The project goal was to develop new methodologies to characterize the physical properties of methane hydrate and hydrate sediment systems.
Westport Technology Center International - Houston, TX
University of Houston - Houston, TX
Project researchers created a pressure cell for measuring acoustic velocity and resistivity on hydrate-sediment cores. They utilized the measurements for input to an existing reservoir model for evaluating possible offshore hydrate accumulations. The organization of an industry-led Advisory Board and the development of a Research Management Plan have been completed. The development of a handbook for transporting, preserving, and storing hydrate core samples brought from the field to the laboratory was completed and distributed for review by industry and researchers.
Other accomplishments include having characterized the bulk system properties for various porous media containing gas, water, and hydrates. Four media (two synthetic quartz-based systems, a Berea sandstone core, and a simulated unconsolidated Gulf of Mexico sediment) were selected, and measurements of a variety of bulk system properties for each system were completed. Prior to the formation of hydrates within these cores, baseline geomechanical, electrical, and acoustic properties of the hydrate-free cores were measured and recorded as baseline information.
Benefits of this research
This project helped enhance the understanding of the properties of methane hydrate as it forms and dissociates in natural sediments. This may help aid researchers in developing the ability to effectively locate and quantify hydrate occurrence in nature, as well as in attempting to clarify proper handling methodologies for methane hydrate-containing cores recovered during research activities.
The characteristics of hydrates are generally understood in the absence of natural sediments, but much remains to be learned regarding the behavior of hydrates under actual seafloor conditions. The models that are currently available to describe that behavior are not adequate, due either to a lack of sufficient data or to insufficient confidence in the validity of mechanisms defining hydrate formation and dissolution in sediments. This project is focused on providing those data.
The proposed project entails an industry effort to collect the necessary field data to create standard methods of data acquisition and then develop or modify a reservoir model to utilize the information. The project performer has a historical record of creating similar services for the petroleum industry.
A compilation of current best practices, developed through discussions with industry, academia, national laboratories, and government agencies, was completed and is available upon request to DOE - NETL. Experiments have been carried out to form and dissociate methane hydrates within sediment samples (defined above) of varying characteristics. These activities include measuring temperature and pressure requirements for methane hydrate formation, as well as measuring characteristics in the samples, including resistivity and seismic velocities. These data were used to evaluate characteristics of the hydrate-bearing samples, including porosity, permeability, and gas, water, and hydrate saturations. In addition, the samples were CT-scanned to provide 3-D visualization of the hydrate formation and dissociation process. These experiments were performed in Westport's pressure cells, as well as in the core holder built to hold the samples described above.
The following conclusions are offered by the performer as result of work performed under this effort:
All research under this award is complete. The project final report and other available deliverables are listed under the "Additional Information" section below.
This project was awarded funding under a DOE solicitation conducted in accordance with the Methane Hydrate Research and Development Act of 2000.
Final Report [PDF-9.04MB]
Users Manual for Natural Gas Hydrate Core Handling Procedures. CDROM