Northward migration of the Javanese volcanic arc along thrust faults

East Java is characterised by a complex interaction of volcanic and tectonic processes it marked isolated eruptive centres scattered across the back-arc sedimentary basins. In 2006 large sediment hosted geothermal system named Lusi, pierced Kendeng basin in since then continues relentless eruption mud breccia. To investigate spatial structural relationships between arc domains, we perform local earthquake tomography. The inversion regional earthquakes recorded our seismic network (for about two years) shows sharp Vp Vp/Vs transitions. We observe reduction P-wave velocities high ratio Our study highlights clear connection plumbing northern province. propose conceptual model suggesting that magmas hydrothermal fluids may migrate from middle to upper crust into basins capitalising on existing thrust faults. Such low angle faults, promoted compressional regime region, link magmatic domain provinces. This process represent early phase migration when magma-derived are focused fractured permeable geological structures. would not only help understand occurrence abundant mantle-derived sampled back-arc, but also consistent with hybrid systems piercing environments Java.