The Crystallization of Continental Flood Basalt Lavas: Insights from Textural Studies.

This article focuses on the emplacement and cooling processes of continental flood basalt (CFB) lava flows through a comprehensive analysis of crystal size distributions (CSDs) from multiple global datasets. The study finds that CFB eruptions share textural and eruptive characteristics with modern fissure eruptions, such as those in Iceland, rather than with shield or stratovolcano settings. Using a one-dimensional thermal model, the authors demonstrate that CFB lavas cool significantly faster than predicted by standard conductive cooling models, suggesting that assumptions of instantaneous emplacement are inadequate. They propose that processes like incremental emplacement via inflation, lava lobe breakouts, brecciation, and variable eruption rates—often involving multiple simultaneous vents—are critical to accurately modeling cooling histories and eruption dynamics in large flood basalt provinces. These findings highlight the need for advanced models incorporating these intra-lobe and temporal complexities to better understand the environmental and climatic impacts of CFB volcanism.