Abstract

Venus surface has been studied extensively using SAR (synthetic aperture radar) -imagery provided by the NASA Magellan mission in 1990–1994. The radar images with ~98% coverage and resolution of ~100 m may be used in order to understand the global suite of surface structures, and to analyze single features and their formation processes using photogeological approaches and methods.

This study recognizes and catalogues four Venusian surface structure types, the coronae, arachnoids, novae and corona-novae. The study goals are:

a) To provide a thorough survey of the four Venusian volcano-tectonic feature groups (characteristics, distribution, measurements of size and location), and to defend the recognization of the feature groups,

a. 596 coronae, 139 arachnoids, 74 novae and 35 corona-novae

b) To present a characterization method that is based on the generalized governing geological units: I — deformation zones, II — plains, III — tessera, and IV — regions with volcanic concentration,

c) To present results on the observations of formational processes:

a. Arachnoids display implications for at least three different formational origin

b. Model of corona-novae formation provides theoretical explanations to meet the observations of the individual features

c. Observations of young arcuate tectonic features on the flanks of some of the volcano-tectonic features located in the rift zone -region

All gathered information supply to the goal of understanding Venus. As a single plate planet without plate tectonics, an alternate heat flow mechanism is in effect. The volcano-tectonic features may be part of the solution.