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

Abstract

Venus boasts an abundance of volcano 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 change subsequent to the emplacement of lava flows within their fracture annuli, pointing to the critical role of volcanism 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 that integrates magmatic processes into geophysical models.

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

“…The Venus topography model, VenusTopo719 (Wieczorek, 2015), and gravity model, MGNP180U (Konopliv et al, 1999), are available through the datasets submodule in SHTools. The Python code SHPointPower for the spherical harmonic analysis is available via GitHub (Tucker, 2023), and GIS shapefiles of the mapped lava flow centerlines are available via Zenodo (Tucker & Dombard, 2023b). The newly identified subsets of divergent and nondivergent coronae are available in Table S1.…”