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52. The Geographic Distribution of Boulder Halo Craters at Mid-to-High Latitudes on Mars

Author

Rader, L. X, Fassett, C. I, Levy, J. S, King, I. R, Chaffey, P. M, Wagoner, C. M, Hanlon, A. E, Watters, J. L, Kreslavsky, M. A, Holt, J. W, and Dyar, M. D

Subjects
Lunar And Planetary Science And Exploration
Abstract

Extensive evidence exists for ground ice at mid-to-high latitudes on Mars, including results from neutron spectroscopy [1-3], thermal properties [4-5], geomorphology [e.g., 6-9], and the in situ observations of Mars Phoenix [10]. This ground ice has been hypothesized to be emplaced diffusively and fill pores [11], or to have accumulated by ice and dust deposition that draped or mantled the terrain [7, 12]. These two processes are not mutually exclusive; both potentially have occurred on Mars [5]. One of the landforms found in areas where ground ice is common on Mars are boulder halo craters [e.g., 13-15] (Figure 1), which are topographically muted impact craters that are filled by ice-rich regolith. They are outlined by boulders that trace a circular outline of the original crater rim. Boulder halos generally have distinctly higher boulder densities than the surrounding background plains and have few boulders in their interiors. The mechanism of boulder halo crater formation is somewhat uncertain. Our working model is that an impact event occurs with sufficient size to excavate to a depth greater than the boulder-poor, ice-rich soils. Excavated boulders are deposited around the crater's rim and in its proximal ejecta. Quite rapidly [14], the crater becomes infilled by icy soil. Rather than being buried, boulders in the halo remain at the surface, perhaps be-cause they 'float' relative to finer-grained materials [14, 16]. Regardless of the details of this process, the life-time of boulders at the surface is much greater than the timescale needed to remove most of the craters' topography. Physical weathering of rocks must be greatly out-paced by crater infilling (the opposite of what is typical, e.g., on the Moon [17]). The rapidity of this infilling is easiest to understand if icy mantling material is deposited and accumulates, rather than simply being added by pore filling of soils. If this model is correct, boulder halos only form when they excavate rock-producing materials from beneath the upper surface. Thus, the distribution and size of craters that result in boulders halos may provide in-sight into the thickness of the ice-rich surface layer in different locations. Note that this thickness is necessarily that of the ice-rich layer at the time of impact, not at present. This study is an initial survey of boulder halo crater locations in the 50deg to 80degN and 50deg to 80degS latitude bands on Mars.

Published
2017

56. Solar-System-Wide Significance of Mars Polar Science

Author

Smith, Isaac, primary, Calvin, W. M., additional, Smith, D. E., additional, Hansen, C., additional, Diniega, S., additional, McEwen, A., additional, Thomas, N., additional, Banfield, D., additional, Titus, T. N., additional, Becerra, P., additional, Kahre, M., additional, Forget, F., additional, Hecht, M., additional, Byrne, S., additional, Hvidberg, C. S., additional, Hayne, P. O., additional, III, J. W. Head,, additional, Mellon, M., additional, Horgan, B., additional, Mustard, J., additional, Holt, J. W., additional, Howard, A., additional, McCleese, D., additional, Stoker, C., additional, James, P., additional, Putzig, N. E., additional, Whitten, J., additional, Buhler, P., additional, Spiga, A., additional, Crismani, M., additional, Aye, K. M., additional, Portyankina, A., additional, Orosei, R., additional, Bramson, A., additional, Hanley, J., additional, Sori, M., additional, Aharonson, O., additional, Clifford, S., additional, Sizemore, H., additional, Morgan, G., additional, Hartmann, B., additional, Schorghofer, N., additional, Clark, R., additional, Berman, D., additional, Crown, D., additional, Chuang, F., additional, Siegler, M., additional, Dobrea, E. N., additional, Lynch, K., additional, Obbard, R. W., additional, Elmaary, M. R., additional, Fisher, D., additional, Kleinboehl, A., additional, Balme, M., additional, Schmitt, B., additional, Daly, M., additional, Ewing, R. C., additional, Herkenhoff, K. E., additional, Fenton, L., additional, Guzewich, S. D., additional, Koutnik, M., additional, Levy, J., additional, Massey, R., additional, Łosiak, A., additional, Eke, V., additional, Goldsby, D., additional, Cross, A., additional, Hager, T., additional, Piqueux, S., additional, Kereszturi, A., additional, Seelos, K., additional, Wood, S., additional, Hauber, E., additional, Amos, C., additional, Russell, P., additional, Jaumann, R., additional, Michael, G., additional, Conway, S., additional, Khayat, A., additional, Lewis, S., additional, Luizzi, G., additional, Martinez, G., additional, Mesick, K., additional, Montabone, L., additional, Johnsson, A., additional, Pankine, A., additional, Phillips-Lander, C., additional, Read, P., additional, Edgar, L., additional, Zacny, K., additional, McAdam, A., additional, Rutledge, A., additional, Bertrand, T., additional, Widmer, J., additional, Stillman, D., additional, Soto, A., additional, Yoldi, Z., additional, Young, R., additional, Svensson, A., additional, Sam, L., additional, Landis, M., additional, Bhardwaj, A., additional, Chojnacki, M., additional, Kite, E., additional, Thomas, P., additional, Plaut, J., additional, Bapst, J., additional, Milkovich, S., additional, Whiteway, J., additional, Moores, J., additional, Rezza, C., additional, Karimova, R., additional, Mishev, I., additional, Brenen, A. Van, additional, Acharya, P., additional, Chesal, J., additional, Pascuzzo, A., additional, Vos, E., additional, Osinski, G., additional, Andres, C., additional, Neisch, C., additional, Hibbard, S., additional, Sinha, P., additional, Knightly, J. P., additional, Cartwright, S., additional, Kounaves, S., additional, Orgel, C., additional, Skidmore, M., additional, MacGregor, J., additional, Staehle, R., additional, Rabassa, J., additional, Gallagher, C., additional, Coronato, A., additional, Galofre, A. G., additional, Wilson, J., additional, McKeown, L., additional, Oliveira, N., additional, Fawdon, P., additional, Gayathri, U., additional, Stuurman, C., additional, Herny, C., additional, Butcher, F., additional, Bernardini, F., additional, Perry, M., additional, Hu, R., additional, Mukherjee, S., additional, Chevrier, V., additional, Banks, M. E., additional, Meng, T., additional, Johnson, P. A., additional, Tober, B., additional, Johnson, J. C., additional, Ulamsec, S., additional, Echaurren, J. C., additional, Khuller, A., additional, Dinwiddie, C., additional, Adeli, S., additional, Henderson, B. L., additional, Lozano, L. R., additional, Lalich, D., additional, Rivera-Valentín, E., additional, Nerozzi, S., additional, Petersen, E., additional, Foss, F., additional, Lorenz, R., additional, Eigenbrode, J., additional, Day, M., additional, Brown, A., additional, Pajola, M., additional, Karatekin, Ö., additional, Lucchetti, A., additional, Cesar, C., additional, Newman, C., additional, Cave, T. G., additional, Tamppari, L., additional, Mischna, M., additional, Patel, M., additional, Streeter, P., additional, Stern, J. C., additional, and Dundas, C. M., additional

Published
2021
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58. Nuclear pairing from two-body microscopic forces: analysis of the Cooper pair wavefunctions

Author

Finelli P., Maurizio S., and Holt J. W.

Subjects
Physics, QC1-999
Abstract

In a recent paper [1] we studied the behavior of the pairing gaps ΔF as a function of the Fermi momentum kF for neutron and nuclear matter in all relevant angular momentum channels where superfluidity is believed to naturally emerge. The calculations employed realistic chiral nucleon-nucleon potentials [2, 3] with the inclusion of three-body forces and self-energy effects. In this contribution, after a detailed description of the numerical method we employed in the solution of the BCS equations, we will show a preliminary analysis of the Cooper pair wavefunctions.

Published
2015
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60. Surface Clutter Removal in Airborne Radar Sounding Data from the Dry Valleys, Antarctica

Author

Holt, J. W, Blankenship, D. D, Morse, D. L, Peters, M. E, and Kempf, S. D

Subjects
Lunar And Planetary Science And Exploration
Abstract

We have collected roughly 1,000 line-km of airborne radar sounding data over glaciers, rock/ice glaciers, permafrost, subsurface ice bodies, ice-covered saline lakes, and glacial deposits in Taylor and Beacon Valley. These data are being analyzed in order to develop techniques for discriminating between subsurface and off-nadir echoes and for detecting and characterizing subsurface interfaces. The identification of features on Mars exhibiting morphologies consistent with ice/rock mixtures, near-surface ice bodies and near-surface liquid water, and the importance of such features to the search for water on Mars, highlights the need for appropriate terrestrial analogs and analysis techniques in order to prepare for radar sounder missions to Mars. Climatic, hydrological, and geological conditions in the Dry Valleys of Antarctica are analogous in many ways to those on Mars. A crucial first step in the data analysis process is the discrimination of echo sources in the radar data. The goal is to identify all returns from the surface of off-nadir topography in order to positively identify subsurface echoes. This process will also be critical for radar data that will be collected in areas of Mars exhibiting significant topography, so that subsurface echoes are identified unambiguously. The positive detection and characterization of subsurface (including sub-ice) water is a primary goal of NASA's Mars exploration program. Our data over the Dry Valleys provides an opportunity to implement techniques we are developing to accomplish these goals.

Published
2005

61. Echo Source Discrimination in Airborne Radar Sounding Data for Mars Analog Studies, Dry Valleys, Antarctica

Author

Holt, J. W, Blankenship, D. D, Peters, M. E, Kempf, S. D, Morse, D. L, and Williams, B. J

Subjects
Meteorology And Climatology
Abstract

The recent identification of features on Mars exhibiting morphologies consistent with ice/rock mixtures, near-surface ice bodies and near-surface liquid water [1,2], and the importance of such features to the search for water on Mars, highlights the need for appropriate terrestrial analogs in order to prepare for upcoming radar missions targeting these and other water-related features. Climatic, hydrological, and geological conditions in the McMurdo Dry Valleys of Antarctica are analogous in many ways to those on Mars, and a number of ice-related features in the Dry Valleys may have direct morphologic and compositional counterparts on Mars.

Published
2003

67. New Magnetic Anomaly Map of the Antarctic

Author

Golynsky, A. V., Ferraccioli, F., Hong, J. K., Golynsky, D. A., von Frese, R. R. B., Young, D. A., Blankenship, D. D., Holt, J. W., Ivanov, S. V., Kiselev, A. V., Masolov, V. N., Eagles, G., Gohl, K., Jokat, W., Damaske, D., Finn, C., Aitken, A., Bell, R. E., Armadillo, E., Jordan, T. A., Greenbaum, J. S., Bozzo, E., Caneva, G., Forsberg, R., Ghidella, M., Galindo-Zaldivar, J., Bohoyo, F., Martos, Y. M., Nogi, Y., Quartini, E., Kim, H. R., Roberts, J. L., Golynsky, A. V., Ferraccioli, F., Hong, J. K., Golynsky, D. A., von Frese, R. R. B., Young, D. A., Blankenship, D. D., Holt, J. W., Ivanov, S. V., Kiselev, A. V., Masolov, V. N., Eagles, G., Gohl, K., Jokat, W., Damaske, D., Finn, C., Aitken, A., Bell, R. E., Armadillo, E., Jordan, T. A., Greenbaum, J. S., Bozzo, E., Caneva, G., Forsberg, R., Ghidella, M., Galindo-Zaldivar, J., Bohoyo, F., Martos, Y. M., Nogi, Y., Quartini, E., Kim, H. R., and Roberts, J. L.

Abstract

The second generation Antarctic magnetic anomaly compilation for the region south of 60°S includes some 3.5 million line-km of aeromagnetic and marine magnetic data that more than doubles the initial map’s near-surface database. For the new compilation, the magnetic data sets were corrected for the International Geomagnetic Reference Field, diurnal effects, and high-frequency errors and leveled, gridded, and stitched together. The new magnetic data further constrain the crustal architecture and geological evolution of the Antarctic Peninsula and the West Antarctic Rift System in West Antarctica, as well as Dronning Maud Land, the Gamburtsev Subglacial Mountains, the Prince Charles Mountains, Princess Elizabeth Land, and Wilkes Land in East Antarctica and the circumjacent oceanic margins. Overall, the magnetic anomaly compilation helps unify disparate regional geologic and geophysical studies by providing new constraints on major tectonic and magmatic processes that affected the Antarctic from Precambrian to Cenozoic times.

Published
2018

68. New Magnetic Anomaly Map of the Antarctic

Author

Golynsky, A. V., primary, Ferraccioli, F., additional, Hong, J. K., additional, Golynsky, D. A., additional, von Frese, R. R. B., additional, Young, D. A., additional, Blankenship, D. D., additional, Holt, J. W., additional, Ivanov, S. V., additional, Kiselev, A. V., additional, Masolov, V. N., additional, Eagles, G., additional, Gohl, K., additional, Jokat, W., additional, Damaske, D., additional, Finn, C., additional, Aitken, A., additional, Bell, R. E., additional, Armadillo, E., additional, Jordan, T. A., additional, Greenbaum, J. S., additional, Bozzo, E., additional, Caneva, G., additional, Forsberg, R., additional, Ghidella, M., additional, Galindo‐Zaldivar, J., additional, Bohoyo, F., additional, Martos, Y. M., additional, Nogi, Y., additional, Quartini, E., additional, Kim, H. R., additional, and Roberts, J. L., additional

Published
2018
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70. Distribution and Characteristics of Boulder Halos at High Latitudes on Mars: Ground Ice and Surface Processes Drive Surface Reworking

Author

Levy, J. S., primary, Fassett, C. I., additional, Rader, L. X., additional, King, I. R., additional, Chaffey, P. M., additional, Wagoner, C. M., additional, Hanlon, A. E., additional, Watters, J. L., additional, Kreslavsky, M. A., additional, Holt, J. W., additional, Russell, A. T., additional, and Dyar, M. D., additional

Published
2018
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71. An ice age recorded in the polar deposits of Mars

Author

Smith, I. B., Putzig, N. E., Holt, J. W., and Phillips, R. J.

Abstract

Layered ice deposits at the poles of Mars record a detailed history of accumulation and erosion related to climate processes. Radar investigations measure these layers and provide evidence for climate changes such as ice advance and retreat. We present a detailed analysis of observational data that shows ~87,000 km3 of ice have accumulated at the poles since the end of the last ice age, ~370 kyr ago, a volume equivalent to a ~60 cm global layer. The majority of the material accumulated at the north pole. These results provide a means to understand the accumulation history of the polar deposits as related to orbital, Milankovitch cycles and constrain climate models for a better determination of Mars' past and future climates.

Published
2016

74. Preface

Author

Holt, J. W., primary, Kuo, T. T. S., additional, Phua, K. K., additional, Rho, M., additional, and Zahed, I., additional

Published
2017
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75. Radar Subsurface Sounding Over the Putative Frozen Sea in Cerberus Palus, Mars

Author

Orosei, R., Cartacci, M., Cicchetti, A., Federico, C., Flamini, E., Frigeri, A., Holt, J. W., Marinangeli, L., Noschese, R., Phillips, R. J., Picardi, G., Plaut, J. J., Safaeinili, A., Seu, R., PETTINELLI, Elena, Orosei, R., Cartacci, M., Cicchetti, A., Federico, C., Flamini, E., Frigeri, A., Holt, J. W., Marinangeli, L., Noschese, R., Pettinelli, Elena, Phillips, R. J., Picardi, G., Plaut, J. J., Safaeinili, A., and Seu, R.

Published
2007

85. Two independent methods for mapping the grounding line of an outlet glacier – an example from the Astrolabe Glacier, Terre Adélie, Antarctica

Author

Le Meur, E., primary, Sacchettini, M., additional, Garambois, S., additional, Berthier, E., additional, Drouet, A. S., additional, Durand, G., additional, Young, D., additional, Greenbaum, J. S., additional, Holt, J. W., additional, Blankenship, D. D., additional, Rignot, E., additional, Mouginot, J., additional, Gim, Y., additional, Kirchner, D., additional, de Fleurian, B., additional, Gagliardini, O., additional, and Gillet-Chaulet, F., additional

Published
2014
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89. Two independent methods for mapping the grounding line of an outlet glacier – example from the Astrolabe Glacier, Terre Adélie, Antarctica

Author

Le Meur, E., primary, Sacchettini, M., additional, Garambois, S., additional, Berthier, E., additional, Drouet, A. S., additional, Durand, G., additional, Young, D., additional, Greenbaum, J. S., additional, Blankenship, D. D., additional, Holt, J. W., additional, Rignot, E., additional, Mouginot, J., additional, Gim, Y., additional, Kirchner, D., additional, de Fleurian, B., additional, Gagliardini, O., additional, and Gillet-Chaulet, F., additional

Published
2013
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93. Supplementary material to "Bedmap2: improved ice bed, surface and thickness datasets for Antarctica"

Author

Fretwell, P., primary, Pritchard, H. D., additional, Vaughan, D. G., additional, Bamber, J. L., additional, Barrand, N. E., additional, Bell, R., additional, Bianchi, C., additional, Bingham, R. G., additional, Blankenship, D. D., additional, Casassa, G., additional, Catania, G., additional, Callens, D., additional, Conway, H., additional, Cook, A. J., additional, Corr, H. F. J., additional, Damaske, D., additional, Damm, V., additional, Ferraccioli, F., additional, Forsberg, R., additional, Fujita, S., additional, Gogineni, P., additional, Griggs, J. A., additional, Hindmarsh, R. C. A., additional, Holmlund, P., additional, Holt, J. W., additional, Jacobel, R. W., additional, Jenkins, A., additional, Jokat, W., additional, Jordan, T., additional, King, E. C., additional, Kohler, J., additional, Krabill, W., additional, Riger-Kusk, M., additional, Langley, K. A., additional, Leitchenkov, G., additional, Leuschen, C., additional, Luyendyk, B. P., additional, Matsuoka, K., additional, Nogi, Y., additional, Nost, O. A., additional, Popov, S. V., additional, Rignot, E., additional, Rippin, D. M., additional, Riviera, A., additional, Roberts, J., additional, Ross, N., additional, Siegert, M. J., additional, Smith, A. M., additional, Steinhage, D., additional, Studinger, M., additional, Sun, B., additional, Tinto, B. K., additional, Welch, B. C., additional, Young, D. A., additional, Xiangbin, C., additional, and Zirizzotti, A., additional

Published
2012
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94. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica

Author

Fretwell, P., primary, Pritchard, H. D., additional, Vaughan, D. G., additional, Bamber, J. L., additional, Barrand, N. E., additional, Bell, R., additional, Bianchi, C., additional, Bingham, R. G., additional, Blankenship, D. D., additional, Casassa, G., additional, Catania, G., additional, Callens, D., additional, Conway, H., additional, Cook, A. J., additional, Corr, H. F. J., additional, Damaske, D., additional, Damm, V., additional, Ferraccioli, F., additional, Forsberg, R., additional, Fujita, S., additional, Gogineni, P., additional, Griggs, J. A., additional, Hindmarsh, R. C. A., additional, Holmlund, P., additional, Holt, J. W., additional, Jacobel, R. W., additional, Jenkins, A., additional, Jokat, W., additional, Jordan, T., additional, King, E. C., additional, Kohler, J., additional, Krabill, W., additional, Riger-Kusk, M., additional, Langley, K. A., additional, Leitchenkov, G., additional, Leuschen, C., additional, Luyendyk, B. P., additional, Matsuoka, K., additional, Nogi, Y., additional, Nost, O. A., additional, Popov, S. V., additional, Rignot, E., additional, Rippin, D. M., additional, Riviera, A., additional, Roberts, J., additional, Ross, N., additional, Siegert, M. J., additional, Smith, A. M., additional, Steinhage, D., additional, Studinger, M., additional, Sun, B., additional, Tinto, B. K., additional, Welch, B. C., additional, Young, D. A., additional, Xiangbin, C., additional, and Zirizzotti, A., additional

Published
2012
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97. Radar subsurface sounding over the putative frozen sea in Cerberus Palus, Mars

Author

Orosei, R, primary, Cartacci, M, additional, Cicchetti, A, additional, Noschese, R, additional, Federico, C, additional, Frigeri, A, additional, Flamini, E, additional, Holt, J W, additional, Marinangeli, L, additional, Pettinelli, E, additional, Phillips, R J, additional, Picardi, G, additional, Seu, R, additional, and Plaut, J J, additional

Published
2010
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