Integrated observations and monitoring solutions for exploration and sustainable exploitation of marine abiotic resources
Hydrocarbons are organic compounds that contain only carbon and hydrogen atoms. Marine environments are ideal for their formation, because organic matter rapidly undergoes anaerobic degradation while high and fast sedimentation rates, typical of marine settings such as the Adriatic Sea, favor rapid burial and decomposition of organic matter. Hydrocarbon generation can be either microbial or thermic, at different temperatures and depths. Hydrocarbons tend to migrate to shallower sedimentary horizons, giving rise to seafloor features such as pockmarks and mud volcanoes with varying scales. When the flow is sufficiently high, hydrocarbons escape the seabed and form gas plumes in the water column. The plumes can be detected as density anomalies by marine acoustic and geophysical sensors, that combined with geochemical and hydrological data, allow to quantify the upward flux of gas.
Hydrocarbon seepage is overlooked in the marine environment, mostly due to the lack of adequate space-time resolution environmental monitoring data that consider also the climate variability. This contribution is about the set-up of relocatable, customizable, scalable and cost-effective monitoring systems that can be operated from mobile platforms in the Adriatic Sea. Their applications include monitoring of: coastal areas shifting water dynamics due to changing seasons; monitoring of leakage from abandoned or decommissioned wells/boreholes/sealines, reservoirs, shallow gas accumulations.
Data and information collected with innovative and autonomous technology is essential to reduce uncertainties of offshore multi-hazards and can help strengthening the integrated, interoperable sharing of marine environmental information with decision makers, civil protection and the public.