The INGV-PROMUD Project: multidisciplinary monitoring of Mud Volcanoes

Mud volcanoes (MVs) are geological structures built by the ejection of a multiphase mixture, composed of cold gases (principally methane), high salinity waters and clayey sediments, dragging rock fragments at the surface. This mixture ascends along lithological or structural discontinuities, creating features as cones or pools. Beyond MVs role in global warming (they are the second natural methane source), they can be a source for geohazards: their ordinary activity can be interrupted by paroxysmal events, characterized by gas blasts and sudden expulsions of huge amounts of mud, whose fallout and subsequent flow can damage facilities and endangering animal and human lives. In spite of the geo-risk associated to their activity, a surveillance protocol of MVs have never been implemented. Large earthquakes or hydrocarbon exploration drillings have been claimed as possible triggers of MVs paroxysms, but the related scientific debate have not led to unanimous conclusions.

The INGV-PROMUD project (https://progetti.ingv.it/it/promud) is aimed to investigate the indicators of the activity of MVs, with the ultimate goal of individuating possible precursors of paroxysmal events. It is a 3-years (2023-2025) multidisciplinary project, based on data acquired by both permanent networks and spot surveys in two main study sites in Italy: the Salse di Nirano (Northern Apennines, ) and the Maccalube di Aragona (Sicily), both managed as nature reserves by the regional governments of Emilia-Romagna and Sicily, respectively.

Research activities are subdivided in 5 Working Packages (WPs):

 WP1 - Seismology, Tectonics, Tilt, hydrology and vegetation analysis, deals with i) analysis of the background seismic noise wavefield and its role in the identification and monitoring of degassing sources and conduits; ii) response of MVs systems to earthquakes and links with regional tectonic structures; iii) tilt observations and their role in monitoring MVs activity; iv) hydrological regime and its influence on MVs activity; v) evolution of the river network as a consequence of MVs activity; vi) vegetation distribution as a marker of MVs evolution in space and time; vii) radio nuclides emissions by soil driven by MVs activity.

WP2 - Remote Sensing and Topography, performs remote sensing for terrain and surface modelling, aimed to identify deformation patterns related to changes in styles, amplitude and rates of MVs activity. It integrates ground data by GNSS with aerial surveys acquired by UAV, with the aim of identifying possible inflation/deflation cycles as proxies of MVs activity. In addition, historical documents and testimonies from the past will be collected and analysed for reconstructing events occurred also in the pre-instrumental era.

WP3 - Geochemistry, Stratigraphy and Rock Magnetism, aimed to measure flux/composition changes of emitted fluids as a proxy of MVs activity, and includes the study of active microbiological communities. Micropaleontological and stratigraphic study will be applied for depth determination of the mud source. The magnetic properties of mud and of the country rocks will be also studied.  

WP4 – Geophysics, is carrying out resistivity and magnetic surveys, for unravelling the geometry of buried structures.

WP5 - Scientific Outreach, manages the project website, produces multimedia material and performs risk education activities in schools.