scholarly journals Parageneses of cryogenic formations of gas emission funnels (Part 1). Morphology of cryogenic formations

Author(s):  
Aleksandr Nikolaevich Khimenkov ◽  
Andrei Viktorovich Koshurnikov ◽  
Julia Viktorovna Stanilovskaya

The subject of this research is the cryogenic formations found in gas emission funnels in the north of Western Siberia. The object of this research is cryogenic processes that prepare the explosion, which forms a gas emission funnel. The study of cryogenic structures that shape the walls of gas emission funnels is based on the structural-genetic analysis, which reveals the peculiarities of the initial cryogenic structure of frozen rock, as well as the cryogenic textures modified as a result of dynamic metamorphism. The authors examine such aspects of the topic as the general orientation of plastic and explosive deformations under the influence of high pressure. Analysis is conducted on the role of intra-ground gas filtration in transformation of the initial cryogenic structure. Special attention is given to the patterns of emergence and development of the local geodynamic system that ultimately substantiates the formation of gas emission funnel. The novelty of this research consists in the establishment of paragenetic relations between the processes of gas filtration and deformations of gas-saturated ice surface material (from viscoplastic motion to brittle fracture). The main conclusions are as follows: such external influences as increase in the temperature or pressure change thermodynamic conditions, which lead to multi-phase structural transformation of the initial cryogenic structure of the cryolithic zone; a series of plastic and explosive deformations instigates the intense heat and mass transfer, redistributing the substance in the liquid, solid and gaseous state; in frozen rocks, ice is the most deformable component, thus, most information on the processes preceding the formation of gas funnels can be acquired by studying the morphology of cryogenic formations observed in the walls of the funnels, as well as in the unthawed fragments of frozen rocks thrown to the surface. The authors’ special contribution lies in examination of the complete lifecycle of the development of selected geosystems, from the initial stage –  formation of conditions for decomposition of the gas hydrates, to the final stage – explosion and emission of ice surface material.

Author(s):  
М.О. Leibman ◽  
Yu.А. Dvornikov ◽  
I.D. Streletskaya ◽  
А.V. Khomutov ◽  
А.I. Kizyakov ◽  
...  

2019 ◽  
Vol 46 (11) ◽  
pp. 5759-5767 ◽  
Author(s):  
Mark G. Fox‐Powell ◽  
Gordon R. Osinski ◽  
Daniel Applin ◽  
Jessica M. Stromberg ◽  
Fernando Gázquez ◽  
...  

1987 ◽  
Vol 9 ◽  
pp. 211-214
Author(s):  
K. Steffen

Profiles of the ice cover in the North Water area were obtained in the winter of 1980/81 by using low-level infrared thermometry. The flight measurements were carried out from December to March. The statistical analysis of the sea ice surface temperature was carried out to yield distributions, frequencies and widths of fractures. Ice-free as well as ice-covered fractures with a maximum ice thickness of 0.4 m were analysed. Typical fracture frequencies were 0.25 per km for Lancaster Sound and 0.14 per km for Baffin Bay and the North Water area, with 90% of fractures being less than 0.6 km wide. From December to March, the fractures occupied 8.8% of the Ice cover in the North Water area, 8.7% along the Baffin Bay profile and 10% in the Lancaster Sound. In the North Water area the distance (y) between fractures for different fracture widths (x) is an exponential function of the form y=Aexp(ax) (A,a are constants), for fractures between 50 and 800 m wide. In the North Water area during winter, fractures of all widths occur 5 times more frequently than in M’Clure Strait and about 7 times more frequently than in southern Beaufort Sea. The heat loss in Lancaster Sound at the ice-air interface was found to be 40 to 100% larger due to the fractures compared to a fast ice situation in the same winter.


1979 ◽  
Vol 24 (90) ◽  
pp. 483
Author(s):  
David J. Drewry

Abstract Systematic radio echo-sounding during three seasons since 1971–72 has produced data on the configuration of the ice sheet in East Antarctica. In the sector extending inland from southern Victoria Land, the ice sheet exhibits a large ridge which drives ice towards David Glacier in the north and Mulock and Byrd Glaciers to the south. Within 100 km of the McMurdo dry-valley region soundings along ten sub-parallel lines (c. 10 km apart) provides detail on ice surface and flow patterns at the ridge tip. A small surface dome lies just inland of Taylor Glacier. The surface drops by 100 m or more before rising to join the major ridge in East Antarctica.


1971 ◽  
Vol 10 (59) ◽  
pp. 245-254 ◽  
Author(s):  
R. A. Souchez

AbstractThe north-west margin of the main ice cap in south-western Ellesmere Island is fringed by ice-cored moraines. The formation of these moraines seems to be more complex than simple upwarping of the foliation bands at the margin of the ice cap. At one locality, where outer and inner zones can be distinguished on the basis of lithological composition, debris in the outer zone is composed of material from farther back under the ice cap than debris in the inner zone. In another locality, localized ridges cross each other independently of the trend of the main ridge.The time required to obtain the quantity of debris forming the moraine at the ice surface is estimated to be between 65 and 300 years.


2019 ◽  
Vol 290 ◽  
pp. 10002
Author(s):  
Cristian Nicolae Eparu ◽  
Sorin Neacsu ◽  
Renata Radulescu ◽  
Alina Petronela Prundurel

Natural gases are a mixture of hydrocarbons which are generally in a gaseous state. Due to the variation in transport parameters (pressure, temperature) and gas composition, there may be sectors where those appear in liquid state, the condensate. The paper presents a system for managing the quantities of fluids from a network in which the liquid state appears. Based on a simulator that includes flash computation, a physical balance of the transport or gathering network can be made.


2001 ◽  
Vol 33 ◽  
pp. 457-473 ◽  
Author(s):  
Josefino C. Comiso

AbstractRecent observations of a decreasing ice extent and a possible thinning of the ice cover in the Arctic make it imperative that detailed studies of the current Arctic environment are made, especially since the region is known to be highly sensitive to a potential change in climate. A continuous dataset of microwave, thermal infrared and visible satellite data has been analyzed for the first time to concurrently study in spatial detail the variability of the sea-ice cover, surface temperature, albedo and cloud statistics in the region from 1987 to 1998. Large warming anomalies during the last four years (i.e. 1995−98) are indeed apparent and spatially more extensive than previous years. The largest surface temperature anomaly occurred in 1998, but this was confined mainly to the western Arctic and the North American continent, while cooling occurred in other areas. The albedo anomalies show good coherence with the sea-ice concentration anomalies except in the central region, where periodic changes in albedo are observed, indicative of interannual changes in duration and areal extent of melt ponding and snow-free ice cover. The cloud-cover anomalies are more difficult to interpret, but are shown to be well correlated with the expected warming effects of clouds on the sea-ice surface. The results from trend analyses of the data are consistent with a general warming trend and an ice-cover retreat that appear to be even larger during the last dozen years than those previously reported.


2017 ◽  
Vol 205 ◽  
pp. 135-146 ◽  
Author(s):  
Yuechen Tan ◽  
Cong Xu ◽  
Dongxue Liu ◽  
Wenliang Wu ◽  
Rattan Lal ◽  
...  

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 85
Author(s):  
Kelly Elimian ◽  
Carina King ◽  
Karin Diaconu ◽  
John Ansah ◽  
Sebastian Yennan ◽  
...  

Introduction: Adamawa and Bauchi are cholera endemic states in the north-east region of Nigeria, each with local government areas classified as cholera hotspots. Ineffective implementation of multi-sectoral cholera interventions in both states could make obtaining the global target for cholera control in Nigeria out of reach. A major contributing factor to this challenge is fragility of the region due to persistent Boko Haram insurgency activities, often characterised by the destruction of health infrastruture and displacement of communities to areas with suboptimal living conditions. Given the complexity of disease control in such a fragile setting, this study aims to systematically examine the barriers and/or facilitators influencing the implementation of existing cholera interventions in these states.   Methods: The study will use a systems dynamic approach. First, we will conduct a health facility survey to determine the current health system capacity to support multi-sectoral cholera interventions, and conduct key informant interviews with purposely selected state and national cholera stakeholders to identify the context-specific facilitators and barriers to the implementation of cholera interventions in these states. We will then conduct nine group model building workshops (four in both the Adamawa and Bauchi states and one in Abuja) among cholera stakeholders similar to those recruited for the interviews. Conclusion: By engaging diverse and relevant cholera stakeholders, including community members, this study has the potential to provide a rich understanding of context-specific factors influencing the implementation of multi-sectoral cholera interventions in a fragile region of Nigeria, with a view to achieve sustainable progress towards cholera control in the country. Moreover, this study could have an impact on the control of other water-borne diarrheagenic diseases in the country.


Author(s):  
V. T. Bolonny

The characteristics of the gas transportation system of Ukraine are presented, the emergency risks of domestic gas transportation pipeline sys­tems are established. The analysis of the accident rate of gas pipeline trans­port in Ukraine and Russia was carried out. Presented technique of deter­mining the emergency pressure in the pipeline, depending on the amount of gas losses from pipeline at the point of its leakage provides an opportunity to determine the volume of gas losses from the pipeline and to evaluate the environmental risks due to emergency situations of gas pipeline transport. This technique makes it possible to calculate the pressure at each point of pipeline under nonstationary conditions caused by changes in pressure at the beginning and at the end of the sector and the emergence of concentrated gas leakage. Based on the results of calculations, a graph of pressure change of the oscillatory process in the gas pipeline caused by jump of pressures at the beginning and at the end of the sector, and the presence of probable lea­kages at the determined point of the trace was constructed. The linear part of the main gas pipelines is the most dangerous object, as all emergency sit­uations are associated with emergency processes of different intensity in the form of gas leakage into the environment and in fact are dangerous when system failures appear. The process and the time period for the formation of the gas pollution zone depend on the amount of gas leakage, its intensity and depth of the gas pipeline. The filtration resistance of the soil as a porous medium, in particular its permeability, have a significant effect on the amount of gas leakage through corrosive orifice. As a result, there is a correlation between the amount of gas losses associated with the leakage, and the laws of its filtra­tion in the surrounding soil. As a result, the effect of gas filtration process in the soil in the event of leakage from pipelines has been investigated. The graphic dependence of change in pressure of the filtration resistance of the medium and the time-changing leakage which are designed for different soil characteristics is obtained.


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