CORPUS CHRISTI, Texas – Methane hydrates are believed to be a significant, globally-available energy resource, predicted to be two to three times more abundant than petroleum reserves. If these deposits of methane hydrates could be efficiently mined, they could become a large source of energy worldwide.
This summer, a team of professors and students from the Island University studied methane hydrates off the coast of New Zealand.
Dr. Richard Coffin, Chair of the Department of Physical and Environmental Sciences at Texas A&M University-Corpus Christi, co-led a geochemistry team aboard the Research Vessel Tangaroa with Dr. Paula Rose, a University Research Scientist.
Graduate students Josette Delgado, marine biology; Melanie Gingras, coastal and marine systems science; and undergraduate student Branden Canete, chemistry, also participated in the research cruise.
The multi-million dollar, three-week expedition sought to characterize gas source and composition at key locations on the Hikurangi Margin, where the Pacific Plate is being pushed under the Australian Plate. Compression between the plates results in an over-pressurized system and an active vertical fluid and gas flux to the shallow sediment where gas hydrates can form.
“This is some of the most exciting research that I have worked on and I believe that the data collected this summer and over the coming months will make a major contribution to quantifying of methane hydrate loadings off New Zealand and globally,” said Coffin, who has led and participated in global expeditions on basic research and energy exploration for more than 15 years.
Gas hydrates occur in shallow sediments worldwide but their abundance is not well-characterized. In addition to being a possible future energy source, methane hydrates are also being studied to better understand Earth’s carbon budgets, their contribution to climate change, and their potential impact on industrial platform stability.
Methane hydrates are often called “fiery ice,” or “fire ice”; this substance resembles an ice crystal, and starts burning when an open flame is brought near to it, thus the nickname. It is a cage-like structure of ice where methane – the chief ingredient of natural gas – is trapped inside.
During the expedition, geophysicists from the University of Auckland, New Zealand’s National Institute for Water and Atmospheric Research and Geologic Nuclear Survey, collected more than 750 km of seismic data and more than 2,000 km2 of acoustic data showing active gas migration and free gas below the sediment surface. These data were used to focus the geochemistry team’s coring effort.
While at sea, the geochemistry team collected 66 sediment cores and more than 6,000 samples for geochemical analysis. Hundreds of samples were analyzed onboard. The rest will be analyzed at Texas A&M-Corpus Christi’s Isotope Core Laboratory, the US Naval Research Laboratory, and at the University of Hawaii. Subsequently, the data will be used to assess gas flux and hydrate abundance.