Natural Explosive Processes in the Permafrost Zone

Vlasov, A. N.; Khimenkov, A. N.; Volkov-Bogorodskiy, D. B.; Levin, Yu. K.

doi:10.3103/s0747923918060130

Cited by 5 publications

(11 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Active gas emissions have been observed in various permafrost settings during drilling [4][5][6][7][8], air gas chemistry surveys [9,10], and field monitoring of active layer and water bodies [11][12][13][14][15][16][17][18][19]. Gas emission from permafrost can be explosive (so-called cryovolcanism) and produce deep craters [18][19][20][21][22][23][24][25], which provides additional spectacular evidence for the existence of gas reservoirs in shallow permafrost.…”

Section: Introductionmentioning

confidence: 99%

Conceptual Models of Gas Accumulation in the Shallow Permafrost of Northern West Siberia and Conditions for Explosive Gas Emissions

et al. 2020

View full text Add to dashboard Cite

Gas accumulation and pressurized unfrozen rocks under lakes (sublake taliks) subject to freezing in shallow permafrost may lead to explosive gas emissions and the formation of craters. Gas inputs into taliks may have several sources: microbially-mediated recycling of organic matter, dissociation of intrapermafrost gas hydrates, and migration of subpermafrost and deep gases through permeable zones in a deformed crust. The cryogenic concentration of gas increases the pore pressure in the freezing gas-saturated talik. The gradual pressure buildup within the confined talik causes creep (ductile) deformation of the overlying permafrost and produces a mound on the surface. As the pore pressure in the freezing talik surpasses the permafrost strength, the gas-water-soil mixture of the talik erupts explosively and a crater forms where the mound was. The critical pressure in the confined gas-saturated talik (2–2.5 MPa for methane) corresponds to the onset of gas hydrate formation. The conditions of gas accumulation and excess pressure in freezing closed taliks in shallow permafrost, which may be responsible for explosive gas emissions and the formation of craters, are described by several models.

show abstract

Section: Introductionmentioning

confidence: 99%

Conceptual Models of Gas Accumulation in the Shallow Permafrost of Northern West Siberia and Conditions for Explosive Gas Emissions

et al. 2020

View full text Add to dashboard Cite

show abstract

“…21 Evidence of this process is most clearly seen in the field images of GEC-1 (Yamal crater) and GEC-17 crater, in the form of upwardly deformed (convex) ice and clay loam permafrost layers, traces of gassy fluid flow, and coalescing cavities inside the exposed interiors. 13,16 We further propose that the GEC forms when the accumulating subsurface gas pressure exceeds the sum of the tensile strength and lithostatic pressure of the overburden, causing an explosion.…”

Section: Introductionmentioning

confidence: 98%

“…The resulting craters, however, tend to be a few meters in width and depth and are still located at the top of the ice-cored mound. 13 Siberian GECs are much larger in diameter and remove the majority of the preexisting mound. They are also deeper and more funnel shaped than pingo craters.…”

Section: Introductionmentioning

confidence: 99%

“…Thus, the distinct morphologies alone suggest that GECs and pingos are formed through different processes. 13 After assessing the broader geomorphological settings of five Siberian GECs, Kizyakov et al 5 argued that GECs are unlikely to have formed via ice-rich cores similar to pingos. They found that four GECs were located on slopes, which are not appropriate for the formation of a closed talik that could produce an ice-cored mound.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Formation of the Siberian Yamal gas emission crater via accumulation and explosive release of gas within permafrost

Schurmeier,

Brouwer,

Fagents

2023

Permafrost & Periglacial

View full text Add to dashboard Cite

The Arctic landscape has experienced many dramatic forms of change due to anthropogenic warming. Large crater‐like forms surrounded by fragmented blocks scattered outward to great distances with precursor mounds appeared in the continuous permafrost zone of the Yamal and Gydan peninsulas of Western Siberia. The morphologies of these craters, in addition to the abundant evidence of active and intense gas emissions across the region, indicate that they formed due the subsurface accumulation, pressurization, and explosive release of gasses trapped within the permafrost. Therefore, these craters were termed “gas emission craters” (GEC). However, some have suggested that in addition to gas accumulation, these features form in a manner similar to ice‐cored pingos and require pressurization due to the freezing of subsurface ice. This is despite the fact that not all GECs form in areas conducive to pingo‐like ice accumulation. Here, we test whether the pressurization and explosive release of methane gas alone can reproduce the observed morphology of the first‐discovered and most intensely studied GEC, Yamal crater. We use the available field and satellite data to constrain the initial dimension parameters of a model of the explosion process and consider several plausible configurations for the unknown interior cavity shape, the overlying permafrost cap thickness, and gas chamber volume. The explosion process is modeled in phases: gas migrates upward and accumulates in the subsurface until the gas pressure fractures the overlying cap, the expanding gas and cap blocks are initially accelerated outward together, and then the blocks are launched as projectiles. The sizes and locations of the ejected blocks found at Yamal crater are used to determine the initial gas pressures required to launch those projectiles to the observed locations. Finally, we estimate the amount of gas released in each of the multiple model runs testing different plausible internal cavity geometries. For the range of plausible block sizes and densities, and a subset of gas chamber volumes considered, we find that the gas pressure (0.6–2.6 MPa) required to launch the Yamal crater blocks to their observed distances was within the range of the sum of the ice/permafrost tensile strength and the lithostatic pressure (0.22–2.87 MPa). Thus, the observed blocks could have been launched by the energy required to fracture and displace the overlying permafrost cap. We show that the mechanism of formation of this GEC does not require pressure from the freezing of ice in the subsurface to crack and explode the overlying permafrost—gas pressure alone can produce these GECs. We expect that as our planet warms, the Siberian permafrost will continue to warm, weaken, and release gasses such as the greenhouse gas methane, and contribute to a permafrost carbon‐positive feedback cycle that would lead to the formation of even more explosive GECs.

show abstract

“…Active gas emission from the Arctic permafrost was observed during gas surveys of the near-surface atmosphere [8,11], the active layer, and water bodies [10,[12][13][14][15][16][17][18][19]. Crater features on the surface record explosive emission of deep methane [20][21][22][23][24][25][26].…”

Section: Introductionmentioning

confidence: 99%

Evidence of Gas Emissions from Permafrost in the Russian Arctic

et al. 2020

View full text Add to dashboard Cite

The active emission of gas (mainly methane) from terrestrial and subsea permafrost in the Russian Arctic has been confirmed by ample evidence. In this paper, a generalization and some systematization of gas manifestations recorded in the Russian Arctic is carried out. The published data on most typical gas emission cases have been summarized in a table and illustrated by a map. The tabulated data include location, signatures, and possible sources of each gas show, with respective references. All events of onshore and shelf gas release are divided into natural and man-caused. and the natural ones are further classified as venting from lakes or explosive emissions in dryland conditions that produce craters on the surface. Among natural gas shows on land, special attention is paid to the emission of natural gas from Arctic lakes, as well as gas emissions with craters formation. In addition, a description of the observed man-caused gas manifestations associated with the drilling of geotechnical and production wells in the Arctic region is given. The reported evidence demonstrates the effect of permafrost degradation on gas release, especially in oil and gas fields.

show abstract

Natural Explosive Processes in the Permafrost Zone

Cited by 5 publications

References 2 publications

Conceptual Models of Gas Accumulation in the Shallow Permafrost of Northern West Siberia and Conditions for Explosive Gas Emissions

Conceptual Models of Gas Accumulation in the Shallow Permafrost of Northern West Siberia and Conditions for Explosive Gas Emissions

Formation of the Siberian Yamal gas emission crater via accumulation and explosive release of gas within permafrost

Evidence of Gas Emissions from Permafrost in the Russian Arctic

Contact Info

Product

Resources

About