Methane chimney
Encyclopedia
A methane chimney or gas chimney is a rising column of natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...

, mainly methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

 within a water or sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....

 column. Large deposits of frozen methane
Methane clathrate
Methane clathrate, also called methane hydrate, hydromethane, methane ice, "fire ice", natural gas hydrate or just gas hydrate, is a solid clathrate compound in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice...

, when thawing, release gas into the environment. In cases of sub-sea permafrost
Permafrost
In geology, permafrost, cryotic soil or permafrost soil is soil at or below the freezing point of water for two or more years. Ice is not always present, as may be in the case of nonporous bedrock, but it frequently occurs and it may be in amounts exceeding the potential hydraulic saturation of...

, the methane gas may be dissolved in the seawater before reaching the surface. However, in a number of sites around the world, these methane chimneys release the gas directly into the atmosphere
Atmosphere
An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...

, contributing to global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...

. In some locations along Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

’s northern coast, methane rising from the sea floor to the surface has caused the sea to foam. In hydrocarbon exploration, gas chimneys revealed on seismic reflection data
Reflection seismology
Reflection seismology is a method of exploration geophysics that uses the principles of seismology to estimate the properties of the Earth's subsurface from reflected seismic waves. The method requires a controlled seismic source of energy, such as dynamite/Tovex, a specialized air gun or a...

 are indicators of active gas migration and a working petroleum system.

Trees as methane chimneys

Trees in swamp
Swamp
A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...

y, low-laying areas can actually conduct methane produced in soils up through their stems and out their leaves. It has been known for years that plants in bog
Bog
A bog, quagmire or mire is a wetland that accumulates acidic peat, a deposit of dead plant material—often mosses or, in Arctic climates, lichens....

s and marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....

es also act in this way. This accounts for approximately 60 teragrams, or about 10% of global annual production.

Known sites

  • North coast of Russia
  • Golfo Dulce
    Golfo Dulce
    Golfo Dulce may refer to:* Gulf of Dulce, the name of an inlet in Costa Rica which also is known as 'Golfo Dulce'.* Lake Izabal, the largest lake in Guatemala which also is known as 'Golfo Dulce'....

    , Costa Rica
    Costa Rica
    Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....

  • Bering Sea
    Bering Sea
    The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....

  • Northern coast of Siberia
    Siberia
    Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...


See also

  • Clathrate gun hypothesis
    Clathrate gun hypothesis
    The clathrate gun hypothesis is the popular name given to the hypothesis that rises in sea temperatures can trigger the sudden release of methane from methane clathrate compounds buried in seabeds and permafrost which, because the methane itself is a powerful greenhouse gas, leads to further...

  • Arctic methane release
    Arctic methane release
    Arctic methane release is the release of methane from seas and soils in permafrost regions of the Arctic, as part of a more general release of carbon from these soils and seas. Whilst a long-term natural process, it may be exacerbated by global warming. This results in a weak positive feedback...

  • Methane clathrate
    Methane clathrate
    Methane clathrate, also called methane hydrate, hydromethane, methane ice, "fire ice", natural gas hydrate or just gas hydrate, is a solid clathrate compound in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice...

  • Clathrate hydrate
    Clathrate hydrate
    Clathrate hydrates are crystalline water-based solids physically resembling ice, in which small non-polar molecules or polar molecules with large hydrophobic moieties are trapped inside "cages" of hydrogen bonded water molecules...

  • Runaway climate change
    Runaway climate change
    Runaway climate change describes a theoretical scenario in which the climate system passes a threshold or tipping point, after which internal positive feedback effects cause the climate to continue changing without further external forcings...

  • Global warming
    Global warming
    Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...

  • Hydrothermal vent
    Hydrothermal vent
    A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots. Hydrothermal vents exist because the earth is both...


External links

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