Abstract
Monogenetic and polygenetic volcanism can coexist and even transition from one style to another over the lifespan of a volcanic system. The dynamic mechanisms underlying this duality are functions of tectonic and magmatic drivers. The interplay between these factors is still poorly understood and requires spatiotemporal investigations of complex magmatic systems. Understanding this interplay is crucial for improving our ability to assess volcanic products, predict eruption behavior, and ultimately enhance hazard forecasting. The Dunedin Volcanic Group (DVG) serves as a natural laboratory to study the interplay between monogenetic and polygenetic volcanism, capturing the full lifespan of an intraplate volcanic province from its onset to cessation, including periods where these systems coexisted. This study examines the magmatic and tectonic processes of the DVG, which includes the Waipiata Volcanic Field (WVF) and the Dunedin Volcano (DV). The simultaneous magmatic climax of the WVF (~ 16–14 Ma) and the emergence of the DV reveal interconnected magmatic systems. This study identifies three types of magmatic plumbing system development: (1) crustal-differentiated development, with magmatic activity shifting from deep to shallow levels, influenced by NE-striking faults (transitioning from extensional to compressive) and increased magma supply; (2) mantle-differentiated development, characterized by sustained monogenetic activity, influenced by NW-striking compressive faults and local stresses; and (3) undifferentiated development, with persistent but minimal changes for about 15 Myr, independent of tectonic shifts. These findings offer new insights into volcanic evolution, hazard assessment, and eruption forecasting in such distributed volcanic fields.