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My research in sedimentology and stratigraphy focuses on carbonate sedimentology, climate change, and tectonics. I am particularly interested in coral reef systems, both modern and ancient, and their associated sedimentary systems; as tools to address fundamental questions in paleoclimate variability and tectonics processes, and in turn the influence of these factors on the geometry, composition and evolution of these sedimentary systems. My research is multidisciplinary nature, encompassing traditional elements of sedimentology and stratigraphy, combined with the novel use of GIS, geophysics, paleobiology, paleoecology, and geochemistry (stables isotopes, trace elements, radiometric dating).
You can read the detailed voyage summary at: http://www.marine.csiro.au/nationalfacility/voyagedocs/2007/summarySS20072007.pdf.
Using available field observations and sedimentary, radiometric age, and numerical modeling data, we propose a new model of submerged reef development around Hawaii during the last two glacial cycles (250 kyr). This model provides a quantitative predictive stratigraphy for the reefs that we argue, if drilled, will yield new information on sea level and climate changes, as well as coral reef response over the last 250 kyr. http://www.agu.org/pubs/crossref/2007/2006GC001415.shtml On this basis we have recently submitted a full proposal to the Integrate Ocean Drilling Program (IODP) to drill these unique reefs.
New mapping and sampling of carbonate material from submarine terraces at -150 m and -220 m indicate that Lanai has been relative stable over the last 30 ka (Webster et al. 2007).
The conclusion that Lanai has been relatively stable, perhaps over the last 250 kyr also has major implications for the origin of subaerial coral conglomerates found up to +190 m above sea level on Lanai and +80 m on Molokai. These very controversial deposits have been interpreted as either uplifted shoreline or mega-tsunami deposits. Our new analysis (Webster et al. 2006b; DOI: 10.1007/s00531-006-0107-5) of the submerged terrace deposits suggests that the subaerial coral conglomerates on Lanai are more likely the result tsunami deposition with a minimum wave run-up >170 m.
Link to new paper detailing this work.http://www.springerlink.com/content/2223821152252373/?p=68a27af731de4296892a7a5362a59d05&pi=6 Collaborators: David Clague (MBARI), Juan Carlos Brag (Granada).
We are studying two unique sequences of drowned carbonate platforms and corals
reefs off Papua New Guinea (PNG) and Hawaii. Combining high
MBARI news realease http://www.mbari.org/news/homepage/webster-reefs.html) Collaborators: David Clague (MBARI), Eli Silver, Don Potts (UCSC), Laura Wallace (IGNS), Juan Carlos Braga (University of Granada), Christina Gallup, Kristin Riker-Coleman (UMD).
We have
begun using the drowned reefs as “dipsticks” to better understand the
tectonic
The Hawaiian Islands owe their evolution to the NW movement of the Pacific plate as it moves across a hotspot. How the lithosphere has responded to migrating volcanic loads in space and time is still controversial. Using new ages from the –150 m around Hawaii we were able to confirm previously published but poorly constrained subsidence rates for the Big Island (2.6 m/kyr) (Webster et al. 2004b). In contrast, new mapping and sampling of carbonate material from terraces at similar depths indicate that Lanai has been relative stable over the last 30 ka (Webster et al. 2006a). Collaborators: David Clague (MBARI), Eli Silver,(UCSC), Laura Wallace (IGNS), Christina Gallup, Kristin Riker-Coleman (UMD),
The history of sea-level, sea-surface temperature (SST) and salinity (SSS) variations during the last deglaciation is critical to our understanding of the processes controlling abrupt global climate change. However, there are relatively few studies documenting these changes. Last year we employed high-resolution bathymetric data, ROV sampling & observation, paleoecology, and radiometric dating techniques to precisely constrain the drowning history of the coral reef currently at –150 m below sea-level around Hawaii We found evidence that the drowning of this reef was associated with a large and abrupt jump in sea level during the last deglaciation (meltwater pulse 1A) (Webster et al. 2004b). During the course of our study we also identified two shallower drowned reefs of Kawaihea that may record the timing and amplitude of younger meltwater pulse events. Collaborating with colleagues at University of Hawaii will we sample these reefs this spring, followed by submersible dives to sample similar features off Hilo, eastern Hawaii this Oct.. Currently, work is focused on reconstructing late Glacial and Holocene millennial-seasonal scale paleoclimate variability (SST and SSS) using stable isotopes and Sr/Ca ratios in the fossil corals from Hawaii, GBR, Cook Islands and Papua New Guinea. I also recently participated in the IODP (Leg 310) expedition to drill the deglacial coral reefs around Tahiti in Sep-Oct 2005 http://www.ecord.org/exp/tahiti/310.html and the onshore Party in Bremen in Feb 2006. This project aims to reconstruct sea level and climate variations and understand the influence of these factors on reef evolution. Collaborators; David Clague (MBARI), Eli Silver, Don Potts, Christina Ravelo (UCSC), Christina Gallup, Kristin Riker-Coleman (UMD), Nicky Allison (UE), Gilbert Camoin (CEREGE), Yasufumi Iryu (Tohoku).
The following projects (and others) are available right now. If you have other research questions you are interested in tackling don't hesitate to contact me. Right now is a great time to think about further study - particularly if it is working on exciting problems (ie. abrupt climate change) in very beautiful places (ie. Hawaii, Great Barrier Reef, Tahiti, Papua New Guinea). Information about scholarship opportunities (International students included) and enrollment procedures at JCU are at: http://www.jcu.edu.au/office/grs/research.html http://www.jcu.edu.au/office/grs/scholarships/index.html Honours/masters/Phd projects (email or call me directly for me details) Submarine canyons processes along the GBR margin. Supervisors: Jody Webster (JCU), Rapheal Wust (JCU), Rob Beaman (JCU), Jody.Webster@jcu.edu.au Submarine landslides along the GBR margin. Supervisors: Jody Webster (JCU), Rob Beaman (JCU).Jody.Webster@jcu.edu.au
Pleistocene
stratigraphy, sedimentology and development of the
Computer
modeling of Quaternary reef evolution in the
Sedimentary facies and benthic habitat mapping of coral reefs using remote sensing data in the GBR and Coral Sea (Jody Webster (JCU). Jody.Webster@jcu.edu.au, Rob Beaman (JCU). Late glacial/Holocene climate change in the subtropical and tropical central Pacific ocean; millennial-seasonal scale climate variability recorded in fossil corals. Supervisors: Jody Webster (JCU), Jody.Webster@jcu.edu.au Abrupt sea-level change during the last deglaciation: records from submerged terraces off Hawaii (JCU). Jody.Webster@jcu.edu.au
MB1110:03 Introductory Marine Science (2) EA1002:03 Environmental Earth Science (2) (coordinator) EA2110:03 Sedimentary Geology (1) (coordinator) EA2800:03 Marine Sedimentary Environments (2) EA3700:03 Rainforest to Reefs (July intensive) EA3610:03 Marine Geology and Paleobiology (2) Link to LearnJCU
Tager, D., Webster, J. M., Potts, D., Renema, W., Braga, J. C., Pandolfi, J. M., Community composition and dynamics of Pleistocene reefs during successive sea-level lowstands versus highstands (In Review – Ecology Reports) Webster J. M., Braga J. C., Clague, D. A., Coleman-Riker K., Gallup C., Hein, J. R., Potts D., Renema, W., Riding, R., Silver, E., Wallace L., Coral Reef Evolution on Rapidly Subsiding Margins (In Review – Special Issue of Global and Planetary Change). O’Leary, M. J., Webster, J. M., McCulloch, M. T, Hearty, P. J., Uranium-series dating of crustose coralline algae (Corallinaceae) (In revision – Quaternary Geochronology) Koelling, M., Webster J. M., Camoin, G., Iryu, Y., Bard, E., Seard, C. SEALEX - Internal reef chronology and virtual drill logs from a spreadsheet-based reef growth model (Accepted in revision – Special Issue of Global and Planetary Change). Webster, J. M., Beaman, R. J., Davies, P. J., William, S.,Byrne, M. (2008). From Corals to Canyons: Exploring the Great Barrier Reef Margin (In press - EOS). Webster, J. M., Davies, P. J., Beaman, R. J., William, S., and Byrne, M. (2008). RV Southern Survey - voyage summary; Marine National Facility 18 pp; http://www.marine.csiro.au/nationalfacility/voyagedocs/2007/summarySS20072007.pdf. Lewis, S., Wust, R., Webster, J. M., and Shields., G., 2008. A revised sea-level curve for the Great Barrier Reef and eastern Australia over the last 7,000 years, Terra Nova., 20 (1), 78-81. Beaman, R. J., Webster J. M., Wust, R. J. A., 2008. New evidence for drowned shelf edge reefs in the Great Barrier Reef, Australia, Marine Geology., 247, (1-2), 17-36. Allison, N., Adrian A. F., Webster J. M., Clague, D. A., 2007. Palaeoenvironmental records from fossil corals: the effects of submarine diagenesis on temperature and climate estimates, Geochimica, Cosmochimica Acta., 71, 4693–4703. Hughey, J. R., Braga, J. C., Aguirre, J., Woelkerling, W. J., Webster, J. M., Stamatoyannopoulos, G. (In Press 26 June for publication in April 2008 issue (Vol. 44, no. 2). Analysis of Ancient DNA from fossil corallines (CORALLINELES, 1 Rhodophyta) (Journal of Phycology). Webster, J. M., L. M. Wallace, D. A. Clague, and J. C. Braga, 2007. Numerical modeling of the growth and drowning of Hawaiian coral reefs during the last two glacial cycles (0–250 kyr), Geochem. Geophys. Geosyst., 8, Q03011, doi:10.1029/2006GC001415.http://www.agu.org/pubs/crossref/2007/2006GC001415.shtml Webster J. M., Clague, D. A., Braga J. C. 2007. Support for the Giant Wave (Mega-Tsunami) Hypothesis: evidence from the submerged terraces off Lanai, Hawaii (International Journal of Earth Sciences, 96, (3), 517-524. http://www.springerlink.com/content/2223821152252373/?p=68a27af731de4296892a7a5362a59d05&pi=6 Camoin, G. F., Iryu, Y., McInroy, D.B., and the Expedition 310 Scientists 2007. Proceedings of the Integrated Ocean Drilling Program 310, doi:10.2204/iodp.proc.2310.2101.2007. (for the proceedings go to the following link) http://publications.iodp.org/proceedings/310/310toc.htm 2006, Evidence of Holocene uplift in east New Britain, Papua New Guinea, Geophys. Res. Lett., 33, L18612, doi:10.1029/2006GL026596. http://www.agu.org/pubs/crossref/2006/2006GL026596.shtml Webster J. M., Clague, D. A., Braga J. C., Spalding, H., Renema W., Kelley, C., Applegate., B., Smith, J., Paull. C. K., Moore. G. J., Potts D., 2006a. Drowned coralline algal dominated deposits off Lanai, Hawaii; carbonate accretion and vertical tectonics over the last 30 ka. Marine Geology, 225, 223-246. http://hera.ugr.es/doi/16521602.pdf Webster J. M., Wallace L., Silver E., Applegate., B., Potts D., Braga J. C., Coleman-Riker K and Gallup C, 2004. Drowned carbonate platforms in the Huon Gulf, Papua New Guinea. Geochemistry, Geophysics, Geosystems 5, Q11008, doi:10.1029/2004GC000726.http://www.agu.org/journals/gc/gc0411/2004GC000726/ Webster J. M., Clague, D. A., Coleman-Riker K., Gallup C., Braga J. C., Potts D., Moore. G. J., Winterer, E. L., Paull. C. K, 2004. Drowning of the -150 m reef off Hawaii: A casualty of global meltwater pulse 1A?. (Geology, 32, 49-252. doi:10.1130/G20170.1). Davies,
P.J, Braga J. C, Lund, M., Webster
J. M.
2004. Holocene deep water algal buildups on the Eastern Australian Shelf. PALAIOS, 19, 598-609. Webster J. M., Wallace L., Silver E., Potts D., Braga J. C., Renema W., Coleman-Riker K and Gallup C, 2004. Coralgal composition of drowned carbonate platforms in the Huon Gulf, Papua New Guinea; implications for lowstand reef development and drowning. Marine Geology, 204, 59-89 doi:10.1016/S0025-3227(03)00356-6). Webster, J. M., Davies, P.J, 2003. Coral variations in two deep drill cores from the Northern Great Barrier Reef: significance for the Pleistocene development of the Great Barrier Reef. In: Blanchon, P and Montaggioni, L. P, (Eds), Late Quaternary Reef Development, Elsevier, Sedimentary Geology, 159, 1-2, 61-80. Abram N., Webster J. M., Davies P. J, Dullo W. Ch, 2001. Biological response of coral reefs to sea-surface temperature variation: Evidence from the raised Holocene reefs at Kikai-jima (Ryukyu Islands, Japan). Coral Reefs, 20, 221-234.http://www.springerlink.com/link.asp?id=3y2fd27jh7grk3am International Consortium for Great Barrier Reef Drilling, 2001. (Alexander, I., Andres, M. S., Braithwaite, C. J. R., Braga, J. C., Davies P. J., Elderfield. H., Gilmour, M. A., Kay, R. L., Kroon, D., McKenzie, J. A., Montaggioni L. F., Skinner, A., Thompson, R., Vasconcelos, C., Webster J. M. and Wilson, P. A.). New constraints on the origin of the Australian Great Barrier Reef: Results from an international project of deep coring. Geology.http://www.gsajournals.org/gsaonline/?request=get-abstract&issn=0091 7613&volume=029&issue=06&page=0483 Webster
J. M.,
P.J. Davies and Konishi K, 1998. Model of fringing reef development in
response to progressive sea-level fall over 7,000 – (Ryukyu Islands,
Japan). Coral Reefs 17 (1998) 3, 289-308, Special Issue of Coral Reefs
(Holocene and Pleistocene reef geology).
http://link.springer.de/link/service/journals/00338/bibs/8017003/80170289.htm
Short web article for MARGO "Tales from the Sea" summarizing the Expedition. http://ems.anu.edu.au/margo/html/tales.htm. Also check out these pictures of Tahiti and the drilling http://ems.anu.edu.au/margo/html/pictures.htm#Leg310
Check out this recent news paper interview (Honolulu Advertiser) talking about Hawaiian Holocene climate variability. http://the.honoluluadvertiser.com/article/2005/Feb/14/ln/ln40p.html. A manuscript dealing with data is in preparation.
Check out the recent news release http://www.mbari.org/news/homepage/2004/reefs-webster.html and and paper in Geology, 32, 49-252. doi:10.1130/G20170.1. Here we present new evidence indicating the drowning of the Hawaiian reef (now at -150 m below present sea-level) was caused by global meltwater pulse 1A, a catastrophic jump in sea-level associated with ice sheet collapse ~ 14-15 ka.
Recent
As pointed out in the
journal Science [DOI:
10.1126/science.306.5705.2167a]
this &nb |
resolution, sedimentologic and radiometric data we have been able to characterize
platform drowning and backstepping in response to rapid subsidence and
eustatic sea-level changes (Webster et al. 2004a). Based on our analysis we
have: (1) identified a clear sedimentary signature of rapid drowning
(Webster et al. 2004a, Webster et al. in prep) and, (2) presented a
quantitative model of platform evolution and, (3) showed for the first time
that they drowned during smaller amplitude interstadial sea-level rise
events as well as major deglaciations (Webster et al. 2004c). 
behavior of the earth’s crust in convergent and mid plate hotspot
settings. In PNG, we found that the platforms tilt not only NE towards the
Australian-South Bismarck plate boundary but also towards to NW in the
direction of the major thrust mass (Finisterre Range), providing new
insights and constraints on foreland basin evolution (Webster et al. 2004c).
New U/Th coral ages from raised reefs on New Britain also provide the first
constraints on uplift rates associated with collision between the South
Bismarck-Solomon Sea Plate (Riker-Coleman