Abstract: Methods and systems for determining whether conditions exist for presence of clathrates are disclosed. One method includes determining a thickness of a clathrate stability zone based, at least in part, on a depth at which a temperature reaches a three-phase equilibrium temperature of the clathrates. The method also includes calculating a temperature and a three-phase equilibrium temperature for a range of depths in the clathrate stability zone, and determining a minimum pore size at each of the depths in the range of depths, the minimum pore size permitting a predetermined saturation level of clathrates and based at least in part on the temperature and three-phase equilibrium temperature. The method further includes converting the minimum pore size at each of the depths to a minimum porosity.

Abstract: Methods and systems for determining a presence and saturation of clathrates are provided. One method includes identifying a potential zone of clathrates based on observed seismic data, the observed seismic data including an observed signal amplitude at the potential zone of clathrates, and assigning subsurface sediment types within and around the potential zone of clathrates. The method includes creating one or more lithologic type logs based on the interpreted subsurface sediment types, and creating from each of the one or more lithologic type logs a plurality of synthetic logs including compressional velocity at a plurality of possible clathrate saturation levels. The method includes matching expected signals from one of the plurality of synthetic logs to the observed signals in the observed seismic data to determine a best-fit match synthetic log to the observed seismic data, thereby determining a clathrate saturation level from among the plurality of possible clathrate saturation levels.

Abstract: Methods and systems for determining a maximum pore size in a distribution of varying-sized spherical particles are disclosed. One method includes distributing a plurality of particles within a volume, and, at each point unoccupied by a particle, inscribing a sphere and determining a size of the sphere. The method further includes determining a maximum size of a sphere from among the spheres inscribed at each unoccupied point, thereby locating a maximum pore size location within the volume.

Abstract: Methods and systems for determining whether conditions exist for presence of clathrates are disclosed. One method includes determining a thickness of a clathrate stability zone based, at least in part, on a depth at which a temperature reaches a three-phase equilibrium temperature of the clathrates. The method also includes calculating a temperature and a three-phase equilibrium temperature for a range of depths in the clathrate stability zone, and determining a minimum pore size at each of the depths in the range of depths, the minimum pore size permitting a predetermined saturation level of clathrates and based at least in part on the temperature and three-phase equilibrium temperature. The method further includes converting the minimum pore size at each of the depths to a minimum porosity.