PhD University of Michigan Oceanography (1996)
Awards & Honors
Geological Society of America (GSA) Fellow (2013)
paleooceanography, marine geology, stratigraphy
(1) Oceanic gas hydrates: Clathrate hydrates of gas (gas hydrates) are crystalline substances composed of water and certain gases (usually methane) that occur naturally in pore space of marine sediment. These hydrates are of interest because they represent a potential future energy resource and modulator of climate change. My research has included studies on the distribution and composition of gas hydrate in sediment columns, experimental work on the thermodynamic conditions of gas hydrate formation and dissociation, and numerical models pertaining to the release of methane into the ocean and atmosphere.
(2) Geochemical cycling during major oceanographic change: This pursuit involves the construction of chemical profiles in marine sediment across critical time intervals in the evolution of our ocean. Previous work has included trace element profiles across the Cenomanian/Turonian and Miocene/Pliocene boundaries. Currently I am working toward understanding events in the early Paleogene (Paleocene-middle Eocene) and early Aptian, times characterized by major warmth and massive input of carbon.
(3) Sediment-hosted metalliferous ore deposits: marine sedimentary rocks are the host to large ore deposits of certain metals, including iron, manganese, vanadium and barium (e.g., ores of Fe, V, Ba). In most cases, these deposits result from the combination of unusual paleoceanographic conditions and subsequent weathering or alteration processes. My current research in this area focuses on the origin of BIF hosted iron ores and black-shale hosted vanadium ores in Australia.
(4) Mixed siliciclastic/carbonate margins: Many continental margins, both modern and ancient, receive significant amounts of terrigenous clastic and shallow marine carbonate sediment. These mixed siliciclastic/carbonate depositional systems have not been well-studied in the past. The North Queensland margin of Australia is the largest extant mixed clastic/carbonate system. Currently I am quantifying sediment deposition on this margin with the aim of establishing a flux-based model of accumulation.
First-authored papers by students and research scientists (Last 10 years)
*Slotnick, B.S., G.R. Dickens, C.J. Hollis, J.S. Crampton, C.P. Strong & and A. Phillips, in press. The onset of the Early Eocene Climatic Optimum at Branch Stream, Clarence River valley, New Zealand, New Zealand Journal of Geology and Geophysics.
*Slotnick, B.S., V. Lauretano, J. Backman, G. R. Dickens, A. Sluijs & L. Lourens, 2015. Early Paleogene variations in the calcite compensation depth: new constraints using old borehole sediments from across Ninetyeast Ridge, central Indian Ocean, Climate of the Past, 11: 473-493, doi:10.5194/cp-11-473-2015.
*Chatterjee, S., G. Bhatnagar, B. Dugan, G.R. Dickens, W.G. Chapman & G.J. Hirasaki, 2014. The impact of lithologic heterogeneity and focused fluid flow upon gas hydrate distribution in marine sediments. Journal of Geophysical Research: Solid Earth, 119: doi:10.1002/2014JB011236.
*Komar, N., R.E.. Zeebe & G.R. Dickens, 2013. Understanding long-term carbon cycle trends: The late Paleocene through the early Eocene. Paleoceanography, 28: 650-662. DOI: 10.1002/palo.20060
*Reghellin, D., G.R. Dickens & J. Backman, 2013. The relationship between wet bulk density and carbonate content in sediments from the Eastern Equatorial Pacific. Marine Geology: 344, 41-52.
*Slotnick, B.S., G.R. Dickens, *M.J. Nicolo, C.J. Hollis, J.S. Crampton, J.C. Zachos & A. Sluijs, 2012. Large amplitude variations in carbon cycling and terrestrial weathering during the latest Paleocene and earliest Eocene at Mead Stream, New Zealand. Journal of Geology, 120: 487-505.
*Gu, G., G.R. Dickens, G. Bhatnagar, F.S. Colwell, G.J. Hirasaki & W.G. Chapman, 2011. Abundant early Palaeogene marine gas hydrates despite warm deep-ocean temperatures. Nature Geoscience, 4: 848-851.
*Chatterjee, S., G.R. Dickens, G. Bhatnagar, W.G. Chapman, B. Dugan, *G.T. Snyder & G.J. Hirasaki, 2011. Pore water sulfate, alkalinity, and carbon isotope profiles in shallow sediment above marine gas hydrate systems: A numerical modeling perspective. Journal of Geophysical Research, 116: B09103, doi:10.1029/2011JB008290.
*Bhatnagar G., *S. Chatterjee, W.G., Chapman, B. Dugan, G.R. Dickens & G.J. Hirasaki, 2011. Analytical theory relating the depth of the sulfate-methane transition to gas hydrate distribution and saturation. Geochemistry, Geophysics, Geosystems, 12: Q03003, DOI: 10.1029/2010GC003397.
*Leon-Rodriguez, L. & G.R. Dickens, 2010. Constraints on ocean acidification associated with rapid and massive carbon injections: The early Paleogene record at ocean drilling program site 1215, equatorial Pacific Ocean. Palaeogeography, Palaeoclimatology, Palaeoecology, 298: 409-420, DOI: 10.1016/j.palaeo.2010.10.029
*Nicolo M.J., G.R. Dickens & C.J. Hollis, 2010. South Pacific intermediate water oxygen depletion at the onset of the Paleocene-Eocene thermal maximum as depicted in New Zealand margin sections. Paleoceanography, 25: PA4210, DOI: 10.1029/2009PA001904.
*Lewis S.E., R.A. Henderson, G.R. Dickens, G.A. Shields & S. Coxhell, 2010. The geochemistry of primary and weathered oil shale and coquina across the Julia Creek vanadium deposit (Queensland, Australia). Mineralium Deposita, 45: 599-620, DOI: 10.1007/s00126-010-0287-6.
*Bhatnager, G., W.G. Chapman, G.R. Dickens, B. Dugan & G.J. Hirasaki, 2008. Sulfate-methane transition as a proxy for average methane hydrate saturation in marine sediments. Geophysical Research Letters, 35: L03611, doi: 10.1029/2007GL032500.
*Francis, J.M., J.J. Daniell, A.W. Droxler, G.R. Dickens, S.J. Bentley, L.C. Peterson, B. Opdyke & L. Beaufort, 2008. Deep-water geomorphology of the mixed siliciclastic-carbonate system, Gulf of Papua, Journal of Geophysical Research-Earth Surface, 113: F01S16, doi: 10.1029/2007JF000851.
*Carson, B.E., *J.M. Francis, R.M. Leckie, A.W. Droxler, G.R. Dickens, S.J. Jorry, S.J. Bentley, L.C. Peterson & B.N. Opdyke, 2008. Benthic foraminiferal response to sea level change in the mixed siliciclastic-carbonate system of southern Ashmore Trough (Gulf of Papua). Journal of Geophysical Research-Earth Surface, 113: F01S20, doi: 0.1029/2006JF000629.
*Snyder, G.T., G.R. Dickens & *D.G. Castellini, 2007. Labile barite contents and dissolved barium concentrations on Blake Ridge: New perspectives on barium cycling above gas hydrate systems. Journal of Geochemical Exploration, 95: 48-65.
*Bhatnager, G., W.G. Chapman, G.R. Dickens, B. Dugan & G.J. Hirasaki, 2007. Generalization of gas hydrate distribution and saturation in marine sediments by scaling of thermodynamic and transport processes. American Journal of Science, 307: 861-900.
*Nicolo, M.J., G.R. Dickens, C.J. Hollis & J.C. Zachos, 2007. Multiple early Eocene hyperthermals: Their sedimentary expression on the New Zealand continental margin a