Alexander Dickson

Alexander Dickson

Visiting Fellow
Tel: +44 (0) 1865 272062

My research involves investigating the interactions between environmental change and ocean chemistry during geologically rapid climatic events of the Cenozoic and Mesozoic, and over longer multi-million year timescales in the Phanerozoic. This research includes several themes:

1.  Developing and applying isotopic (molybdenum, osmium, uranium, cadmium, zinc, neodymium, lithium, rhenium) proxies for redox, nutrient cycling, weathering and water mass circulation in modern marine environments.

2.  Applying isotopic proxies in conjunction with Earth-system modelling to reconstruct redox, nutrient cycling, weathering and water mass circulation in past oceans.

3.     Refining the stratigraphic expression of abrupt climatic events in the geological record.

4.     Using trace metal abundances in biogenic carbonates as proxies for seawater chemistry over past environmental change events.

5.     Investigating trace metal-organic matter interactions in field and laboratory experiments.

I work within the Shell-Oxford collaboration in the Department of Earth Sciences (, and am a co-investigator on a NERC standard grant (RESPIRE 

  1. Hooker, J.N., Cartwright, J., Stephenson, B., Silver, C., Dickson, A.J. and Hseih, Y-T. (2017), Closed system fluid evolution in fracturing black shales, Appalachian Basin. AAPG Bulletin, doi: 10.1306/10031616030.
  2. Ruebsam, W., Dickson, A.J., Hoyer, E-M. and Schwark, L. (2017), Redox evolution of the semi-enclosed Kupferschiefer Sea (Late Permian): clues from organic geochemistry, trace metals and molybdenum isotopes. Gondwana Research 44, 205–218.
  3. Dickson, A.J., Saker-Clark, M., Jenkyns, H.C., Bottini, C., Erba, E., Russo, F., Naafs, D., Pancost, R.D., Robinson, S.A., Gorbanenko, O., van den Boorn, S.H.J.M. and Idiz, E. (2017), A Southern Hemisphere record of global trace-metal drawdown and orbital modulation of organic-matter burial across the Cenomanian–Turonian boundary (Ocean Drilling Program Site 1138, Kerguelen Plateau). Sedimentology 64, 186–203.
  4. Jenkyns, H.C., Dickson, A.J., Ruhl, M. and van den Boorn, S.H.J.M. (2017), Mafic volcanism, the Plenus Cold Event, enhanced weathering, and geochemical change: deconstructing OAE 2 (Cenomanian–Turonian, Late Cretaceous). Sedimentology 64, 16–43.
  5. Sweere, T., van den Boorn, S., Dickson, A.J. and Reichart, G-J. (2016), A comprehensive database of trace metal concentrations in modern marine settings: definition of new tools to distinguish continental margin upwelling settings from restricted basins. Chemical Geology 441, 235–245.
  6. Percival, L.M.E., Cohen, A.S., Davies, M.K., Dickson, A.J., Hesselbo, S.P., Jenkyns, H.C., Leng, M.J., Mather, T.A., Storm, M.S. and Xu, W. (2016), Osmium isotope evidence for two pulses of increased continental weathering linked to Early Jurassic volcanism and climate change. Geology 44, 759–762.
  7. Dickson, A.J., Jenkyns, H.C., Porcelli, D., van den Boorn, S., Idiz, E. and Owens, J. (2016), Corrigendum to “Basin-scale controls on the molybdenum-isotope composition of seawater during Oceanic Anoxic Event 2 (Late Cretaceous)” [Geochim. Cosmochim. Acta 178 (2016) 291-306]. Geochimica et Cosmochimica Acta, doi:1016/j.gca.2016.06.025.
  8. Penman, D.E., Kirtland Turner, S., Sexton, P., Norris, R., Dickson, A.J., Boulilia, S., Ridgwell, A., Zeebe, R.E., Zachos, J.C., Cameron, A., Westerhold, T. and Röhl, U. (2016), A North Atlantic carbonate compensation depth overshoot in the aftermath of the Palaeocene Eocene Thermal Maximum. Nature Geoscience 9, doi:10.1038/NGEO2757.
  9. Dickson, A.J., Jenkyns, H.C., Porcelli, D., van den Boorn, S. and Idiz, E. (2016), Basin-scale controls on the molybdenum-isotope composition of seawater during Oceanic Anoxic Event 2 (Late Cretaceous). Geochimica et Cosmochimica Acta 178, 291–306.
  10. Dickson, A.J., Cohen, A.S., Coe, A.L., Davies, M., Shcherbinina, E. and Gavrilov, Y. (2015), Evidence for weathering and volcanism during the PETM from Arctic Ocean and Peri-Tethys osmium isotope records. Palaeogeography, Palaeoclimatology, Palaeoecology 438, 300-307.
  11. Maslin, M.A. and Dickson, A.J. (2015), O-isotopes. In Encyclopedia of Marine Geosciences, edited by Jan Harff, Martin Meschede, Sven Petersen and Jörn Thiede. Springer Sciences, Dorcrecht. Doi:10.1007/978-94-007-6644-0_81-1.
  12. Dickson, A.J., Cohen, A.S. and Coe, A.L. (2014), Continental margin molybdenum isotope signatures from the early Eocene. Earth and Planetary Science Letters 404, 389-395.
  13. Aze, T., Pearson, P., Dickson, A.J., Bown, P.R., Badger, M., Pancost, R.D., Gibbs, S.J., Huber, B.T., Leng, M.J., Coe, A.L., Cohen, A.S. and Foster, G. (2014), Extreme warming of tropical waters during the Paleocene – Eocene Thermal Maximum. Geology 10.1130/G35637.1.
  14. Dickson, A.J., Rees-Owen, R., März, C., Cohen, A.S., Coe, A.L., Gavrilov, Y., Pancost, R.D. and Shcherbinina, E. (2014), The spread of marine anoxia on the Northern Tethys margin during the Paleocene-Eocene Thermal Maximum. Paleoceanography, DOI: 10.1002/2014PA002629.
  15. Hesselbo, S.P., Bjerrum, C.J., Hinnov, L.A., MacNiocall, C., Riding, J.B., van de Schootbrugge, B. and the Mochras Revisited Science Team (2013), Mochras borehole revisited: a new global standard for Early Jurassic earth history. Scientific Drilling 16, 81-91.
  16. Dickson, A.J. and Cohen, A.S. (2012), A molybdenum isotope record of Eocene Thermal Maximum 2: implications for early Eocene seawater redox. Paleoceanography 27, PA3230, doi:10.1029/2012PA002346.
  17. Dickson, A.J., Cohen, A.S. and Coe, A.L. (2012), Seawater oxygenation during the Paleocene-Eocene Thermal Maximum. Geology 40, doi:10.1130/G32977.1.
  18. Dickson, A.J., Leng, M.J., Maslin, M.A. and Röhl, U. (2010), Oceanic, atmospheric and ice-sheet forcing of South East Atlantic Ocean productivity and South African monsoon intensity during MIS-12 to 10. Quaternary Science Reviews 29, 3936-3947.
  19. Dickson, A.J., Leng, M.J., Maslin, M.A., Green, J., Sloane, H.J., Bendle, J.A., McClymont, E.L., and Pancost, R.D. (2010), Meridional overturning and Agulhas Leakage influences of South East Atlantic upper ocean hydrography during Marine Isotope Stage 11. Paleoceanography, doi:10.1029/2009PA001830.
  20. Dickson, A.J., Beer, C.J., Dempsey, C., Bendle, J.A., Maslin, M.A., McClymont, E.L., and Pancost, R.D. (2009), Oceanic forcing of the Marine Isotope Stage 11 interglacial. Nature Geoscience 2, doi:10.1038/ngeo527.
  21. Dickson, A.J., Leng, M.J., and Maslin, M.A. (2008), Mid-depth South Atlantic ocean circulation and chemical stratification during MIS-10 to 12: implications for atmospheric CO2. Climate of the Past 4, 333-344.
  22. Dickson, A.J., Austin, W.E.N., Maslin, M.A., Hall, I.R., and Kucera, M. (2008), Centennial-scale evolution of Dansgaard-Oeschger events in the northeast Atlantic Ocean between 39.5-56.5 ka BP. Paleoceanography, PA3206, doi:10.1029/2008PA001595.
  23. Maslin, M.A., Austin, P., Dickson, A., Murlis, J., Owen, M., and Panizzo, V. (2007), Audit of UK greenhouse gas emissions to 2020: will current government policies achieve significant reductions? UCL Environment Institute: Environment Policy Report Number 2007:1.