Analisi morfometriche di tubi di lava

Lava tubes (also known as pyroducts) are objects of great interest not only for their role in the formation of lava flow fields on Earth but also because these geological features could have important implications for the emplacement of lava terrains across the Solar System. These features have been detected on the surface of Mars and the Moon through satellite imagery as sinuous collapse chains (often interpreted as the surface evidence of subsurface conduits) and present an opportunity to better define whether volcano-speleogenetic processes on Earth can be correlated with similar morphologies on different planetary bodies. Although to date there is not technology to observe the subsurface conduits of other planetary bodies, through the study of terrestrial analogues it is possible to infer the potential lava tube morphologies beneath the surface of Mars and the Moon. Many maps and surveys of lava tubes, collected in regional caving records around the world, show a wide variety of lava tube morphologies. Different authors have proposed several morphometrics indices to describe the genetic features of some particular karst caves. Here there same approach was applied to the lava tubes. Digitizing and collecting lava tube surveys allows us to extract several dimensional parameters and develop a global database. An initial observation of the surveys was necessary to understand qualitative morphological differences, and then morphometric indices were extracted, which were useful to recognize, through a statistical approach, a quantitative relationship between lava tube morphologies and genetic processes, in different volcanic settings. Lava tubes on Earth can have different morphologies and a huge difference in size, potentially associated with specific eruptive (effusion rates, trend and duration of the eruption) or slope parameters. In this work we analyzed and discussed this variability, trying to extrapolate useful information to understand lava tube genetic processes on other planetary bodies.