Spatial Distribution and Evolution of Volcanic Centers in Ulfrun and Beta Regiones on Venus

Based on radar images and topographic data from the Magellan mission, a comparative study of coronae and large volcanoes in Ulfrun and Beta Regiones on Venus has been performed. The geological context of the areas, the spatial distribution of volcanic centers, the morphology of coronae and large volcanoes, and the stratigraphic relationships between them and the surrounding structures are considered. It is shown that in Ulfrun Regio, central volcanism is closely associated with rift zones, whereas in Beta Regio it also occurs outside of rift-related settings. Morphological comparison shows that coronae in both study areas have a similar set of structural elements but differ in the expression of radial deformation and the scale of lava fields. Large volcanoes in both areas are associated with extensive lava fields; however, in Ulfrun Regio they are more often confined to rift zone branches, while in Beta Regio individual centers demonstrate more independent development. The obtained data indicate a multi-stage evolution of central volcanism and allow the differences between the areas to be interpreted as a result of different structural controls and crustal structure.