Magmatic history of the BAT region of Venus: new constraints from the dyke swarm record

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On Venus all basaltic magmatism is intraplate and I propose to provide new insights into the magmatic record of the BAT (Beta Atla Themis) region of Venus by applying concepts being developed for the class of terrestrial intraplate events known as Large Igneous Provinces (LIPs). The BAT is the most significant region on Venus in terms of the abundance of its magmatic features (plume-scale volcanic edifices), scale of rifting and relatively young age. With huge volumes (up to millions of cubic kilometres) and short duration (often emplaced in less than a million years), terrestrial LIPs and their regional dyke swarms are linked to plumes arising from the deep mantle, and associated with the breakup of supercontinents. I propose to apply several key concepts from the terrestrial LIP record to intraplate magmatism on Venus: 1) Regional Stratigraphic Marker. Given their regional extent (up to >3000 km in radius) and short duration of emplacement, major dyke swarms on both Earth and Venus are an efficient regional stratigraphic marker, providing relative ages with respect to the units they cut and are crosscut by. 2) Unit Correlation. On Earth, erosion and plate tectonics have fragmented LIPs into widely separated units (dykes, sills, layered intrusions, remnant flood basalts, and associated carbonatites and kimberlites) that can be correlated using U-Pb geochronology. On Venus, it is predicted that units (volcanic edifices, canali, shield fields, dyke swarms, plains units) can similarly be grouped into discrete large-extent intraplate events (of LIP scale)—through detailed mapping of dyke swarms and their interactions with other units. 3) Hotspot tracks. As magmatic centres are identified and their relative ages are assessed it should be possible to identify any regional trends marking hotspot trails. 4) LIPs and rifting. Comparison of crosscutting relationships between dyke swarms and rifts provide insight into the timing and duration of rifting. This is particularly important given scale of rifts, up to 10,000 km long. The methodology is to use remote sensing data (from the Magellan radar spacecraft and the current multi-sensor Venus Express spacecraft) and apply image processing methodologies used by the planetary science community as well as new approaches with a focus on the Beta-Atla-Themis (BAT) region. The plan is to have one PhD and two MSc students, with the overall goal to produce a comprehensive assessment of magmatic history in the BAT region that integrates the dyke swarm (graben-fissure system) record with mapping of rifts and volcanic features in the region (volcanic edifices, large lava flow fields, large corona, shield plains, and canali).