Distribution of Eruptive Centers on Top of Large Shield Volcanoes in the Inner Solar System: General Classification and Glimpses of Their Subvolcanic Structure

Abstract

AbstractProcesses that occur beneath a planetary surface control the spatial distribution of volcanic features in a volcanic zone. Volcanic vents frequently form clusters and alignments controlled by the lithospheric structure and the stress field. Previous works have determined the influence of stress at different scales in a volcanic area. In this work, we analyze the distribution of volcanic vents on top of shield volcanoes on four different bodies of the Solar System: Pinacate (Earth), Mauna Kea (Earth), Marius Hills (Moon), Mons Rümker (Moon), Olympus Mons (Mars), Kunapipi Mons (Venus), and Var Mons (Venus), to identify characteristics of the volcanic systems and compare their spatial distribution patterns in order to determinate similarities and differences. The Gaussian kernel is the base of the analysis; this method is an exploration tool that generates a sequence of probability density functions (PDFs). Thus, we have constrained the predominant orientations of dikes and the shape, orientation, and location at depth of the magmatic source. Based on our results, we extend the classification of shield volcanoes divided into two main groups: (a) those that grow only under the influence of magmatic stress fields (Marius Hills, Olympus Mons, and Mons Rümker) and (b) those that grow under the influence of external stress fields (Pinacate), to other bodies of the Solar System. Some shield volcanoes present characteristics from both groups (Mauna Kea, Kunapipi Mons, and Var Mons).