Spherical-Harmonic Distribution Analysis of Coronae in Relation to Volcanic Features on Venus

Venus boasts an abundance of volcanoes and volcano-like structures. Synthetic aperture radar images of the surface have revealed extensive evidence of volcanism, including lava flows and edifices. Volcanic activity is further supported by crater statistics, and analysis of topography and gravity data. Unique to Venus, coronae are quasi-circular volcano-tectonic features exhibiting diverse volcanic characteristics. Despite this, volcanism is often under-represented in formation models. We identify a new subset of coronae that display topographic changes subsequent to the emplacement of lava flows within their fracture annuli, pointing to the critical role of volcanic and magmatic processes in the formation of these coronae. Through spherical-harmonic distribution analysis, we find that this new subset is spatially related to the full coronae database, pointing to an intrinsic process of coronae formation. Furthermore, coronae exhibit strong correlations and similar spectral shapes at low spherical harmonic degrees with large volcanoes, suggesting a shared geodynamic origin. Our findings underscore the pivotal role of volcanism in coronae formation and highlight the need for future research to integrate magmatic and volcanic processes more comprehensively into geophysical models. Such models would better capture the complex interactions between volcanic emplacement, magmatic activity, and lithospheric dynamics on Venus. Venus's surface has a large number of volcanoes and features with characteristics similar to volcanoes. Radar imagery of the surface reveals signs of volcanism such as lava flows and volcanically built mountains. A unique volcanic feature, found only on Venus, are coronae, which have circular fractures and various types of associated volcanic activity. Explanations of how coronae form often do not consider the role of volcanic activity. In our study, we identify a new group of coronae that have undergone changes in topography after lava erupted and flowed over them, which has been interpreted as volcanism having a central role in corona formation. The locations of this subset of coronae on the surface fit well with all other coronae, suggesting that the processes that caused this topographic change occur throughout the corona population and are a basic part of how all coronae form. Additionally, we find that coronae have a similar pattern on the surface to large volcanoes, which indicates a shared volcanically based origin. Our work shows that in order to better understand coronae, we need to consider the role of volcanism in their formation. A new subset of coronae shows topographic changes post-lava flow emplacement Spectral analysis reveals strong long-wavelength similarities between coronae and large volcanoes Volcanism plays a crucial role in corona formation and should be considered central in future models of formation