Relationship Between Explosive and Effusive Volcanism in the Montes Apenninus Region of the Moon

Lunar Pyroclastic Deposits (LPDs) are sites of explosive volcanism and often occur in areas of effusive volcanism on the Moon. On Earth, it has been observed that most volcanism has both effusive and explosive phases, whereas on the Moon, these two types of volcanism have typically been considered separately. We hypothesize that the relationship between explosive and effusive volcanism on the Moon is similar to what is observed on the Earth, where individual eruptions can experience multiple phases rather than one type of volcanism always preceding another or occurring separately. We present observations from the Moon Mineralogy Mapper detailing compositional relationships between volcanic features in the lunar Montes Apenninus region. We evaluated whether co‐located LPDs and effusive features (e.g., rilles, mare) could have erupted from the same volcanic vent or even at the same time based on their compositional similarities and stratigraphic relationships. We found that the LPDs have varied stratigraphic relationships with co‐located effusive features. We identified LPDs near sinuous rilles that may be related to the formation of the rille, where explosive and effusive volcanism occurred at the same vent (e.g., Mozart Rille), and LPDs that may be unrelated to the rille (e.g., Rimae Bode and Rima Bode LPD). Our results suggest that lunar volcanism can mirror terrestrial volcanism, with explosive and effusive eruptions demonstrating more complex dynamics and relationships than previously thought. This variability suggests that the relationship between LPDs and nearby volcanic features cannot be generalized for studies on their resource potential, eruption styles, or deposit volume. Plain Language Summary Volcanic eruptions can be explosive or non‐explosive (effusive), and sometimes both types of eruptions can be seen at a single volcanic site. This can be interpreted as two types of eruptions happening at the same time from the same vent, happening at the same time from different vents, or happening from the same vent at different times. Having different eruption types is common for volcanoes on Earth and often a volcano will erupt explosively and effusively at the same time. Even though we see signs of explosive and effusive volcanism on the Moon, there is currently no active volcanism to inform how these eruptions are correlated. To study this, we use the Moon Mineralogy Mapper, an instrument that helps identify minerals in the products of explosive volc