Oceanic Gas Hydrate Research and Activities Review

2. As exploration and development activities have moved into deeper water, gas hydrates are an increasingly important concern. This presentation gives an overview of gas hydrates including what they are, why there is so much interest in them, and ends with what areas are of interest to MMS, both in the short term and long term. In your package, you received a document titled “Oceanic Gas Hydrate Research and Activities Review.” This is a living document and any comments you have would be greatly appreciated. I can give you my business card after this presentation.As exploration and development activities have moved into deeper water, gas hydrates are an increasingly important concern. This presentation gives an overview of gas hydrates including what they are, why there is so much interest in them, and ends with what areas are of interest to MMS, both in the short term and long term. In your package, you received a document titled “Oceanic Gas Hydrate Research and Activities Review.” This is a living document and any comments you have would be greatly appreciated. I can give you my business card after this presentation.

3. Gas hydrates are a crystalline or ice-like structure that forms a cage around a molecule of gas, as you can see here. The water molecules are bonded to form the structure and, in this case, a methane molecule is trapped inside. The gas that is trapped can be methane, carbon dioxide, hydrogen sulfide and some smaller hydrocarbon molecules like ethane, butane, and propane. Gas hydrates are a crystalline or ice-like structure that forms a cage around a molecule of gas, as you can see here. The water molecules are bonded to form the structure and, in this case, a methane molecule is trapped inside. The gas that is trapped can be methane, carbon dioxide, hydrogen sulfide and some smaller hydrocarbon molecules like ethane, butane, and propane.

4. The cage can take several forms as seen here. All three have been observed in nature, but they can also be synthesized in the laboratory. The interest in methane hydrates as a potential resource results from the trapping capability of the hydrate structure. Essentially, hydrates concentrate gas by a ratio of 1:160. What this means, is that in one cubic foot of hydrate, about 160 cubic feet of gas is trapped. This would be 160 cubic feet at standard temperature and pressure.The cage can take several forms as seen here. All three have been observed in nature, but they can also be synthesized in the laboratory. The interest in methane hydrates as a potential resource results from the trapping capability of the hydrate structure. Essentially, hydrates concentrate gas by a ratio of 1:160. What this means, is that in one cubic foot of hydrate, about 160 cubic feet of gas is trapped. This would be 160 cubic feet at standard temperature and pressure.

5. For hydrates to from, several ingredients are necessary. Of course, you need water to form the cage and gas to fill the cage. The reason that hydrates are of interest in deep water is that they also need high pressures and low temperatures. In addition, a nucleation site is required. The nucleation site would be a surface such as a grain of clay or a pipeline or a piece of platform. This is why you don’t find have hydrates floating around in seawater. For hydrates to from, several ingredients are necessary. Of course, you need water to form the cage and gas to fill the cage. The reason that hydrates are of interest in deep water is that they also need high pressures and low temperatures. In addition, a nucleation site is required. The nucleation site would be a surface such as a grain of clay or a pipeline or a piece of platform. This is why you don’t find have hydrates floating around in seawater.

6. These are some examples of hydrates that have been recovered. In the top picture, you can see the white banding, which is the hydrate. The lower left picture is a nodule of hydrate and on the right is a hydrate recovered from the Gulf of Mexico, which is coated with oil. As you can see, hydrates from within the sediments and you would not expect to find huge blocks of hydrate in the sediments, there isn’t room for them to form. You do see outcrops in the Gulf, and I will discuss this further later in the presentation.These are some examples of hydrates that have been recovered. In the top picture, you can see the white banding, which is the hydrate. The lower left picture is a nodule of hydrate and on the right is a hydrate recovered from the Gulf of Mexico, which is coated with oil. As you can see, hydrates from within the sediments and you would not expect to find huge blocks of hydrate in the sediments, there isn’t room for them to form. You do see outcrops in the Gulf, and I will discuss this further later in the presentation.

7. As I said, you need the right pressure and temperature conditions for hydrates to form. On the left is a plot of temperature vs. depth, which can be treated as pressure. That is to say that increasing depth also means increasing pressure. If the depth and temperature of a location plot in the shaded area, then the conditions are right for hydrates to form. If the temperature and pressure plot in the white area, then methane gas is stable. Also, if you increase the pressure, then you increase the temperature at which hydrates can form. The upper depth is about 300m, meaning you would not expect to find hydrates in areas that are shallower than about 300 m. Again, this is the reason for the increased interest in hydrates as oil and gas activities move into deeper water. The plot on the right basically shows the same thing with temperature plotted against depth. The main point here is that as you go deeper below the seafloor, the temperature increases due to the heat from deep within the earth. At some point the temperature is too high for hydrates, and the cage breaks down leaving free gas. The result is that below the seafloor, there is a zone or band where the conditions are right for hydrate formation. As I said, you need the right pressure and temperature conditions for hydrates to form. On the left is a plot of temperature vs. depth, which can be treated as pressure. That is to say that increasing depth also means increasing pressure. If the depth and temperature of a location plot in the shaded area, then the conditions are right for hydrates to form. If the temperature and pressure plot in the white area, then methane gas is stable. Also, if you increase the pressure, then you increase the temperature at which hydrates can form. The upper depth is about 300m, meaning you would not expect to find hydrates in areas that are shallower than about 300 m. Again, this is the reason for the increased interest in hydrates as oil and gas activities move into deeper water. The plot on the right basically shows the same thing with temperature plotted against depth. The main point here is that as you go deeper below the seafloor, the temperature increases due to the heat from deep within the earth. At some point the temperature is too high for hydrates, and the cage breaks down leaving free gas. The result is that below the seafloor, there is a zone or band where the conditions are right for hydrate formation.

8. The lower boundary where hydrates can form also shows up in seismic data as you can see here. The boundary where hydrates cannot form and there is actually gas in the sediments creates a demarkation called a bottom simulating reflector. As you can clearly see here, there is al ine that follows the bottom but is at some depth below the bottom. This line also cuts across the geological layers, indicating that is not due to a change in geology. The BSR is attributed to the change from the ice-like solid to gas in water.The lower boundary where hydrates can form also shows up in seismic data as you can see here. The boundary where hydrates cannot form and there is actually gas in the sediments creates a demarkation called a bottom simulating reflector. As you can clearly see here, there is al ine that follows the bottom but is at some depth below the bottom. This line also cuts across the geological layers, indicating that is not due to a change in geology. The BSR is attributed to the change from the ice-like solid to gas in water.

9. There are several reasons for the interest in gas hydrates and I will be explaining each in greater detail. The safety issues include plugging of flowlines and geohazards. Methane hydrate is considered a potentials reasource. And of environmental concern, sensitive biological communities exist on outcrops. Hydrates may also contribute to global warming.There are several reasons for the interest in gas hydrates and I will be explaining each in greater detail. The safety issues include plugging of flowlines and geohazards. Methane hydrate is considered a potentials reasource. And of environmental concern, sensitive biological communities exist on outcrops. Hydrates may also contribute to global warming.

10. Safety is a major concern for oil and gas activities. Structures contain many pipelines, flowlines, and parts that can trap gas and become encrusted with hydrates. Also, since hydrates occur naturally in sediments, the positioning of platforms, anchors, and pipelins can be affected.Safety is a major concern for oil and gas activities. Structures contain many pipelines, flowlines, and parts that can trap gas and become encrusted with hydrates. Also, since hydrates occur naturally in sediments, the positioning of platforms, anchors, and pipelins can be affected.

11. Hydrates in pipelines can either completely plug the line, or from ice balls that can act like projectiles. Platforms can have many lines that could become plugged. Industry has been researching different methods to prevent the formation of hydrates for 25 years. The present methods include using large volumes of chemicals such as methanol and glycol. Recent research has been exploring the use of chemical inhibitors that are more expensive but can be used in much smaller volumes.Hydrates in pipelines can either completely plug the line, or from ice balls that can act like projectiles. Platforms can have many lines that could become plugged. Industry has been researching different methods to prevent the formation of hydrates for 25 years. The present methods include using large volumes of chemicals such as methanol and glycol. Recent research has been exploring the use of chemical inhibitors that are more expensive but can be used in much smaller volumes.

12. Hydrates in the seafloor sediment can also be a potential source of problems. Heat from production wells could cause hydrate dissociation and possible collapse of the casing. Also, heat from buried pipelines could cause hydrate dissociation. Also, hydrates can also form on the exterior of equipment, causing it not to function properly.Hydrates in the seafloor sediment can also be a potential source of problems. Heat from production wells could cause hydrate dissociation and possible collapse of the casing. Also, heat from buried pipelines could cause hydrate dissociation. Also, hydrates can also form on the exterior of equipment, causing it not to function properly.

13. The Gulf of Mexico is unique in that it is one of only a few areas where hydrates form outcrops at the seafloor. These outcrops have been studied by MMS contractors using submarines such as this. The hydrate outcrops are generally about the size of a conference table. Interestingly, there chunks can break off and float away. One of our contractors has revisited a site only to find a hole where there once was a hydrate mound. Research is presently underway a the Center for Marine Resources and Environmental Technology to monitor hydrates and possibly gain a better understanding on how ephemeral hydrates can be.The Gulf of Mexico is unique in that it is one of only a few areas where hydrates form outcrops at the seafloor. These outcrops have been studied by MMS contractors using submarines such as this. The hydrate outcrops are generally about the size of a conference table. Interestingly, there chunks can break off and float away. One of our contractors has revisited a site only to find a hole where there once was a hydrate mound. Research is presently underway a the Center for Marine Resources and Environmental Technology to monitor hydrates and possibly gain a better understanding on how ephemeral hydrates can be.

14. One scenario for the outcrops in the Gulf of Mexico is believed to be a result of the dynamic geology in the Gulf. Essentially, the migrating salt causes faults fissures in the overlying sediments. The resultant structure also enables the trapping of hydrocarbons at depth. The lighter hydrocarbons migrate up the fissures to the surface and form hydrate outcrops at the surface. We now have a proposal from Dr. Harry Roberts to test this hypothesis in the Gulf using data from MMS about the surface signature and the underlying geology. This information will be used by the Leasing and Environment section to better interpret surface seismic data submitted with applications and used to apply mitigations requiring avoidance of the surface outcrops and associated sensitive communities. One scenario for the outcrops in the Gulf of Mexico is believed to be a result of the dynamic geology in the Gulf. Essentially, the migrating salt causes faults fissures in the overlying sediments. The resultant structure also enables the trapping of hydrocarbons at depth. The lighter hydrocarbons migrate up the fissures to the surface and form hydrate outcrops at the surface. We now have a proposal from Dr. Harry Roberts to test this hypothesis in the Gulf using data from MMS about the surface signature and the underlying geology. This information will be used by the Leasing and Environment section to better interpret surface seismic data submitted with applications and used to apply mitigations requiring avoidance of the surface outcrops and associated sensitive communities.

15. This map shows locations of known or suspected gas hydrate outcrops on the slope in the Gulf of Mexico. Oil discoveries and seep communities are also included.This map shows locations of known or suspected gas hydrate outcrops on the slope in the Gulf of Mexico. Oil discoveries and seep communities are also included.

16. Moving on to methane hydrates as a resource. This diagram was prepared by the USGS and represents the estimated reservoirs of carbon on the earth’s surface excluding dispersed carbon in rocks and sediments. The large yellow section is the estimates of carbon locked up in hydrates which is double the amount of carbon in fossil fuels. The other compartments include the land, the ocean, and the atmosphere.Moving on to methane hydrates as a resource. This diagram was prepared by the USGS and represents the estimated reservoirs of carbon on the earth’s surface excluding dispersed carbon in rocks and sediments. The large yellow section is the estimates of carbon locked up in hydrates which is double the amount of carbon in fossil fuels. The other compartments include the land, the ocean, and the atmosphere.

17. Gas hydrates are distributed worldwide. Here the red and pink are offshore sample sites. The yellow indicates inferred hydrates from seismic data as I described earlier. The orange squares are onshore sites where hydrates form in permafrost.Gas hydrates are distributed worldwide. Here the red and pink are offshore sample sites. The yellow indicates inferred hydrates from seismic data as I described earlier. The orange squares are onshore sites where hydrates form in permafrost.

18. The USGS has estimated the trillion cubic feet of methane trapped in hydrates. The Alaska Offshore Province has the largest percentage of the resource and the Gulf of Mexico has the least. The USGS has estimated the trillion cubic feet of methane trapped in hydrates. The Alaska Offshore Province has the largest percentage of the resource and the Gulf of Mexico has the least.

19. The Blake Ridge has the offshore area that has been studied the most extensively. Estimated thickness of hydrates in sediment are as much as 60 meters. The scale represents 25 miles. Whether the hydrate is extractable is still unknown.The Blake Ridge has the offshore area that has been studied the most extensively. Estimated thickness of hydrates in sediment are as much as 60 meters. The scale represents 25 miles. Whether the hydrate is extractable is still unknown.

20. The methods of extraction that have been proposed include heat, which would result in the breakdown of the cage and release of the gas. Carbon dioxide can be injected and displace the methane. The pressure can be reduced, again breaking down the cage and releasing the gas. Direct removal is the most destructive and would be similar to coal mining. Also, inhibitors such as methanol can be injected, again destroying the cage structure.The methods of extraction that have been proposed include heat, which would result in the breakdown of the cage and release of the gas. Carbon dioxide can be injected and displace the methane. The pressure can be reduced, again breaking down the cage and releasing the gas. Direct removal is the most destructive and would be similar to coal mining. Also, inhibitors such as methanol can be injected, again destroying the cage structure.

21. I’ve already discussed alittle bit about the outcrops of gas hydrates in the Gulf of Mexico and the association of chemosynthetic communities with these outcrops.I’ve already discussed alittle bit about the outcrops of gas hydrates in the Gulf of Mexico and the association of chemosynthetic communities with these outcrops.

22. Here are some examples of the life that is associated with the hydrates. MMS has funded two large projects to study these unique communities. On the left are ice worms colonizing a methane hydrate outcrop. The worm is about 2” long and are affectionately known as ice worms. On the right are tube worms that are also associated with hydrates. They form large bushes with some of the worms estimated to be 100-200 years old. In addition, other creatures such as the spider crab reside in the bush.Here are some examples of the life that is associated with the hydrates. MMS has funded two large projects to study these unique communities. On the left are ice worms colonizing a methane hydrate outcrop. The worm is about 2” long and are affectionately known as ice worms. On the right are tube worms that are also associated with hydrates. They form large bushes with some of the worms estimated to be 100-200 years old. In addition, other creatures such as the spider crab reside in the bush.

23. In addition, hydrates may play a role in global warming. Methane gas is a major greenhouse gas. Dissociation of mthane hydrates could result in an increase in methane in the atmosphere. In contrast, the exploitation of methane hydrates and an increased use of methane as an energy source could reduce the amount of carbon dioxide emitted into the atmosphere.In addition, hydrates may play a role in global warming. Methane gas is a major greenhouse gas. Dissociation of mthane hydrates could result in an increase in methane in the atmosphere. In contrast, the exploitation of methane hydrates and an increased use of methane as an energy source could reduce the amount of carbon dioxide emitted into the atmosphere.

24. Presently, Congress is working on two bills, S. 330 and H.R. 1753 to fund the Methane Hydrate Research and Development Act of 1999 to research, indentify, assess, explore, and develop methane hydrates as a resource. The bills authorize the expenditure of approximately 42 million dollars over the next five years. These are not an appropriations bills. The lead agency would be the Department of Energy with DOI and DOD in consultation. The bills or a combined bill are expected to pass this year.Presently, Congress is working on two bills, S. 330 and H.R. 1753 to fund the Methane Hydrate Research and Development Act of 1999 to research, indentify, assess, explore, and develop methane hydrates as a resource. The bills authorize the expenditure of approximately 42 million dollars over the next five years. These are not an appropriations bills. The lead agency would be the Department of Energy with DOI and DOD in consultation. The bills or a combined bill are expected to pass this year.

25. On the international front, other countries are investing in programs to recover methane hydrates. In particular, Russia has extracted methane from a field in Siberia. India and Japan are actively pursuing the recovery of offshore methane hydrates. Experiments are going on in Canada to extract hydrates from permafrost. There is also interest in the United Kingdom, Brazil, and Norway.On the international front, other countries are investing in programs to recover methane hydrates. In particular, Russia has extracted methane from a field in Siberia. India and Japan are actively pursuing the recovery of offshore methane hydrates. Experiments are going on in Canada to extract hydrates from permafrost. There is also interest in the United Kingdom, Brazil, and Norway.

26. Within the United States, the Department of Energy has spent about 8 million during the late 80’s and early 90’s and is expecting the funding for a large program that I described earlier. The Geologic Survey has been funding research into hydrates for over 25 years and is responsible for the present estimates of the resource. The Naval Research Laboratory is interested in the effects of hydrates on the acoustic properties of sediments. The National Science Foundation is funding basic research at thelevel of 0.5 to 1 million dollars per year. Within the United States, the Department of Energy has spent about 8 million during the late 80’s and early 90’s and is expecting the funding for a large program that I described earlier. The Geologic Survey has been funding research into hydrates for over 25 years and is responsible for the present estimates of the resource. The Naval Research Laboratory is interested in the effects of hydrates on the acoustic properties of sediments. The National Science Foundation is funding basic research at thelevel of 0.5 to 1 million dollars per year.

27. Within MMS, hydrate research has been funded on a small scale for about 10-15 years. The technology and assessment research program has funded four small projects including a book on hydrates with emphasis on flowline issues. The environmental studies program has funded two projects to study chemosynthetic communities. The Center for Marine Resources and Environmental Technology is studying the dissociation of hydrates at a site in the Gulf of Mexico. The Gulf of Mexico Resource Evaluation section has reprocessed 3-D seismic data to look at surface anomalies that are attributed to sea floor composition that has a higher density than the surrounding soft sediments. These anomalies may be exposed hydrate or carbonate. I’ll discuss this more later. MMS employees are also members of several committees or are involved in several consortiums. Within MMS, hydrate research has been funded on a small scale for about 10-15 years. The technology and assessment research program has funded four small projects including a book on hydrates with emphasis on flowline issues. The environmental studies program has funded two projects to study chemosynthetic communities. The Center for Marine Resources and Environmental Technology is studying the dissociation of hydrates at a site in the Gulf of Mexico. The Gulf of Mexico Resource Evaluation section has reprocessed 3-D seismic data to look at surface anomalies that are attributed to sea floor composition that has a higher density than the surrounding soft sediments. These anomalies may be exposed hydrate or carbonate. I’ll discuss this more later. MMS employees are also members of several committees or are involved in several consortiums.

28. As I just mentioned, the Gulf of Mexico Resource Evaluation section has been reprocessing 3-D seismic data to look at surface anomalies. This is an image of the Gulf of Mexico sea floor reconstructed from the data. Please focus on the upper part of the section where there is a topographical high.As I just mentioned, the Gulf of Mexico Resource Evaluation section has been reprocessing 3-D seismic data to look at surface anomalies. This is an image of the Gulf of Mexico sea floor reconstructed from the data. Please focus on the upper part of the section where there is a topographical high.

29. This is the surface anomaly data that has been enhanced to show where “harder” surfaces are relative to “soft” or muddy surfaces. The bright orange areas represent hard surfaces. Please notice the bright oval area at the upper part of the slide.This is the surface anomaly data that has been enhanced to show where “harder” surfaces are relative to “soft” or muddy surfaces. The bright orange areas represent hard surfaces. Please notice the bright oval area at the upper part of the slide.

30. This is an enlargement of the topographic high. The center area is a known outcrop of hydrate. This area has been surveyed by the navy submarine NR-1 and samples have been taken. Gas hydrate has been confrimed at the surface and just below over the entire red area and the yellow area. I am now going to show you the cross section labelled B’.This is an enlargement of the topographic high. The center area is a known outcrop of hydrate. This area has been surveyed by the navy submarine NR-1 and samples have been taken. Gas hydrate has been confrimed at the surface and just below over the entire red area and the yellow area. I am now going to show you the cross section labelled B’.

31. Below the surface in this viewgraph, you can see the angles of the sediments and the wash out area in the middle. This washout area is interpreted to be sediments mixed with gas.In the center, near the green marker, is where hydrate has been observed at the surface. As I mentioned earlier, we now have a proposal from Dr. Harry Roberts to visually look at the hydrates. He will also look at the underlying geology and the surface expression to try and relate the seismically observed characteristics with the observed outcrop and hopefully develop a better understanding of the criteria needed to identify hydrate outcrops and the associated chemosynthetic communities. This information will aid personnel in the Leasing and Environment section to better determine the location of sensitive communities and apply mitigations more appropriately. Below the surface in this viewgraph, you can see the angles of the sediments and the wash out area in the middle. This washout area is interpreted to be sediments mixed with gas.In the center, near the green marker, is where hydrate has been observed at the surface. As I mentioned earlier, we now have a proposal from Dr. Harry Roberts to visually look at the hydrates. He will also look at the underlying geology and the surface expression to try and relate the seismically observed characteristics with the observed outcrop and hopefully develop a better understanding of the criteria needed to identify hydrate outcrops and the associated chemosynthetic communities. This information will aid personnel in the Leasing and Environment section to better determine the location of sensitive communities and apply mitigations more appropriately.

32. In conclusion, interest in gas hydrates is multifaceted. While there are many scientifically interesting aspects to investigate, the areas of greatest interest to MMS involve safety and protection of sensitive communities. Both have been and are being addressed. In the long term, and this means at the earliest 2015, and if the extraction of hydrates from the outer continental shelf becomes economically feasible, then MMS will need to understand new technology, be able to identify and value the resource for royalty purposes, and assess the environmental impacts from the extraction procedures.In conclusion, interest in gas hydrates is multifaceted. While there are many scientifically interesting aspects to investigate, the areas of greatest interest to MMS involve safety and protection of sensitive communities. Both have been and are being addressed. In the long term, and this means at the earliest 2015, and if the extraction of hydrates from the outer continental shelf becomes economically feasible, then MMS will need to understand new technology, be able to identify and value the resource for royalty purposes, and assess the environmental impacts from the extraction procedures.