Buried Silicic Volcanoes Discovered in the Gruithuisen Region on the Moon

Mons Gruithuisen is a rare example of nonmare silicic volcanoes on the Moon. We have conducted analyses of the topography, chemical compositions, and subsurface structures of the Gruithuisen region based on remote sensing and gravity data. Our findings include presence of newly detected magma chambers in addition to the previously identified silicic domes in Gruithuisen Region. Our analysis suggests that multiple phases of silicic volcanism have occurred in the Gruithuisen region. The subsurface density revealed by the gravity data also suggests the presence of several low‐density masses in the crust. These early‐formed silicic volcanoes at low elevations are overlain by later‐emplaced mare basalts, however, the side slopes of these volcanoes are not covered by mare basalts, and the low‐FeO abundance material is exposed on the lunar surface. Plain Language Summary Silicic volcanoes are uncommon on the Moon. We have conducted analyses of the shallow structures and surface features of the Gruithuisen region using remote sensing and gravity data. Our findings reveal the presence of silicic volcanoes that were covered by mare basalt. The topography, chemical composition, and density structure of the lunar crust in the Gruithuisen region suggest the presence of buried silicic volcanoes. The smooth surface units in the region are not ejecta from Imbrium basin, but ancient silicic volcanoes. The surfaces of these silicic volcanoes have been contaminated with mare basalt. Key Points Buried silicic volcanoes have been identified in the Gruithuisen region on the Moon Gravity models reveal the subsurface structures of silicic volcanoes Silicic volcanoes that formed early in the Gruithuisen region were characterized by low elevations and were later covered by mare basalt