Phil Bart
Professor
PhD: Sedimentology; sequence and seismic stratigraphy. Marine geology; pattern and nature of glacioeustasy Rice University, 1997
Phone: (225) 578-3109
Fax: (225) 578-2302
E-mail: [email protected]
Personal Website: http://www.geol.lsu.edu/bart/bart/Welcome.html
Google Scholar Page: http://ow.ly/K1tY309WqWL
Office: 102B Howe-Russell Building
Area of Interest
High-latitude glacial stratigraphy and evolution of the Antarctic cryosphere
My research has focused on understanding the evolution of the Antarctic cryosphere
during the Neogene (i.e., the past 25 million years). Ice-cover on Antarctica is contained
in three distinct ice sheets (West Antarctic Ice Sheet, East Antarctic Sheet, and
Antarctic Peninsula Ice Sheet) rather than constituting a single glacial system. During
the Neogene, the Antarctic Ice Sheets have undergone dramatic modifications that either
forced and/or responded to climatic changes. Also within this timeframe, the Antarctic
cryosphere attained continental scale. At present, the continent contains sufficient
ice volume to raise global sea level by ~70 meters if the ice were melted and returned
to the global ocean. To date, I have studied the geologic record of major expansions
and contractions of all three glacial systems from the perspective of Antarctica's
outer-continental shelf stratigraphy. My students and I are currently funded by the
NSF Office of Polar Programs to collect marine seismic data on the eastern Ross Sea
(which receives ice volume drainage from the East Antarctic Ice Sheet, western Ross
Sea (which receives drainage from the West Antarctic Ice Sheet) and the pacific-margin
of the Antarctic Peninsula (which receives drainage from the Antarctic Peninsula Ice
Sheet). The objectives of our ongoing studies are to determine whether or not these
three very different glacial systems expanded and contracted in phase. These studies
are very important as we seek to predict how the ice sheets will behave in the future.
One major result obtained thus far is that all three systems experienced major expansions
into the marine realm during the early Pliocene when global climates were warmer than
present. This supports some numerical models that predict that future global warming
could have the unexpected effect of causing the ice sheets to expand.
Low-latitude clastic stratigraphy during the Last Glacial Cycle
My graduate students and I have collected seismic data during two research cruises
to the northeastern Gulf of Mexico (25 days total ship time). This data acquisition
was funded by a consortium of oil companies as part of a proposal effort in which
I participated at Rice University as a graduate student. I led the LSU group (M.S.
students Mr. Van Richmond, Ms. Heather McKowen, and Mr. Herberto Lafayette) which
focused on the northeastern Gulf of Mexico continental shelf. These research activities
on the Florida ramp margin were distinct from those conducted by Rice University group
on offshore Texas shelf-slope margin. In a separate effort, I have also acquired 3-D
and 2-D multichannel seismic data from offshore Nigeria (west Delta) from Conoco Inc.
via contacts I made when I worked at Conoco as a summer-intern prior to joining LSU.
A LSU graduate student (Toby Stewart) is utilizing the Nigeria data-set for his M.S.
degree. Using these seismic data sets, my graduate students and I evaluate the outer-shelf
stratigraphy of low-latitude margins utilizing seismic and core data (offshore Alabama,
west Florida, and Nigeria) particularly with regard to the last glacial cycle (LGC).
Earth is currently within an eustatic highstand/interglacial. The LGC is from 125,000
years before present (the previous highstand) to today. During the peak of the last
glacial maximum (LGM) at ~20,000 years ago, sea level was much lower than present.
The stratigraphy deposited during this time is being evaluated because it reveals
many clues concerning the nature of sea-level changes (and thus global ice-volume/climate
change) during the recent past. There are several reasons why the northeastern Gulf
of Mexico is an ideal place to evaluate the sea-level elevation at the peak of the
LGM. These include the fact that at the outer-continental shelf (where the LGM coast
lines are found) is not underlain by salt-domes, there is no major growth faulting
associated with large depocenters, and the ramp's basinward margin is underlain by
relatively unattenuated continental crust. Therefore, post-LGM subsidence in the area
is minimal and tectonically uncomplicated. Thus far, our work strongly suggests that
the LGM sea-level elevations were at ~70 meters below present, i.e., significantly
higher than is inferred using various other techniques (i.e., 160 to 100 meters below
present). This work is important as the scientific community attempts to explain why
Earth climates change abruptly (i.e., a few thousand years) from full glacial conditions
to full interglacial conditions. If our results are correct, the mechanisms invoked
to cause this abrupt climatic change need not be as dramatic as has traditionally
been assumed.
Antarctic marine geology and geophysics
Seismic/sequence stratigraphy
Sequence stratigraphy
Glacial sedimentology
Global-scale climate change
Last-glacial-cycle stratigraphy
Selected Publications
Warny, S. Anderson, J.B., Londeix, L., and Bart, P.J., 2007. Analysis of the dinoflagellate
cyst
genus Impletosphaeridium as a marker of sea-ice conditions off Seymour Island. Short
Research Paper. In: Antarctica: A Keystone in a Changing World – Online Proceedings
of the 10th ISAES, edited by A.K. Cooper and C.R. Raymond et al., USGS Open-File Report
2007-1047, 4 pages, URL: http://pubs.usgs.gov/of/2007/1047/srp/srp079/
Holloman, J. and Bart, P.J., Trough-mouth-fan evolution on the Pacific-margin of the Antarctic Peninsula outer continental shelf and its relation to sediment drifts on the adjacent continental rise. AGU Fall meeting, San Francisco, Ca
Bart, P.J., and Chow, J.M., Timing of West Antarctic Ice Sheet grounding events in Ross Sea during the middle Miocene: implications on the phase relationships with the East Antarctic Ice Sheet. AGU Fall meeting, San Francisco, Ca
Egan, D. and Bart, P.J., New data suggest early onset and dynamic history of outer continental shelf glacial grounding events on the Pacific-margin of the Antarctic Peninsula. GSA Annual meeting, Denver, CO
Chow, J. M., and Bart, P.J., Ice Sheet Advances on the Ross Sea continental shelf: A case for West Antarctic Ice Sheet vigor in the middle Miocene. Geological Society of America Annual meeting, Denver, CO
Bart, P.J., and Warny, S.A., An evaluation of the Messinian Salinity Crisis: Implications of new palynological results on the interpretation of late Miocene Antarctic Ice Sheet evolution. Antarctic Offshore Stratigraphy (ANTOSTRAT) Symposium, Erice, Italy
Chow, J.M, and Bart, P.J., Early and Middle Miocene advances of the Antarctic Ice sheet across the Ross Sea continental shelf. ANTOSTRAT Symposium, Erice, Italy
Bart, P.J., and Chow, J.M., Middle Miocene prograding wedges on the Ross Sea outer continental shelf. AGU Boston, Ma (invited)
Bart, P.J., Did the Antarctic Ice Sheets expand during the early Pliocene? Geological Society of America Annual meeting, Reno, Nevada
Bart, P.J., and Anderson, J.B., Extreme expansions of the Antarctic Ice Sheets during the late Neogene from the perspective of the Ross Sea outer continental shelf. AGU Fall meeting, San Francisco, Ca
Bart, P.J., Lafayette, H.C., McKowen, H.A., Richmond, R.V., Late Quaternary shelf-margin deltas in the northern Gulf of Mexico: implications for the late Quaternary sea-level elevation at the culmination of the last glacial maximum. Baton Rouge Geological Society (invited talk).
Richmond, R.V., Bart, P.J., and Anderson, J.B., Systems tract relationships on a low subsidence shelf: offshore eastern Alabama/northwest Florida, AAPG Annual meeting San Antonio, Tx,
McKowen, H.A., Bart, P.J., Evolution of the Apalachicola Delta: The last glacial eustatic cycle, Gulf Coast Association of Geological Societies Annual meeting, Lafayette, La
DeBatist, M., Bart, P.J., Jokat, W., Large-scale retrogressive mass wasting of Crary Trough Mouth Fan, Weddell Sea, Antarctica and Global Change Symposium, Hobart, Tasmania, Australia
Bart, P.J., Anderson, J.B., Pleistocene lowstands on the Alabama/west Florida continental shelf: implications for the importance of shelf-edge fluvial incision as an initiator of slope-canyons, AAPG Annual meeting, Salt Lake City, Utah
Bart, P.J., Richmond, R.V., Anderson, J.B., Depositional morphology on the Alabama/west Florida shelf-margin depositional systems: implications for Pleistocene rates of relative sea level fall, GCAGS Annual meeting, Corpus Christi TX
Bart, P.J., and Anderson, J.B., Minimal fluvial/interfluve degradation differentials of Alabama/west Florida shelf margin depositional systems during Pleistocene eustatic lowstands, SEPM Conference Sicily, Italy
Bart, P.J., Keen, R., Kooper, B., Near-surface stratigraphic evolution of Niger shelf margin delta/upper slope at OPL220: Implications for exploration targets, AAPG Annual meeting, Dallas TX
Bart, P.J., and Anderson, J.B., Morphology and seismic stratigraphy of late Pleistocene deltas: possible pathways of downslope transport, GSA Annual meeting, New Orleans, La
Bart, P.J., Trincardi, F.T., Shipp, S.S., Anderson, J.B., Ice streams as sediment point sources for Pliocene to Quaternary deposition: Western Ross Sea, Antarctica, VII International Symposium of Antarctic Earth Sciences
Bart, P.J., and Anderson, J.B., Headward-eroding dendritic fingers of DeSoto Canyon: capture of shelf-sequestered sands, SEPM Annual meeting, St. Petersburg, Fla
Bart, P.J., and Anderson, J.B., Development of Northern Antarctic Peninsula shelf during a transition from an active to passive margin setting, GSA Annual meeting, Seattle, WA
Bart, P.J., DeBatist, M. and Miller, H., Neogene collapse of glacially-deposited, shelf-edge deltas in Weddell Sea: relationships between deposition during glacial periods and sub-marine fan development, The Antarctic Offshore Acoustic Stratigraphy Project Symposium, Siena, Italy
Bart, P.J., and Anderson, J.B., Glacial History of the Antarctic Peninsula Continental Shelf, The Antarctic Offshore Acoustic Stratigraphy Project Symposium, Siena, Italy
Bart, P.J., and Anderson, J.B., Seismic expression of depositional sequences associated
with the expansion and contraction of ice sheets on the northwestern Antarctic Peninsula
continental shelf, Siliciclastic continental shelves, Gent, Belgium
Bart, P.J., Anderson, J.B., Sirigan, F.S. and Shipp, S.S., Seismic stratigraphic record
of decoupling of marine-based ice sheets related to rapid sea level rise, GSA Annual
meeting, New Orleans