A snapshot of the transition from monogenetic volcanoes to composite volcanoes: case study on the Wulanhada Volcanic Field (northern China)

Abstract. The transition processes from monogenetic volcanoes to composite are poorly understood. Late Pleistocene Holocene intraplate Wulanhada Volcanic Field (WVF) in northern China provides a snapshot of such transition. Here we present petrographic observations, mineral chemistry, bulk rock major and trace element data, thermobarometry, partial melting model for the WVF evaluate lithology degree mantle source, crystallization conditions, pre-eruptive magmatic occurring within magma plumbing system. far-field effect India–Eurasia collision resulted relatively high (10 %–20 %) carbonate-bearing eclogite (∼ 3 wt % carbonate; Gt/Cpx ≈ 2 : 8, where Gt denotes garnet Cpx clinopyroxene) followed by interaction with ambient peridotite. primary melts ascended depth Moho 33–36 km depth), crystallized olivine, clinopyroxene plagioclase at temperature 1100–1160 ∘C melt water contents 1.1 %–2.3 %. Part interacted lithospheric during ascent, resulting an increase MgO decrease alkaline contents. modified was subsequently directly emplaced into middle crust 23–26 depth) ∘C. same sources migrated upward two-level reservoirs form minerals complex textures (including reverse oscillatory zoning sieve texture). Magma erupted along NE–SW-striking basement fault NW–SE-striking Wulanhada–Gaowusu response combined effects regional tectonic stress replenishment. crustal reservoir may represent volcanoes. It is possible volcano large volumes compositions if continuously supplied source experiences assimilation fractional system depth.