Methane is a potent greenhouse gas and its atmospheric concentration has more than doubled since industrialisation. While anthropogenic sources to the atmospheric methane budget are comparably well constrained, it is still a major challenge for science to understand and quantify the contribution of natural sources. One reason for this knowledge gap is that the spatial distribution of methane accumulations within the marine and terrestrial realms is not fully resolved. Furthermore, geological and biological perspectives of spatial and temporal controls on methane cycling (i.e. gas hydrate accumulations, methane production, migration, consumption and emission) need further investigation for reliable estimations of the methane flux from individual sources to the atmosphere.

The topics of the session will include, but are not restricted to:
- Methane formation (bio- and geo-processes).
- Subsurface fluid flow, methane/hydrocarbon transport mechanisms and emissions.
- Seep-related geological structures: mud volcanoes and pock marks.
- Geophysical manifestation of shallow gas, thermal gradients and seepage dynamics.
- The potential of methane hydrates as future energy resource
- Scientific & engineering advances in gas hydrate exploitation
- The sub-seabed storage of CO2 as solid gas hydrates
- The potential danger of melting gas hydrates on accelerating climate change and ocean acidification
- The role of methane hydrates in benthic ecosystems such as chemosynthetic cold-seep habitats
- Methane in present-day and palaeoenvironments including (bio)geo-archives and reconstructions.
- Geo- and bio-monitoring of seepage systems.
- Methane/hydrocarbons sequestration and ecosystem response.
- Seep-associated microbial communities and interactions.
- Methane-derived carbonates and microbe-mineral interractions.
- Methane related element cycling and coupling.
- Quantification of methane fluxes.
- Reduction of methane emissions and methane as renewable energy.
- Instrument development for measurements of methane and other greenhouse gases.


The session will highlight the significance of (geo)physical, geological, (geo)chemical and (micro)biological controls on methane release in ocean, permafrost, wetlands and lake environments. We will also discuss recent advances on gas hydrate properties & occurrences in marine sediments and new developments in hydrate reservoir utilisation. We aim at providing an interdisciplinary platform for scientists from the fields of geology, biogeochemistry, (geo)physics, modelling, chemistry, microbiology as well as ecology, in order to evaluate our current knowledge of marine and terrestrial methane turnover, interactions between element cycles and ecosystems, environmental controls and mechanisms. A further intention is to create synergies between marine and terrestrial sciences for a multifaceted view on methane cycling. This session is also an invitation to scientists from the wider field of environmental geo- and/or bio-engineering dealing with natural methane emissions as an alternative energy source. We also welcome specialists designing instruments for autonomous and continuous measurements of methane and other greenhouse gases.