Hydrates From Ice (HyFI)

This webpage presents motivations, measurement details, data and published interpretations from the HyFI system.  The site map provided on the left of the page indicates the page being viewed with a small star, and can be used to navigate the site.  For readers interested in a general overview of our methane hydrate thermal property studies, a USGS Fact sheet is available for download.  For readers interested in more detailed interpretations and published data, the measurements are summarized below with direct links to the systems studied to date. Hydrate pressure vessel in a temperature-controlled bath. Bath is 30 cm across and 60 cm deep (Click picture for larger image).

HyFI Facility at the USGS Science Center in Woods Hole, MA. Experimental apparatus is housed in the fume hood (right), and controlled with data acquisition hardware on the shelves to the left (Click picture for larger image).

What is HyFI?

The HyFI test system is designed for measuring properties of sediments and pure-phase materials, with a particular focus on gas hydrates. The term "Hydrates From Ice" refers to a technique in which hydrate is formed by slowly warming granular ice in a pressurized atmosphere of the hydrate former (methane, for instance). This methodology was developed at the USGS (Menlo Park) by Dr. Stephen Kirby and Laura Stern [Stern et al., 1996; 1998].

During an experiment, a pressure vessel containing hydrate rests in a temperature controlled bath capable of maintaining stable temperatures from -25°C up through the hydrate stability temperature (generally less than room temperature). The bath itself is held in a chest freezer to insulate it from room air fluctuations. The chest freezer and bath controller are housed in a fume hood. The hood provides a measure of safety in case of gas leaks during experiments with hydrocarbon gases, and allows us to work with volatile hydrate formers such as tetrahydrofuran (THF).

Measurements made:

HyFI has been used to measure thermal properties, defined succinctly by Briaud and Chaouch [1997]:

Thermal conductivity, λ: if λ is high, heat travels easily through the material.

Thermal diffusivity, κ: if κ is high, it takes little time for the temperature to rise in the material.

Specific heat, c_p: if c_p is high, it takes a lot of heat to raise the temperature of the material.

The U.S. Geological Survey (USGS) is investigating gas hydrate thermal properties in support of efforts by the USGS and others to obtain methane from gas hydrates as an energy resource, mitigate the geohazard potential of gas hydrates, and understand the role hydrate-derived methane plays in global climate change. Our published data are available for download via links at the bottom of each measurement result page, just below the journal citation.

Pure-phase systems

Mixed-Phase Systems