Gas hydrates offer a vast, untapped source of energy, a key element in the global carbon balance and past global warming events, and the number one problem for hydrocarbon transmission in deepwater oil and gas production. As described in this document, the Rice University Center for Gas Hydrates Research offers an interdisciplinary team of scientists and engineers focused on gas hydrate issues in each of these areas.
Burning Gas Hydrate

A burning gas hydrate. The heat from the flame melts the hydrate thus releasing more methane to fuel the flame. Notice the water dripping from the person’s hands
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What are Gas Hydrates?

Gas hydrates are crystalline solids composed of gas molecules trapped inside a rigid lattice of water molecules. These compounds are stable at conditions of relatively low temperature and relatively high pressure. Gas hydrates that are primarily composed of methane (the main component of natural gas) and water occur naturally in Arctic permafrost at depths greater than 200 meters, and they also form in marine sediments at ocean floor depths greater than 500 meters where temperatures hover near freezing and the weight of the water produces high pressures.

Why is Gas Hydrate Research so important?

Naturally occurring gas hydrates represent a major source of untapped energy. It is estimated that more energy resides in gas hydrates than in all of the energy available in existing gas, oil and coal resources. Gas trapped within or below the hydrates structure has the potential to be extracted and utilized just as conventional natural gas resources are today across the globe. The challenge is to develop environmentally safe and economic procedures by which to locate and extract the largest gas accumulations trapped by hydrate structures.
Gas hydrates research may also be a key to gaining greater understanding of carbon cycles and an important element in climate change study. Studies of geologic record indicate several past intervals of deep ocean warming, such as the Paleocene/Eocene thermal maximum 55 million years ago, when immense quantities of carbon suddenly entered the ocean and atmosphere, possibly deriving from a disruption of gas hydrates. Further study is needed to determine the conditions and extent to which future warming of the oceans could stimulate the escape of massive amounts of methane – a potent greenhouse gas — should hydrate structures be disturbed in the process.

Gas hydrates can plug flow lines in offshore energy production creating an economic and safety problem. Oil and gas companies presently spend more than half a billion dollars annually on chemical inhibitors to prevent gas hydrate plugging. Formation of gas hydrate plugs also plague further refining of natural gas products. Rice has long been recognized for the quality phase behavior and calorimetric data used by the gas industry to prevent blockages. Research is needed to understand the mechanism and kinetics of hydrate formation and decomposition and the effects of chemical inhibitors.

Greater understanding is needed of the science of hydrates resource development as well as its environmental implications. The scientific community has documented the fundamental characteristics of gas hydrates systems, but to gain the knowledge needed to tap this energy source in a commercially viable and environmentally sound manner and to understand the global carbon cycles, these observations must be elaborated, including the creation of predictive models that indicate more accurately and clearly how gas hydrate systems accumulate, dissociate and operate.


Gas Hydrates and Energy Supply

Gas hydrates have been identified under Arctic regions and continental margins in many locations throughout the world, including the United States. Beneath the Alaskan North Slope (ANS) and within the U.S. Exclusive Economic Zone (EEZ) offshore gas hydrates probably contain between 110,000-670,000 trillion cubic feet (TCF) of methane.

Several nations, most notably Canada, Japan, India and the United States, are engaged in active gas hydrates research and evaluation programs. A study released in September 2002 by researchers at the University of Victoria found that a huge portion of Canada’s energy reserve potential lies in onshore and offshore gas hydrates. Resource-poor Japan has become a global leader in gas hydrates exploration and in March 2002, Japan National Oil Corporation (JNOC) announced that JNOC, along with its international partners, succeeded in production of gas hydrate – the first time that gas hydrate was recovered through its underground dissociation into methane gas.


Worldwide locations where gas hydrate has been sampled or inferred from seismic records.
These areas cover both occurrences in continental margins and permafrost regions.

U.S. companies, such as Anadarko Petroleum Corporation, BP Exploration (Alaska), Inc., and ChevronTexaco are all conducting gas hydrates research and exploration. While most gas hydrate probably occurs dispersed in the pore space of sediment in low concentrations, significant amounts of gas hydrate have been discovered in some focused areas such as the crest of Hydrate Ridge off the coast of Oregon. These “sweet” spots could become a significant energy resource for the United States.

Burning Gas Hydrate
Worldwide distribution of organic carbon. Methane hydrates contain more organic carbon than all known fossil fuels by a factor of 2.
The DOE and United States Geological Survey (USGS) partnered with the Geological Survey of Canada, Japan National Oil Corporation, BP-Chevron-Burlington Joint Venture Group and others to drill appraisal and production test wells in the Mackenzie Delta of the Canadian Arctic in 2002. The results of this research will be disclosed in December 2003. The DOE recently partnered with Anadarko, Noble Engineering and Development and Maurer Technology to conduct a test program near Deadhorse, Alaska. This type of committed research and exploration is key to unlocking this potential source of energy and doing so in a way that is environmentally acceptable and commercially viable.

Gas hydrates are usually found in low concentrations in natural sediments. Economic extraction requires finding locations where large, concentrated accumulations of gas hydrate/free gas occur. To identify with accuracy and consistency large, concentrated accumulations will require a better understanding of the mechanisms governing the migration and accumulation of gas hydrates and associated free gas. The technology for locating and developing gas hydrates is in its infancy compared to the knowledge available for oil and gas. Rice University researchers believe cross-disciplinary research is needed to enhance understanding of the complex set of scientific issues involved. Much of the existing work has been conducted within individual disciplines such as geology, oceanography, engineering and biology. Modeling that would take knowledge from each of these fields into account is necessary to build a concrete basis for understanding these complicated processes.

Environmental Implications of Gas Hydrates Research


Current scientific literature has emphasized that gas hydrates probably play a major though unconstrained role in the global carbon cycle and climate change models. The large amount of carbon stored in gas hydrates is likely 10 to 20 times the mass of carbon in the atmosphere. This means that a relatively small release of methane from gas hydrate systems could have significant impact. Current carbon cycle models, however, neglect gas hydrates and possible methane releases, and it is not well understood why, how, where, and when gas hydrates should be incorporated into the global carbon cycle. In order to develop this concept and account for seafloor methane release from natural disturbances such as rising ocean temperature or from methane production, a cross-disciplinary approach is needed that includes study of inputs and outputs of methane to and from the ocean and atmosphere and how these fluxes can be perturbed.

Burning Gas Hydrate
Worldwide distribution of organic carbon. Methane hydrates contain more organic carbon than all known fossil fuels by a factor of 2.
Rice researchers have conducted significant initial research into the topic of gas hydrates and climate change. In a recent article in Earth and Planetary Science letters, Rice professor Gerald Dickens presents the first basic global carbon cycle that includes gas hydrates. According to this model, significant amounts of methane have been released from gas hydrates during several past intervals of abrupt (< 100kyr) environmental change when ocean bottom water warms.

The stability of the seafloor can be affected by gas hydrates in underlying sediment. In addition to the methane release from changing environmental conditions, the safety of offshore drilling platforms is a major concern in the commercial production of energy from gas hydrates. The impact drilling for gas hydrates has on seafloor stability is currently unknown, and further research is needed to assess the safety of gas hydrate production. ChevronTexaco recently partnered with the DOE to address the issues related to gas hydrate production and seafloor stability. Rice believes that committed, cross-disciplinary research is necessary to fully understand and model the interactions of the gas hydrate deposits with the stability of the structures that rest upon them.
Role of the Private and Public Sectors

Current scientific literature has emphasized that gas hydrates probably play a major though unconstrained role in the global carbon cycle and climate change models. The large amount of carbon stored in gas hydrates is likely 10 to 20 times the mass of carbon in the atmosphere. This means that a relatively small release of methane from gas hydrate systems could have significant impact. Current carbon cycle models, however, neglect gas hydrates and possible methane releases, and it is not well understood why, how, where, and when gas hydrates should be incorporated into the global carbon cycle. In order to develop this concept and account for seafloor methane release from natural disturbances such as rising ocean temperature or from methane production, a cross-disciplinary approach is needed that includes study of inputs and outputs of methane to and from the ocean and atmosphere and how these fluxes can be perturbed.


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