Stability and Collapse Analysis of Terrestrial Lava Tubes Under Irregular Shapes: Case Study of Skull and Valentine Caves

Lava tubes have attracted increasing attention from scientists and space industry professionals due to their potential as protective shelters on planetary bodies such as the Moon or Mars as well as for scientific research. This interest has motivated investigations into terrestrial lava tubes as analogs for extraterrestrial caves. In this study, we present the first comprehensive numerical analysis of the stability and collapse geometry of two terrestrial lava tubes, Skull Cave and Valentine Cave, using laser scan data of their interiors and surrounding terrain. Our methodology is based on finite element limit analysis, which can accurately and efficiently replicate the natural and irregular shapes of these caves for stability analysis. We performed additional analyses by varying rock roof thickness and other parameters to validate whether previous findings from studies on artificially generated irregular shapes hold true for actual cave geometries. Our results provide new insights into how natural irregularities in cave geometry influence stability and collapse mechanisms. The results confirm the significant impact of these irregularities and offer a robust approach for assessing cave stability.