.
  • Fox, B.R.S., D’Andrea, W.J., Wilson, G.S., Lee, D.E., Wartho, J-A. (2017) Interaction of polar and tropical influences in the mid-latitudes of the Southern Hemisphere during the Mi-1 deglaciation. Global and Planetary Change, 155, 109-120. DOI 10.1016/j.gloplacha.2017.06.008.
  • Schultz, M.H., Hodges, K.V., Ehlers, T.A., van Soest, M., Wartho, J-A. (2017) Thermochronological constraints on the slip history of the South Tibetan detachment system in the Everest region, southern Tibet. Earth and Planetary Science Letters, 459, 105-117. DOI 10.1016/j.epsl.2016.11.022.
  • Biren, M.B., van Soest, M.C., Wartho, J-A., Hodges, K.V., Spray, J.G. (2016) Diachroneity of the Clearwater West and Clearwater East impact structures indicated by the (U-Th)/He dating method. Earth and Planetary Science Letters, 453, 56-66. DOI 10.1016/j.epsl.2016.07.053.
  • Borneman, N.L., Hodges, K.V., Wartho, J-A., van Soest, M.C., Bohon, W., Cronk, S.S., Ahmad, T. (2015) Age and structure of the Shyok Suture in the Ladakh region of northwestern India: Implications for slip on the Karakoram Fault System. Tectonics, 34, 10, 2011-2033. DOI 10.1002/2015TC003933. 
  • Adams, B., Hodges, K.V., Whipple, K.X., Ehlers, T.A., van Soest, M.C., Wartho, J-A., (2015) Constraints on the tectonic and landscape evolution of the Bhutan Himalaya from thermochronology. Tectonics, 34, 1329-1347. DOI 10.1002/2015TC003853. 
  • Tapia, C.A., Wilson, G.S., Ishman, S.E., Wilke, H.G., Wartho, J-A., Winter, D., Martínez-Pargo, R. (2015) An integrated sequence stratigraphic and chronostratigraphic analysis of the Pliocene, Tiburon Basin succession, Mijillones Peninsula, Chile. Global and Planetary Change, 131, 124-147. DOI 10.1016/j.gloplacha.2015.05.005.
  • Mercer, C.M., Young, K.E., Weirich, J.R., Hodges, K.V., Jolliff, B.L., Wartho, J-A., van Soest, M. (2015) Refining lunar impact chronology through high spatial resolution 40Ar/39Ar dating of impact melts. Science Advances, 1, e1400050. DOI 10.1126/sciadv.1400050.
  • Fox, B., Wartho, J-A., Wilson, G., Nelson, F.E., Kaulfuss, U. (2015) Long-term evolution of an Oligocene/Miocene maar lake from Otago, New Zealand. Geochemistry Geophysics Geosystems, 16, 59-76. DOI 10.1002/2014GC005534.
  • Biren, M.B., van Soest, M.C., Wartho, J-A., Spray, J.G. (2014) (U-Th)/He dating of uplift-induced cooling in a complex terrestrial impact structure: The Manicouagan example. Chemical Geology, 377, 56-71. DOI 10.1016/j.chemgeo.2014.03.013.
  • Wartho, J.A., Kelley, S.P., Elphick, S.C. (2013) Ar diffusion and solubility measurements in plagioclase using the Ultra-Violet Laser Ablation Microprobe. In: Advances in 40Ar/39Ar Dating: From Archaeology to Planetary Sciences, Jourdan, F. (Ed.), Geological Society Special Publications, 378, 137-154. DOI 10.1144/SP378.13. 
  • Long, S.P., McQuarrie, N., Tobgay, T., Coutand, I., Cooper, F.J., Reiners, P.W., Wartho, J., Hodges, K.V. (2012) Variable shortening rates in the eastern Himalayan thrust belt, Bhutan: Insights from multiple thermochronologic and geochronologic datasets tied to kinematic reconstructions. Tectonics, 31, (5), TC5004. DOI 10.1029/2012TC003155. 
  • Ueda, K., Jacobs, J., Thomas, R.J., Kosler, J., Horstwood, M.S.A., Wartho, J-A., Jourdan, F., Emmel, B., Matola, R. (2012) Post-collisional high-grade metamorphism, orogenic collapse and differential cooling of the East African Oregen of Northeast Mozambique. Journal of Geology, 120, 507-530. DOI 10.1086/666876.
  • Wartho, J-A., van Soest, M.C., King, D.T. Jr., Petruny, L.W. (2012) An (U-Th)/He geochronological age for the shallow-marine Wetumpka impact structure, Alabama, USA. Meteoritics and Planetary Science, 47, 1243-1255. DOI 10.1111/j.1945-5100.2012.01381.x.
  • van Soest, M.C., Hodges, K.V., Wartho, J-A., Monteleone, B.D. and Ramezani, J., 2011, (U-Th)/He dating of terrestrial impact structures; The Manicouagan example. Geochemistry, Geophysics, Geosystems, 12, QOAA16. DOI 10.1029/2010GC003465.
  • Li, Z-X., Li, X-H., Wartho, J-A., Clark, C., Li, W-X., Zhang, C. Bao, C. (2010) Magmatic and metamorphic events during the Caledonian Wuyi-Yunkai Orogeny, southeastern South China: New age constraints and P-T conditions. Geological Society of America Bulletin, 122, 772-793.  DOI 10.1130/B30021.1.
  • Daszinnies, M.C., Jacobs, J., Wartho, J-A., and Grantham, G.H., 2009, Post Pan-African thermo-tectonic evolution of the north Mozambican basement and its implication in the Gondwana rifting.  Inferences from 40Ar/39Ar hornblende, biotite and titanite fission-track dating. In: Thermochronological Methods: From Paleotemperature Constraints to Landscape Evolution Models, Lisker, F. (Ed.), Geological Society Special Publications, 324, 261-286. DOI 10.1144/SP324.18.
  • Spaggiari, C.V., Wartho, J-A., Wilde, S.A. Bodorkos, S. (2008) Proterozoic development of the northwestern margin of the Archean Yilgarn craton. Precambrian Research, 162, 354-384. DOI 10.1016/j.precamres.2007.10.004. 
  • Emmel, B., Jöns, N., Kröner, A., Jacobs, J., Wartho, J-A., Schenk, V., Razakamanana, T., Austegard, A. (2008) From closure of the Mozambique ocean to Gondwana breakup - new evidence from geochronological data of the Vohibory terrane, SW Madagascar. Journal of Geology, 116, 21-381. DOI 10.1086/524121.
  • Li, Z-X., Wartho, J-A., Occhipinti, S., Zhang, C-L., Li, X-H., Bao, C. (2007) Early history of the eastern Sibao Orogen (South China) during the assembly of Rodinia: New mica 40Ar/39Ar dating and SHRIMP U-Pb detrital zircon provenance constraints. Precambrian Research, 159, 79-94. DOI 10.1016/j.precamres.2007.05.003.
  • Downes, P., Wartho, J-A., Griffin, B.J. (2006) Magmatic evolution and ascent history of the Aries micaceous kimberlite, Central Kimberley Basin, Western Australia: Evidence from zoned phlogopite phenocrysts, and UV laser 40Ar/39Ar analysis of phlogopite-biotite. Journal of Petrology, 47, 1751-1783.  DOI 10.1093/petrology/egl026. 
  • Willner, A.P., Thomson, S.N., Kröner, A., Wartho, J-A., Wijbrans, J., Hervé, F. (2005) Time markers for the evolution and exhumation history of the Upper Paleozoic paired metamorphic belt in Central Chile (34°-35°30’S). Journal of Petrology, 46, 1835-1858. DOI 10.1093/petrology/egi036. 
  • Quinn, D., Meere, P.A. Wartho, J-A. (2005) A chronology of foreland deformation: Ultra-violet laser 40Ar/39Ar dating of syn/late-orogenic intrusions from the Variscides of southwest Ireland. Journal of Structural Geology, 27, 1413-1425. DOI 10.1016/j.jsg.2005.02.003. 
  • Pirajno, F., Wartho, J-A. (2005) Appendix 1: Ar-Ar geochronology of a pseudotachylite sample from the Yarrabubba impact structure, Western Australia. In: Pirajno, F. (2005) Hydrothermal processes associated with meteorite impact structures: evidence from three Australian examples and implications for economic resources. Australian Journal of Earth Sciences, 52, 587-605.
  • Wartho, J-A., Kelley, S.P., Elphick, S.C. (2005) Estimates of Ar diffusion and solubility in leucite and nepheline: Electron microprobe imaging of Ar distribution in a mineral. American Mineralogist, 90, 954-962. DOI 10.2138/am.2005.1320.
  • Haines, P.W., Turner, S.P., Kelley, S.P., Wartho, J-A., Sherlock, S. (2004) 40Ar/39Ar dating of detrital muscovite in provenance investigations: a case study from the Adelaide Rift Complex, South Australia. Earth and Planetary Science Letters, 227, 297-311. DOI 10.1016/j.epsl.2004.08.020. 
  • Willner, A.P., Wartho, J-A., Kramm, U., Puchkov, V.N. (2004) Laser 40Ar-39Ar ages of single detrital white mica grains related to the exhumation of Neoproterozoic and Late Devonian high pressure rocks in the Southern Urals (Russia). Geological Magazine, 141, 161-172. DOI 10.1017/S0016756803008628. 
  • Mueller, W., Friche, H., Halliday, A.N., McCulloch, M.T., Wartho, J-A. (2003) Origin and migration of the Alpine Iceman. Science, 302, 862-866. DOI 10.1126/science.1089837.
  • Brooker, R.A., Du, Z., Blundy, J.D., Kelley, S.P., Allan, N.L., Wood, B.J., Chamorro, E.M., Wartho, J-A., Purton, J.A. (2003) The ‘zero charge’ partitioning behaviour of noble gases during mantle melting.  Nature, 423, 738-741. DOI 10.1038/nature01708.
  • Wartho, J-A., Kelley, S.P. (2003) 40Ar/39Ar ages in mantle xenolith phlogopites:  Determining the ages of multiple lithospheric mantle events and diatreme ascent rates in southern Africa and Malaita, Solomon Islands. In: Geochronology: Linking the Isotopic Record with Petrology and Textures, Vance, D. (Ed.), Geological Society Special Publications, 220, 231-248. DOI 10.1144/GSL.SP.2003.220.01.14. 
  • Chamorro, E.M., Brooker, R.A., Wartho, J-A., Wood, B.J., Kelley, S.P., Blundy, J.D. (2002) Ar partitioning between clinopyroxene and silicate melt at high pressures.  Geochimica et Cosmochimica Acta, 66, 507-519. DOI 10.1016/S0016-7037(01)00784-0.
  • Kempton, P.D., Downes, H., Neymark, L., Wartho, J.A., Sharkov, E.V., Zartman, R. (2001) Garnet granulite xenoliths from the northern Baltic Shield – The lower crust of the Paleoproterozoic LIP?  Journal of Petrology, 42, 731-763. DOI 10.1093/petrology/42.4.731.
  • Wartho, J-A., Kelley, S.P., Blake, S. (2001) Magma flow regimes in sills deduced from Ar isotope systematics of micas in host rocks.  Journal of Geophysical Research, 106, B3, 4017-4036. DOI 10.1029/2000JB900327. 
  • Kelley, S.P., Wartho, J-A. (2000) Rapid kimberlite ascent and the significance of Ar-Ar ages in xenolith phlogopites. Science, 289, 609-611. DOI 10.1126/science.289.5479.609. 
  • Wartho, J-A., Kelley, S.P., Brooker, R.A., Carroll, M.A., Villa, I.M., Lee, M.R. (1999) Direct measurement of argon diffusion profiles in a gem-quality Madagascar K-feldspar using the Ultra-violet Laser Ablation Micro-Probe. Earth and Planetary Science Letters, 170, 141-153. DOI 10.1016/S0012-821X(99)00088-6. 
  • Brooker, R.A., Wartho, J-A., Carroll, M.R., Kelley, S.P., Draper, D.S. (1998) Preliminary UVLAMP determinations of Ar partitioning between silicate melts and olivine or clinopyroxene crystals: Preliminary results and comparison with previous studies. Chemical Geology, 147, 185-200. DOI 10.1016/S0009-2541(97)00181-2.
  • Wartho, J-A., Rex, D.C., Guise, P.G. (1996) Excess argon in amphiboles linked to greenschist facies alteration in the Kamila Amphibolite Belt, Kohistan island arc system, Northern Pakistan:  Insights from 40Ar/39Ar step-heating and acid leaching experiments. Geological Magazine, 133, 595-609. DOI 10.1017/S0016756800007871.
  • Wartho, J-A. (1995) Apparent diffusive loss 40Ar/39Ar age gradients in amphiboles. Earth and Planetary Science Letters, 134, 395-407. DOI 10.1016/0012-821X(95)00113-Q.
  • Wartho, J-A. (1995) Photo-emission electron microscopy (PEEM) heating investigations of a natural amphibole sample. Mineralogical Magazine, 59, 121-127. DOI 10.1180/minmag.1995.59.394.12. 
  • Rex, D.C., Guise, P.G., Wartho, J-A. (1993) Disturbed 40Ar/39Ar spectra from hornblendes: Thermal loss or contamination? Chemical Geology, 103, 271-281. DOI 10.1016/0009-2541(93)90306-4.
  • Wartho, J-A., Dodson, M.H., Rex, D.C., Guise, P.G. (1991) Mechanisms of Ar release from Himalayan metamorphic hornblende. American Mineralogist, 76, 1446-1448.