Research
Interests
Dr. Jack Holt employs airborne
geophysical techniques to study ice-covered regions of Earth and Mars. He has
led five field expeditions to Antarctica since 1998 using a
multi-instrumented Twin Otter to map the ice and features
buried beneath the ice and is currently preparing for a new expedition to
begin in December, 2008 using a new, longer-range platform, the Basler BT-67, a modernized,
turbine-powered DC-3 airframe.
In early 2007 Holt was selected as a Participating Scientist on the SHARAD
instrument team of Mars Reconnaissance Orbiter. so he has
been selecting new data acquisition targets on Mars and analyzing the results
using techniques developed for UTIG’s Antarctic studies.
In Antarctica, Holt is using airborne
gravity and magnetics in conjunction with subglacial topography from radar
sounding to delineate crustal boundaries and characterize active tectonics in
the Amundsen Sea Embayment of West Antarctica. The glaciers of this basin
appear to be losing more mass as a result of climate change than any others
in Antarctica. The basin is also characterized by the highest estimated
geothermal flux in Antarctica, so the ice dynamical response to the
geological boundary conditions of this region may dictate West Antarctica's
contribution to global sea level change.
He is also using airborne geophysics
in Antarctica to develop radar analysis techniques for similar environments
on Mars. The first data set for this project was collected using a 60 MHz
(5-meter wavelength) radar sounder, a result of the Advanced Technology Radar
Sounding (ATRS) project at UTIG. This work
contributes to the effort to find subsurface water on Mars, which is the
highest priority for NASA and ESA missions with the goal of finding evidence
for current or past life on the red planet. The next goal is to implement new radars at SHARAD and
MARSIS frequencies (20 MHz and 5 MHz, respectively) to acquire data over
Antarctic targets including ice cores sites to correlate internal radar
layering at the different frequencies with ice dielectric properties. This
should help us better understand radar data from MARS and plan for future
missions.
Related to these activities, Dr. Holt
is pursuing the use of radar sounding for hydrology in temperate
climates. In the fall of 2008, he is co-teaching a new course at UT
called Hydrogeophysics, with Dr. Jack Sharp of DGS.
And not to leave anything
out, Holt is the Director of the Paleomagnetism Laboratory of the University of Texas
and has recently overseen a complete upgrade of the sample handling,
demagnetization and data acquisition/analysis systems in the lab.
Current
Research Projects
Publications
(refereed)
Young, D. A., S. D. Kempf, D. D. Blankenship, J. W. Holt, and D. L. Morse (2008), New airborne laser altimetry over the
Thwaites Glacier catchment, West Antarctica, Geochemistry, Geophysics,
Geosystems, 9, Q06006, http://dx.doi.org/10.1029/2007GC001935
Diehl, T. M., J. W. Holt, D. D.
Blankenship, D. A. Young, T. A. Jordan, and F. Ferraccioli (2008), First
airborne gravity results over the Thwaites Glacier catchment, West
Antarctica, Geochemistry, Geophysics, Geosystems, 9, Q04011, http://dx.doi.org/10.1029/2007GC001878
Phillips, R.J., Zuber, M.T., Smrekar. S.E., - - -, Holt, J.W., et al. (2008) Mars North Polar Deposits:
Stratigraphy, Age, and Geodynamical Response, Science, 320,
1182-1185, http://dx.doi.org/10.1126/science.1157546
Kirschvink, J.
L., R. E. Kopp, T. D. Raub, C. T. Baumgartner, and J. W. Holt (2008), Rapid, precise, and
High-sensitivity acquisition of paleomagnetic and rock-Mmgnetic data:
Development of a low-noise automatic sample changing system for
superconducting rock magnetometers, Geochemistry, Geophysics,
Geosystems, 9, Q05Y01, http://dx.doi.org/10.1029/2007GC001856
Carter, S.,
D.D. Blankenship, M.E. Peters, D.A. Young, J.W. Holt, and D.L. Morse (2007), Radar-based
subglacial lake classification in Antarctica, Geochemistry, Geophysics,
Geosystems, 8, http://dx.doi.org/10.1029/2006GC001408
Peters, M.E.,
D.D. Blankenship, S.P. Carter, D.A. Young, S.D. Kempf and J.W. Holt (2007), Along-Track Focusing of
Airborne Radar Sounding Data From West Antarctica for Improving Basal
Reflection Analysis and Layer Detection, IEEE Transactions On Geoscience
and Remote Sensing,
45(9), pp. 2725-2736, http://dx.doi.org/10.1109/TGRS.2007.897416
Peters, M.E., D.D. Blankenship, D.E. Smith, J.W. Holt and S.D. Kempf (2007), The Distribution and Classification of Bottom
Crevasses from Radar Sounding of a Large Tabular Iceberg, IEEE
Geoscience and Remote Sensing Letters, 4
(1), p. 142-146, http://dx.doi.org/10.1109/LGRS.2006.887057
Seu, R. R., J. Phillips, - - - J.W. Holt, et al., Accumulation and erosion of Mars south
polar layered deposits from subsurface radar sounding, Science,
317, 1715 - 1718, http://dx.doi.org/10.1126/science.1144120,
2007
Holt, J.W., T.G.
Richter, S.D. Kempf, D.L. Morse, and D.D. Blankenship, Airborne gravity over
Lake Vostok and adjacent highlands, East Antarctica, Geochemistry,
Geophysics, Geosystems, 7, Q11012, http://dx.doi.org/10.1029/2005GC001177,
2006.
Holt, J.W., D.D.
Blankenship, D.L. Morse, D.A. Young, M.E. Peters, S.D. Kempf, T.G. Richter,
D.G. Vaughan, and H.F.J. Corr, New Boundary Conditions for the West Antarctic
Ice Sheet: Subglacial Topography of the Thwaites and Smith Glacier
Catchments. Geophysical Research Letters, 33, L09502, http://dx.doi.org/10.1029/2005GL025561,
2006.
Holt, J.W., M.E.
Peters, S.D. Kempf, D.L. Morse, and D.D. Blankenship, Echo Source Discrimination
in Single-Pass Airborne Radar Sounding Data from the Dry Valleys,
Antarctica: Implications for Orbital Sounding of Mars. Journal
of Geophysical Research, 111, E06S24, doi:10.1029/2005JE002525,
2006.
Holt, J.W., M.E.
Peters, D.L. Morse, D.D. Blankenship, L.E. Lindzey, J.L. Kavanaugh, and K.M.
Cuffey, Identifying and Characterizing Subsurface Echoes in Airborne Radar
Sounding Data From a High-Clutter Environment in Taylor Valley, Antarctica, Eleventh
International Conference on Ground Penetrating Radar, 19-22 June, 2006,
Columbus, Ohio, 5 pp.., 2006.
Vaughan, D.G., H.F.J. Corr, F. Ferraccioli, N. Frearson,
A. O'Hare, D. Mach, J.W. Holt, D.D.
Blankenship, D.L. Morse, and D.A. Young, New boundary conditions for the West
Antarctic ice sheet: Subglacial topography beneath Pine Island Glacier,
Geophysical Research Letters, 33, L09501,
doi:10.1029/2005GL025588, 2006.
Filina, I.Y, D.D. Blankenship, L. Roy, M.K. Sen,
T.G. Richter and J.W. Holt,
Acquisition and analysis of airborne gravity data over subglacial lakes in
East Antarctica, in: Futterer, D.K., D. Damaske, G. Kleinschmidt,
H. Miller, F. Tessensohn, eds., Antarctica: Contributions to Global Earth
Sciences, Springer Publishing House, Berlin Heidelberg New York,
pp. 129-134, 2006.
Studinger, M., R.E. Bell, G.D. Karner, A.A. Tikku, J.W.
Holt, D.L. Morse, T.G. Richter, S.D.
Kempf, M.E. Peters, D.D. Blankenship, Ice cover, landscape setting, and
geological framework of Lake Vostok, East Antarctica. Earth and Planetary
Science Letters, 205(3-4): pp. 195-210, 2003.
Richter, T.G., J.W. Holt, and D.D. Blankenship, Airborne Gravimetry Over The Antarctic Ice
Sheet, in Proceedings of the International Symposium on Kinematic Systems
in Geodesy, Geomatics and Navigation, Banff, Canada, 2001.
Holt, J.W., E.W.
Holt, and J.M. Stock, An age constraint on Gulf of California rifting from
the Boleo Copper District, Baja California Sur, Mexico, GSA Bulletin,
v. 112(4), pp. 540-549, 2000.
Holt, J.W., J.L.
Kirschvink and F. Garnier, Geomagnetic field inclinations for the past 400
kyr from the 1 km core of the Hawaii Scientific Drilling Project, Journal
of Geophysical Research, 101 (B5), pp. 11,655-11,663, 1996.
Holt, J.W. and
J.L. Kirschvink, The upper Olduvai reversal from Death Valley,
California: A fold test of transitional directions, Earth and
Planetary Science Letters, 133, pp. 475-491, 1995.
Quidelleur, X., J. Holt, and J.P. Valet, Confounding influence of magnetic fabric on
sedimentary records of a field reversal, Nature, 374, pp.
246-249, 1995.
Kwok, R., E.J.M. Rignot, J. Way, A. Freeman and J. Holt, Polarization signatures of frozen and thawed
forests of varying environmental state, IEEE Transactions on Geoscience
and Remote Sensing, 32 (2), pp. 371-381, 1994.
Jack's UTIG Publications (List)
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