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40-478: About 4 kilometers east of the main village of Friedeburg, near the small village named Etzel, one of Europe's largest salt domes is located. This geological feature is part of the 240 million years old Zechstein Group formations. The salt dome, with a volume of 46 million cubic metres, houses important natural gas storages and crude oil storages. In February, 2022, the government of Lower Saxony decided to subsidize

80-441: A "free" by-product associated with financially more lucrative coal or liquid hydrocarbon recovery that had to be dealt with. The growth of international gas markets, infrastructure and supply chains have done much to change this. It is also becoming more of a standard practice to: Today, it is financially viable to develop even relatively small hydrocarbon reservoirs containing non-associated gas (i.e. with little or no oil) close to

120-558: A form of raw natural gas ). Global statistics from year 2012 show that the majority (58%) of this gas was re-injected for storage and to help maintain well pressure, 27% was sent to consumption markets, and the remaining 15% was vented or flared near the well site. 100 million tons of the vented associated gas was combusted in flares worldwide, equal to about 3-4% of all gas produced from oil and gas wells. The flared gas yielded nearly 350 million tons of CO 2 -equivalent emissions of greenhouse gases , contributing about 1% of

160-658: A formation is permeated with boreholes prior to and/or during extraction work, and the so-called firedamp gases allowed to vent as a safety measure. Also during work, methane enters the ventilation air system at concentrations as high as 1%, and is usually freely exhausted from the mine opening. Such ventilation air methane (VAM) is the largest source of methane from all operating and decommissioned coal mines worldwide. Substantial methane also continues to desorb from coal placed into storage and from abandoned mines. The U.S. Environmental Protection Agency projects that by year 2020, global methane releases from coal mines throughout

200-435: A layer thick enough for the formation of salt diapirs , indicating that a sustained period of episodic flooding and evaporation of the basin must occur. Over time, the layer of salt is covered with deposited sediment , becoming buried under an increasingly large overburden . Previously, researchers believed that the compaction of overlying sediment and subsequent decrease in buoyancy led to salt rising and intruding into

240-415: A market or export route, as well as large, remote accumulations. Fossil gas was recently promoted by some industry advocates and policy makers as a "bridge fuel" that could yield the least waste, and thus environmental damage and accompanying economic losses, during the transition from finite fossil-fuel reserves to more sustainable sources. However, the actual volumes of methane released cumulatively over

280-530: A process known as diapirism . Salt domes can have unique surface and subsurface structures, and they can be discovered using techniques such as seismic reflection . They are important in petroleum geology as they can function as petroleum traps . Stratigraphically, salt basins developed periodically from the Proterozoic to the Neogene . The formation of a salt dome begins with the deposition of salt in

320-421: A restricted basin . In these basins, the outflow of water exceeds inflow. Specifically, the basin loses water through evaporation , resulting in the precipitation and deposition of salt. While the rate of sedimentation of salt is significantly larger than the rate of sedimentation of clastics , it is recognized that a single evaporation event is rarely enough to produce the vast quantities of salt needed to form

360-553: A solution and we can implement it right now." A 2023 Energy and Emissions Research Lab report discusses challenges in meeting the 2030 methane reduction targets under the Global Methane Pledge, due to uncertainties in emission levels from oil and gas operations. The research, which centers on Alberta, Canada —the Canadian province with the largest oil and gas-industry—presents a methane inventory for 2021 that exceeds

400-599: Is home to most of the US Strategic Petroleum Reserve . Avery Island was formed by a salt dome. During the break-up of the south Atlantic, Aptian (Lower Cretaceous) age salt was deposited within the area of thinned crust on both the Brazilian and conjugate Angola/Gabon margins forming many salt domes. During the Messinian salinity crisis ( Late Miocene ), thick salt layers were formed as

440-661: Is the primary financial objective, and very little is unwanted compared to the gas produced in oil fields or coal mines. The majority of venting emissions instead occur during the pipeline transport to trading & distribution hubs , refineries , and consumer markets. The U.S. Department of Energy reports that a majority of the venting within U.S. gas industry operations in year 2017 occurred at compressor stations and from pneumatically operated controllers and regulators . Improved maintenance strategies and advanced equipment technologies either exist or are being developed to reduce such venting. Global tracking estimates from

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480-516: The Mediterranean Sea dried out. Later deposition, once the sea refilled, triggered the formation of salt domes. Gas venting Gas venting , more specifically known as natural-gas venting or methane venting , is the intentional and controlled release of gases containing alkane hydrocarbons - predominately methane - into Earth's atmosphere. It is a widely used method for disposal of unwanted gases which are produced during

520-587: The Paradox Formation forms salt domes throughout the Paradox Basin in the US, which extends from eastern Utah , through southwestern Colorado into northwestern New Mexico . An example of an emergent salt dome is at Onion Creek, Utah / Fisher Towers near Moab, Utah. A Paradox Formation salt body that has risen as a ridge through several hundred meters of overburden, predominantly sandstone . As

560-640: The 33 billion tons of carbon dioxide (CO 2 ) released from the burning of all fossil fuels . Flare Gas Recovery Systems (FGRS) are being increasingly implemented as a more economically productive alternative to flaring. Preferably, all of the unwanted gas would at least be abated in gas flares, but this has not been achieved in practice. For example, the vented volumes from individual wells are sometimes too small and intermittent, and may present other difficulties (e.g. high concentrations of contaminants ) that make flaring more technically and economically challenging. Also, gas will continue to effervesce from

600-494: The IEA during year 2019 further indicate that about 23 million tons of methane were vented from all gas industry segments, including onshore conventional gas , offshore gas , unconventional gas , and downstream gas activities. When including the amount released from fugitive emissions, the estimated total is about 43 million tons. Associated petroleum and coal mining gases were sometimes considered troublesome, dangerous, low value:

640-560: The United States. Several countries use solution mining to form caverns for holding large amounts of oil or gas reserves . The caprock above the salt domes can contain deposits of native sulfur (recovered by the Frasch process ). They can also contain deposits of metals, sodium salts , nitrates , and other substances, which can be used in products such as table salt and chemical de-icers . Salt domes occur in many parts of

680-402: The accumulation of sediments around the diapir contribute to its growth and eventually form into a dome. Some salt domes can be seen from Earth's surface. They can also be located by finding unique surface structures and surrounding phenomena. For instance, salt domes can contain or be near sulfur springs and natural gas vents . Some salt domes have salt sheets that extrude from the top of

720-538: The amount released from incomplete gas flares and fugitive emissions, the estimated total is about 37 million tons. Matthew Johnson, from the Energy and Emissions Research Lab (EER) at Carleton University in Ottawa, Ontario, Canada, said in a December 2023 interview that—contrary to common beliefs—venting, particularly from heavy oil facilities designed for normal operations, is the primary source of methane emissions in

760-529: The central and southern North Sea , extending eastwards into Germany. Upper Triassic salt forms salt domes in the Essaouira Basin onshore and offshore Morocco. An equivalent salt sequence, the Argo Formation, is associated with salt dome formation on the conjugate Nova Scotia margin . The Gulf Coast is home to over 500 salt domes formed from Middle Jurassic Louann Salt . This region

800-662: The crude oil for some time after it is moved into storage tanks at the well site and transported elsewhere. This gas may also be routed to a flare stack, utilized, or designed to escape without mitigation through vents or pressure regulators . Global tracking estimates from the International Energy Agency (IEA) during year 2019 indicate that an additional 32 million tons of methane were vented without abatement from all petroleum extraction; including onshore conventional oil , offshore oil , unconventional oil , and downstream oil activities. When including

840-409: The dome, forming pockets and reservoirs of petroleum and natural gas (known as petroleum traps) . In 1901, an exploratory oil well was drilled into Spindletop Hill near Beaumont , Texas. This led to the discovery of the first salt dome, revealed the importance of salt to the formation of hydrocarbon accumulations, and produced enough oil for petroleum to become an economically feasible fuel for

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880-508: The dome; these are referred to as salt plugs. These plugs can coalesce to form salt canopies, which can then be remobilized by roof sedimentation, with the most prominent example in the northern Gulf of Mexico basin . Another structure that can form from salt domes are salt welds . These occur when the growth of a dome is prevented by an exhausted supply of salt, and the top and bottom contacts merge. Salt domes have also been located using seismic refraction and seismic reflection . The latter

920-437: The expansion of offshore petroleum exploration efforts led to the discovery of numerous salt domes soon after World War II . Salt domes are the site of many of the world's hydrocarbon provinces. The rock salt of the salt dome is mostly impermeable, so, as it moves up towards the surface, it penetrates and bends existing rock along with it. As strata of rock are penetrated, they are, generally, bent upwards where they meet

960-893: The extraction of coal and crude oil . Such gases may lack value when they are not recyclable into the production process, have no export route to consumer markets, or are surplus to near-term demand. In cases where the gases have value to the producer, substantial amounts may also be vented from the equipment used for gas collection, transport , and distribution. Gas venting contributes strongly to climate change . Nevertheless, many individual cases are sufficiently small and dispersed to be deemed "safe" with regard to immediate health hazards. Large and concentrated releases are usually abated with gas flares to produce relatively less-harmful carbon dioxide gas. Gas venting and flaring that are performed as routine practices are especially wasteful and may be eliminated in many modern industrial operations, where other low-cost options are available to utilize

1000-491: The federal government's objective of achieving net-zero carbon emissions in the sector by 2050. Given that the oil and gas industry contributes to 28 percent of Canada's emissions, these proposed changes signal a significant effort to address environmental concerns and combat climate change. Substantial amounts of methane-rich gas are trapped and adsorbed within coal formations, and are unavoidably desorbed in association with coal mining . In some cases of sub-surface mining,

1040-465: The gas. Gas venting is not to be confused with similar types of gas release, such as those from: Gas venting should also not be confused with "gas seepage" from the earth or oceans - either natural or due to human activity. Petroleum extraction from oil wells , where acquiring crude oil is the primary and sometimes sole financial objective, is generally accompanied by the extraction of substantial amounts of so-called associated petroleum gas (i.e.

1080-632: The last century, and is already a factor 2.5 greater than at any point in the last 800,000 years. Methane is a potent warming gas despite its lower abundance compared to atmospheric carbon dioxide. Atmospheric methane is responsible for at least one-quarter and as much as one-third of the changes in radiative forcing that drive near-term climate warming . The ethane , propane , and butane components of natural gas have much shorter atmospheric lifetimes (ranging from about 1 week to 2 months) compared to methane (1-2 decades) and carbon dioxide (1-2 centuries). They consequently do not become well-mixed into

1120-491: The official federal inventory by 1.5 times. The study underscores that nearly two-thirds of emissions—primarily stemming from uncontrolled tanks, pneumatics, and unlit flares, result from gas venting—indicating substantial opportunities for mitigation. Notably, methane intensities in Alberta are four times higher than those in neighboring British Columbia, highlighting the necessity for independent monitoring and reporting ensuring

1160-459: The oil and gas industry alone rose from about 63 to 82 million tons over years 2000 thru 2019; an average increase of about 1.4% per year. Globally, the IEA estimates that the geologic extraction of coal, crude oil, and natural gas is responsible for 20% of all methane emissions. Other researchers have found evidence that their contribution may be substantially higher; 30% or greater. Methane's atmospheric concentration has nearly doubled over

1200-540: The oil and gas industry. Johnson stresses the urgency of swiftly retrofitting oil and gas sites, considering that the associated costs are reasonable, based on various studies. The estimated cost for retrofitting for the total industry in Canada is estimated at $ 3.3 billion between 2027 and 2040 for implementing both venting and flaring requirements in the . Jonson said that while fossil fuels are not going to be phased out "overnight", "when it comes to methane emissions, we have

1240-415: The overburden due to its ductility , thereby creating a salt diapir. However, after the 1980s, the primary force that drives the flow of salt is considered to be differential loading. Differential loading can be caused by gravitational forces ( gravitational loading ), forced displacement of salt boundaries ( displacement loading ), or thermal gradients ( thermal loading ). The flow of the salt overcomes

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1280-406: The realization of underground hydrogen storages there as well. This East Frisia article is a stub . You can help Misplaced Pages by expanding it . This Wittmund (district) location article is a stub . You can help Misplaced Pages by expanding it . Salt dome A salt dome is a type of structural dome formed when salt (or other evaporite minerals) intrudes into overlying rocks in

1320-553: The salt body rose, the overburden formed an anticline (arching upward along its center line) which fractured and eroded to expose the salt body. Offshore northern Norway in the southwestern Barents Sea , thick Upper Carboniferous – Lower Permian salt was deposited, forming salt domes in the Hammerfest and Nordkapp basins. In northwest Europe Upper Permian salt of the Zechstein Group has formed salt domes over

1360-406: The strength of the overburden as well as boundary friction aided by overburden extension , erosion, thrust faults , ductile thinning, or other forms of regional deformation. The vertical growth of salt formations creates pressure on the upward surface, causing extension and faulting . Once the salt completely pierces the overburden, it can rise through a process known as passive diapirism where

1400-600: The success of emission reduction initiatives. Gas venting in the oil and gas industry has gained attention in Alberta, Canada, particularly in light of proposed legislative changes aimed at reducing methane emissions. Federal Environment Minister Steven Guilbeault presented a plan during the 2023 United Nations Climate Change Conference in Dubai , outlining a national cap-and-trade system to curb emissions without hindering production. The proposed framework aims to cap 2030 emissions at 35 to 38 percent below 2019 levels, aligning with

1440-400: The supply chain have a near-term climate warming impact which already rivals, and may grow to exceed, that from using coal and oil. Venting and other releases of gaseous hydrocarbons have increased steadily throughout the industrial age alongside the rapid growth in production and consumption of fossil fuels. The International Energy Agency estimates that total annual methane emissions from

1480-674: The surface are also sometimes permeated with wells to extract and capture the methane, in which event it is classified as a form of unconventional gas . Such coalbed methane capture can reduce the volume of gas seepage that would otherwise occur naturally, while in-turn adding emissions of carbon dioxide once the fuel is utilized elsewhere. Global tracking estimates from the IEA during 2019 suggest that about 40 million tons of methane were released from all activities related to coal mining. This total amount includes all vented, fugitive and seepage emissions. In gas fields, acquiring non-associated petroleum gas (i.e. another form of raw natural gas)

1520-860: The world where there is a sufficiently thick layer of rock salt developed. In the Middle East, the upper Neoproterozoic salt of the Hormuz Formation is associated with widespread salt dome formation in most parts of the Persian Gulf and onshore in Iran, Iraq, United Arab Emirates , and Oman . The thicker salt is found in a series of basins: the Western Gulf, the Southern Gulf, and the Oman salt basins. Pennsylvanian age salt of

1560-567: The world will exceed 35 million tons or 800 million tons of CO 2 -equivalent emissions, and account for 9% of all global methane emissions . China contributes over 50% of the total, followed by the United States (10%) and Russia (7%), and then by Australia, Ukraine, Kazakhstan, and India (3-4% each). About 200 mines across a broad scope of countries had implemented technology by the year 2015 to capture about 3 million tons of methane, either for economic use or for abatement in gas flares or thermal oxidizers . Outcroppings, seams, or formations near

1600-512: Was developed based on techniques from the former and is more effective. Seismic refraction uses seismic waves to characterize subsurface geologic conditions and structures. Seismic reflection highlights the presence of a stark density contrast between the salt and surrounding sediment. Seismic techniques are particularly effective as salt domes are typically depressed blocks of crust bordered by parallel normal faults ( graben ) that can be flanked by reverse faults. Advances in seismic reflection and

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