Show simple item record

dc.contributor.authorGanesh, I.
dc.contributor.authorCarter, L.M.
dc.contributor.authorHenz, T.N.
dc.date.accessioned2022-11-23T18:21:19Z
dc.date.available2022-11-23T18:21:19Z
dc.date.issued2022
dc.identifier.citationGanesh, I., Carter, L. M., & Henz, T. N. (2022). Radar Backscatter and Emissivity Models of Proposed Pyroclastic Density Current Deposits on Venus. Journal of Geophysical Research: Planets, 127(10).
dc.identifier.issn2169-9097
dc.identifier.doi10.1029/2022JE007318
dc.identifier.urihttp://hdl.handle.net/10150/666911
dc.description.abstractMagellan synthetic aperture radar observations of Venus revealed a small number of deposits in the highland regions that were suggested to have formed from pyroclastic density currents. Studying these deposits is useful for understanding the nature of pyroclastic activity and eruptive history on Venus. The proposed pyroclastic deposits occupy the uppermost unit in local stratigraphy and are found near exceptionally high reflectivity ((Formula presented.) ∼0.6) units in the highlands. Their radar properties include high copolarized backscatter (∼−8 to −15 dB) and moderate emissivity values (∼0.70–0.88) in the 12.6 cm wavelength Magellan data acquired at incidence angles between ∼15° and 45°. We aim to characterize the structure of these deposits by modeling the observed backscatter and emissivity as a function of different physical and dielectric properties and shallow subsurface stratigraphy. Three different physical scenarios focusing on three different scattering mechanisms—surface scattering, subsurface scattering from buried dielectric horizons, and volume scattering from buried, distributed scatterers—are considered. By comparing the model results to Magellan observations, we narrow down likely pyroclastic deposit structures. We show that the deposits are likely analogous to dense, welded ignimbrites with high surface roughness. We also investigate other possible but less likely scenarios of a thin, low-density, low-loss mantling pyroclastic deposit on top of high reflectivity units and a thick, low-density, low-loss deposit with ∼5–10 volume % of scatterers of sub-wavelength size. Future multiwavelength, multipolarization radar observations from VERITAS and EnVision may enable unambiguous characterization of these deposits. © 2022. American Geophysical Union. All Rights Reserved.
dc.language.isoen
dc.publisherJohn Wiley and Sons Inc
dc.rightsCopyright © 2022. American Geophysical Union. All Rights Reserved.
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/
dc.subjectmagellan SAR
dc.subjectpyroclastic deposits
dc.subjectradar scattering
dc.subjectradiometry
dc.subjectvector radiative transfer
dc.subjectVenus
dc.titleRadar Backscatter and Emissivity Models of Proposed Pyroclastic Density Current Deposits on Venus
dc.typeArticle
dc.typetext
dc.contributor.departmentLunar and Planetary Laboratory, University of Arizona
dc.contributor.departmentDepartment of Astronomy, University of Arizona
dc.identifier.journalJournal of Geophysical Research: Planets
dc.description.note6 month embargo; first published: 21 September 2022
dc.description.collectioninformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.
dc.eprint.versionFinal published version
dc.source.journaltitleJournal of Geophysical Research: Planets


Files in this item

Thumbnail
Name:
JGR Planets - 2022 - Ganesh - ...
Embargo:
2023-03-21
Size:
3.811Mb
Format:
PDF
Description:
Final Published Version

This item appears in the following Collection(s)

Show simple item record