Abstract
Recent high resolution, high incidence angle Arecibo radar images of southern Ishtar Terra and flanking plains of Guinevere and Sedna on Venus reveal details of topographic features resolved by Pioneer Venus. The high incidence angles of Arecibo images favor the detection of surface roughness-related features, and complement recently obtained low incidence angle Venera 15/16 images in which changes in surface topographic slope are well portrayed. Four provinces have been defined on the basis of radar characteristics in Arecibo images and topography. Volcanism and tectonism are the dominant processes in the mapped area, which has an average age of about 0.5–1.0 billion years (Ivanov et al., 1986). These processes vary in relative significance in the mapped provinces and it is likely that geologic activity has occurred simultaneously in all four provinces. On the basis of stratigraphic evidence, however, a general sequence is proposed which represents the major activity in each area. The low predominantly volcanic plains of Guinevere and Sedna Planitiae are the relatively oldest terrain. A major region of complex tectonic deformation, the Southern Ishtar Transition Zone, postdates much of the low plains and delineates the steep-sloped flanks of Ishtar Terra. Lakshmi Planum is characterized by a distinctive volcanic style (large low edifices, calderas, flanking plains) and at least in part postdates the Southern Ishtar Transition Zone. Relatively recent plains-style volcanism occurs locally in Sedna Planitia and embays the Southern Ishtar Transition Zone. Compressional deformation appears to dominate the mountains of the Ishtar plateau, but the nature of the tectonic deformation in the Southern Ishtar Transition Zone is very complex and likely represents a combination of extension, compression and strikeslip deformation. Arecibo data reveal additional coronae in the lowlands, suggesting that corona formation is an even more widespread process than indicated by the Venera data.
Article PDF
Similar content being viewed by others
References
Barsukov, V. L., Basilevsky, A. T., Pronin, A. A., Kryuchkov, V. P., Nikolaeva, O. V., Chernaya, I. M., Burba, G. A., Bobina, N. N., Shashkina, V. P., Markov, M. S., and Sukhanov, A. L.: 1984, f‘Geology of Venus from the Results of Analysis of Radar Images Taken by Venera 15 and Venera 16 Probes — Preliminary Data’, Geokhimiya 12, 1811–1820.
Barsukov, V. L., Basilevsky, A. T., Burba, G. A., Bobina, N. N., Kryuchkov, V. P., Kuzmin, R. O., Nikolaeva, O. V., Pronin, A. A., Ronca, L. B., Chernaya, I. M., Shashkina, V. P., Garanin, A. V., Kushky, E. R., Markov, M. S., Sukhanov, A. L., Kotelnikov, V. A., Rzhiga, O. N., Petrov, G. M., Alexandrov, Yu. N., Sidorenko, A. I., Bogomolov, A. F., Skrypnik, G. I., Bergman, M. Yu., Kudrin, L. V., Bokshtein, I. M., Kronrad, M. A., Chochia, P. A., Tyuflin, Yu. S., Kadnichansky, S. A., and Akim, E. L.: 1986, ‘The Geology and Geomorphology of the Venus Surface as Revealed by the Radar Images Obtained by Veneras 15 and 16’, J. Geophys. Res. 91, D378-D398.
Basilevsky, A. T., Bobina, N. N., Shashkina, V. P., Shkuratov, Yu. G., Kornienko, Yu. V., Usikov, A. Ya., and Stankevich, D. G.: 1982, ‘On Geological Processes on Venus: Analysis of the Relationship between Altitude and Degree of Surface Roughness’, Moon and Planets 27, 63–89.
Basilevsky, A. T., Pronin, A. A., Ronca, L. B., Kryuchkov, V. P., Sukhanov, A. L., and Markov, M. S.: 1986, ‘Styles of Tectonic Deformation on Venus: Analysis of Veneras 15 and 16 Data’, J. Geophys. Res. 91, D399-D411.
Burns, B. A. and Campbell, D. B.: 1985, ‘Radar Evidence for Cratering on Venus’, J. Geophys. Res. 90, 3037–3047.
Campbell, D. B. and Burns, B. A.: 1980, ‘Earth-Based Radar Imagery of Venus’, J. Geophys. Res. 85, 8271–8281.
Campbell, D. B., Head, J. W., Harmon, J. K., and Hine, A. A.: 1983, ‘Identification of Banded Terrain in the Mountains of Ishtar Terra’, Science 221, 644–647.
Campbell, D. B., Head, J. W., Harmon, J. K., and Hine, A. A.: 1984, ‘Venus: Volcanism and Rift Formation in Beta Regio’, Science 226, 167–170.
Crumpler, L. S., Head, J. W., and Campbell, D. B.: 1986, ‘Evidence for Large-scale Horizontal Motions in Northwest Ishtar Terra, Venus, (abstract)’, Lunar Planet. Sci., Suppl. XVII, 1031–1032.
Fisher, P. C., Head, J. W., Zisk, S. H., Grieve, R. A. F., and Sullivan, K.: 1985, ‘Structure of Terrestrial Impact Craters from SIR-B Radar Data: Preliminary Results, (abstract)’, IGARRS Digest 1, 376–377.
Ford, J. P.: 1980, ‘Seaset Orbital Imagery for Geologic Mapping: Tennessee-Kentucky-Virginia’, AAPG Bull. 64, 2064–2094.
Goldstein, R. M., Green, R. R., and Rumsey, H. C.: 1976, ‘Venus Radar Images’, J. Geophys. Res. 81, 4807–4817.
Greeley, R.: 1982, ‘The Snake River Plain, Idaho: Representative of a New Category of Volcanism’, J. Geophys. Res. 87, 2705–2712.
Head, J. W.: 1986, ‘Venus Global Tectonics: Tectonic Style and Evidence for Latitudinal Distribution of Tectonic Features, (abstract)’, Lunar Planet. Sci. XVII, 325–326.
Head, J. W. and Wilson, L.: 1986, ‘Volcanic Processes and Landforms on Venus: Theory, Predictions, and Observations, J. Geophys. Res. 91, 9407–9446.
Head, J. W., Campbell, D. B., and Zisk, S. H.: 1985a, ‘Tectonism and Volcanism on the Southern Slopes of Ishtar Terra, Venus, (abstract)’, Lunar Planet. Sci. XVI, 331–332.
Head, J. W., Peterfreund, A. R., Garvin, J. B., and Zisk, S. H.: 1985b, ‘Surface Characteristics of Venus Derived from Pioneer Venus Altimetry, Roughness and Reflectivity Measurements’, J. Geophys. Res. 90, 6873–6885.
Ivanov, B. A., Basilevsky, A. T., Kryuchkov, V. P., and Chernaya, I. M.: 1986, ‘Impact Craters of Venus: Analysis of Venera 15 and 16 Data’, J. Geophys. Res. 91, D413-D430.
Masursky, H., Eliason, E., Ford, P. G., McGill, G. E., Pettengill, G. H., Schaber, G. G., and Schubert, G.: 1980, ‘Pioneer Venus Radar Results: Geology from Images and Altimetry’, J. Geophys. Res. 85, 8232–8260.
McGill, G. E., Steenstrup, S. J., Barton, C., and Ford, P. G.: 1981, ‘Continental Rifting and the Origin of Beta Regio, Venus’, J. Geophys. Res. Lett. 8, 737–740.
McGill, G. E., Warner, J. L., Malin, M. C., Arvidson, R. E., Eliason, E., Nozette, S., and Reasenberg, R. D.: 1983, Topography, Surface Properties and Tectonic Evolution, in D. M. Hunten, L. Colin, and T. M. Donahue (eds.), Venus, Univ. Arizona Press, Tucson, pp. 69–130.
Pettengill, G. H., Eliason, E., Ford, P. G., Loriot, G. B., Masursky, H., and McGill, G. E.: 1980, ‘Pioneer Venus Radar Results: Altimetry and Surface Properties’, J. Geophys. Res. 85, 8261–8270.
Phillips, R. J. and Malin, M. C.: 1983, The Interior of Venus and Tectonic Implications, in D. M. Hunten, L. Colin, and T. M. Donahue (eds.), Venus, Univ. Arizona Press, Tucson, pp. 159–214.
Phillips, R. J., Kaula, W. M., McGill, G. E., and Malin, M. C.: 1981, ‘Tectonics and Evolution of Venus’, Science 212, 879–887.
Sharpton, V. L. and Head, J. W.: 1985, ‘Analysis of Regional Slopes on Venus and Earth’, J. Geophys. Res. 90, 3733–3740.
Solomon, S. C. and Head, J. W.: 1982, ‘Mechanisms for Lithospheric Heat Transport on Venus: Implications for Tectonic Style and Volcanism’, J. Geophys. Res. 87, 9236–9246.
Solomon, S. C. and Head, J. W.: 1984, ‘Venus Banded Terrain: Tectonic Models for Band Formation and their Relationship to Lithospheric Thermal Structure’, J. Geophys. Res. 89, 6885–6897.
Stofan, E. R., Head, J. W., and Campbell, D. B.: 1985a, ‘Multiple Ring Features in Themis Regio: Evidence for Endogenic Origin, (aabstract)’, Lunar Planet. Sci. XVI, 825–826.
Stofan, E. R., Head, J. W., and Campbell, D. B.: 1985b, ‘Circular Mountainous Structures on Venus: Evidence for Volcanic Origin’, MSc thesis, Brown University, pp. 2–41.
Stofan, E. R., Head, J. W., Campbell, D. B., Zisk, S. H., Bogomolov, A. F., Rzhiga, O. N., Basilevsky, A. T.: 1986, ‘Beta Regio Rift Zone: Analysis of Arecibo and Venera 15/16 Data, (abstract)’, Lunar Planet. Sci., Suppl. XVII, 1035–1036.
USGS Topographic Map of Venus: 1984, v 50M 6/60 RT.
Walker, G. P. L.: ‘Length of Lava Flows’, Phil. Trans. Roy. Soc. Lond. A274, 107–118.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Stofan, E.R., Head, J.W. & Campbell, D.B. Geology of the southern Ishtar Terra/Guinevere and Sedna Planitae region on Venus. Earth Moon Planet 38, 183–207 (1987). https://doi.org/10.1007/BF00119682
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00119682