A Morphological and Spatial Analysis of Volcanoes on Venus.

Venus is home to many thousands of volcanic landforms that range in size from much less than 5 km to well over 100 km in diameter. Volcanism is clearly a major, widespread process on Venus, and is a principal expression of the planet's secular loss of interior heat. Without sufficient in situ data to clearly determine its internal structure, we can use the morphological and spatial properties of volcanoes across the planet to help place constraints on our understanding of the volcanic characteristics and history of Venus. With the Magellan synthetic‐aperture radar full‐resolution radar map left‐ and right‐look global mosaics at 75 m‐per‐pixel resolution, we developed a global catalog of volcanoes on Venus that contains ∼85,000 edifices, ∼99% of which are <5 km in diameter. We find that Venus hosts far more volcanoes than previously mapped, and that although they are distributed across virtually the entire planet, size–frequency distribution analysis reveals a relative lack of edifices in the 20–100 km diameter range, which could be related to magma availability and eruption rate. Through spatial density analysis of volcanoes alongside assessments of geophysical data sets and proximal tectonic and volcanic structures, we report on the morphological and spatial patterns of volcanism on Venus to help gain new insights into the planet's geological evolution. Plain Language Summary: There are many thousands of volcanoes on the surface of Venus. These volcanoes provide clues into the interior properties of the planet, properties that are otherwise largely inaccessible to us at present. We used the Magellan synthetic aperture radar imagery to catalog volcanoes across Venus at a global scale. Our resulting database contains ∼85,000 volcanoes, ∼99% of which are less than 5 km in diameter. Although there are volcanoes across almost the entire surface of the planet, there seem to be relatively fewer volcanoes in the 20–100 km diameter range, which may be a function of magma availability and eruption rate. Patterns in spatial clustering of volcanoes in conjunction with geophysical data sets and proximal tectonic and volcanic structures can reveal the nature and distribution of volcanic landforms on Venus. Key Points: We present a new global catalog of volcanoes on Venus that includes ∼85,000 edifices, ∼99% of which are <5 km in diameterWe developed an automated approach to delineating volcanic fields—high spatial concentrations of small volcanoes—from our catalogThere is a lack of edifices in the 20–100 km dimeter range on Venus [ABSTRACT FROM AUTHOR]