Publisher
The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.Abstract
The Magellan radar imager detected approximately 60 dark (i.e. low backscatter cross section) parabola-shaped features on the surface of Venus; each parabola is oriented with the open end toward the west and envelopes an impact crater near its "focus." In this thesis, I use a model of parabola formation to fit the 58 Venusian parabolas observed to date, as well as 9 circular features that are similar to the parabolas. I achieve good results for ∼65% of the 41 parabolas that meet the conditions for the model to apply. As a result of modeling the parabolas, I derive a quantitative description of the distribution of small (∼1 cm to ∼1 μm in diameter) impact ejecta over a planetary surface. My results agree well with the distribution of fine impact ejecta derived for the Terrestrial impact crater Chicxulub. In addition, these results lead to a method for estimating the quantity of fine-grained material available on Venus for surface transport processes such as saltation.Type
textThesis-Reproduction (electronic)
Degree Name
M.S.Degree Level
mastersDegree Program
Graduate CollegePlanetary Sciences