Gas Eruption Research Articles

Short-term earthquake prediction in Kamchatka using low-frequency magnetic fields

This paper is devoted to a method of short-term earthquake (EQ) prediction in Kamchatka, Russia. Properties of low-frequency magnetic fields are the basics of the method, and we used two seismo-electromagnetic phenomena in the EQ prediction: 1. seismo-ionospheric depression in the frequency range of 0.01–0.1 Hz (ULF depression), 2. seismo-atmospheric radiation in the frequency range of 1–30 Hz (ULF/ELF radiation). It is now generally accepted that gas eruption before an EQ causes these ULF/ELF phenomena. We propose a hypothesis that gas emanates from the area in the bottom of Kuril–Kamchatka or Aleutian trenches closest to the epicenter of a forthcoming EQ. The three parameters of an EQ are (i) when (time), (ii) where (position) a next EQ is coming with (iii) how big (magnitude) in the short-term EQ prediction. Position of the source of atmospheric radiation gives an estimate of the epicenter location. Then, we estimate the local magnitude in consequence of its statistical dependence on ULF depression and epicenter distance. Date of a coming EQ is determined by the statistical dependence of delays of EQs relative to the dates of their precursors. The result of application of this method to real magnetic field data is illustrated by official prediction processes during a period of March–May 2016. Limits and possible errors of the method as well as methods to enhance the reliability of the prediction are discussed.

Influence of shallow gas on the geotechnical properties of pockmark soil: A case study in the East China Sea

Several incidents involving damage to submarine pipelines indicate that there will be potential hazards for many submarine structures if the geotechnical properties of the soil in pockmarks remain unclear. Based on a geophysical survey, geological drilling, in-situ measurement, and shallow gas eruption experiment, two large pockmarks near the Zhongjieshan Archipelago in the East China Sea were analyzed comprehensively. The geophysical and in-situ data indicated that the soil below the two pockmarks contains free or dissolved shallow gas, which continues to migrate upward from the deep zones, but there is no high-pressure gas reservoir in the pockmark soil. In-situ piezocone data, geotechnical results, and shallow gas eruption experiments have demonstrated that the pockmark soil has strengthened mechanical properties and zoning characteristics. After analyzing the pockmark soil in the area where the study was conducted, it was concluded that the pockmark soil in this area is not suitable for the accumulation of high-pressure, shallow gas. It also was concluded that the pockmark soil had stronger mechanical properties than virgin sediment due to the compaction of the soil caused by the eruption of the shallow gas. The zoning characteristics of pockmark soil are due to the regional differences in the ability of shallow gas to carry soil particles, which is a new finding that is worthy of attention in off-shore engineering.

Thermal Runaway Characteristics of a Large Format Lithium-Ion Battery Module

The overheat abuse experiment of a 12S1P 37 Ah prismatic Lithium-ion battery module in a nominal energy of 1.65 kWh is conducted in this work. The cell behaviors and characterization in the process of thermal runaway propagation is investigated, including the gas eruption, the fire ejection, the flame combustion, the audio features, and the heat transfer, respectively. In the experiment, the central cell is heated on both sides until the pole temperature moves beyond 300 °C, the thermal runaway undergoes about 43 min and propagates from the central to both sides in the module, and all 12 cells burn. Results show that the first three runaway cells spout gas at first, and, then, emit sound with close amplitudes, frequencies, and energies, about 200 s earlier than the fire ejection. Then, the characteristic of the internal short circuit is the temperature rate zone of 1.0 K/s with time greater than 20 s. Moreover, the proposed thermal propagation coefficient is used to assess the thermal propagation capabilities of the runaway cells on their adjacent cells, and this explains the runaway sequence. It is anticipated that the experimental results can provide the deep understanding, thermal runaway warning, and evaluation method for the module safety design.

Methane eruptions from landfill final cover soil during rainfall events in laboratory experiments

Landfill sites are significant sources of greenhouse gases, particularly methane. It is believed that methane gas eruptions occur under a surface ponding condition during rainfall events. In this study, based on laboratory column experiments in which mixed gas was applied to variably compacted soil columns (10 cm in diameter and 30.5 cm in height) under different rainfall intensities, the effects of the bulk density of the landfill cover soil, the gas injection rates, and the rainfall intensities on the gas eruption phenomenon were investigated. The gas pressure and the water content were monitored during rainfall events. The main results were that (1) an episodic gas compression and eruption cycle was observed under a surface ponding condition, (2) gas eruptions occurred at a higher gas pressure in the soil with a higher dry bulk density, and (3) a higher gas injection rate resulted in continuous gas eruptions. The monitoring of the gas eruption flux and gas concentration in the soil columns, using oxygen-mixed gas as an injected gas, showed that longer gas compression led to higher gas fluxes during the gas eruptions. The concentration of gas in the soil increased over time because of the upward gas flow in accordance with the eruptions. The calculation of the oxygen mass balance indicated that the eruptions had slightly promoted the emission of gas from that which had been stored in the soil prior to the rainfall events.

Дегазация Земли в Арктике: дистанционные и экспедиционные исследования выбросов газа на термокарстовых озерах

Дегазация Земли в Арктике: дистанционные и экспедиционные исследования выбросов газа на термокарстовых озерах

Innovations in a submarine piggyback pipeline project in the East China Sea.

Submarine pipelines are widely used to transport offshore oil and gas. Bundling service pipes and cables with these pipelines can cut costs but such ‘piggyback’ installations can lead to problems with torsion and buckling, particularly at crossings. This paper reports on an innovative anti-rotation device that was successfully implemented in a piggyback pipeline project in the East China Sea. A three-layer concrete mattress together with secondary pipe protection devices was developed for crossings, and advanced engineering analysis was conducted to evaluate risks from shallow gas eruptions.

Triisobutylaluminum additive for liquid hydrocarbon burn enhancement

Metallizing hydrocarbons has received renewed attention as a potential means to increase energy density and burn rate. Particle agglomeration however, is a significant concern, impeding both performance as well as practical implementation due to system fouling. Achieving a metallized hydrocarbon without nanoparticles in suspension would avoid particle agglomeration problems. Previous proof-of-concept work with highly reactive organometallic Al-based clusters stabilized by ligands and dissolved in a hydrocarbon showed such a scheme is not only possible, but the decreased size of the cluster molecules relative to nanoparticles substantially increases reactivity and at least an order of magnitude less active aluminum. To increase understanding of how such burning rate effects manifest with dissolved aluminum, a higher valency alkyl aluminum historically used as a hypergol, triisobutylaluminum (IBu3Al), is dissolved in toluene and isolated droplet combustion is characterized showing up to 60% burning rate increase with 810 mM IBu3Al relative to that of pure toluene attributed specifically to the aluminum content of the additive molecule. Flame emission spectroscopy observing AlO emission supports the vital role of gas eruption and droplet disruption to transport additives into the flame.

Variations in CO2 emissions at a mud volcano at the southern base of Mt Etna: are they due to volcanic activity interference or a geyser-like mechanism?

Mud volcanoes are often associated with large areas of CO2 and CH4 emission that are potentially dangerous due to sudden paroxysmal gas and mud eruptions. Despite the interest in understanding such natural environments, they have not yet been thoroughly investigated and a single interpretative framework remains to be elaborated. This lack of knowledge may be due to the difficulty in measuring in-plume CO2 as there is very little contrast with atmospheric CO2, coupled with the complex organizational strategies required for long-term monitoring. This work features three different methods that were used to evaluate the CO2 flux at the Salinelle mud volcano in the foothills of Mt Etna (Italy), carried out periodically from December 2013 to April 2018. We computed in-plume CO2 flux indirectly using a tunable laser and a portable MultiGAS and, directly, measuring the gas volumetric flux from bubbling pools. The morphological variations of the mud field were recorded using unmanned aerial vehicle (UAV) imagery, which provided information on the migration of vents in relation to the observed variations in measured gas output. Our analysis shows that the three methods gave comparable values, indicating the feasibility of this approach. Our findings suggest a pseudo-cyclical pattern in the bulk CO2 emitted at Salinelle, introducing a new interpretation of the processes involved in mud volcano dynamics. We theorize that the periodic variation of the gas emitted at the Salinelle may be attributed to a “geyser-like” mechanism that may be subject to interruption or changes in magnitude by volcanic or seismic events.

Formation mechanism of large pockmarks in the subaqueous Yellow River Delta

We have identified large pockmarks in an area of approximately 0.3 km2 in the subaqueous Yellow River Delta in the Chengdao Sea. Gas eruption channels not been identified in the sediment layers in this area, and the formation mechanism of these large pockmarks remains unknown. To study the formation mechanism of these large pockmarks, we constructed a layered silty sediment model composed of appropriate geological materials. Then, we calculated the stress, displacement, and excess pore pressure in the layered silty sediment from the surface to a depth of 10 m using the Biot theory. A comparative analysis of the calculated results and the data measured in the field was then performed. Based on these results, we established a new formation mechanism for the large pockmarks. With the occurrence of storm waves, two extreme areas of displacement and excess pore pressure appeared in the layered silty sediment. These extreme values increased quickly in the seabed during the continuous action of storm waves. When the excess pore pressure surpassed the effective stress, the top silty layer instantly liquefied and then reconsolidated. Then, when the pore pressure of the interface position exceeded the effective stress produced by the overlying sediment, the sediments experienced “sand boil” damage. With the repeated action of strong waves, the boundary of the pockmark continued to expand, forming a large and stable pockmark. This work is of great value for further understanding and mitigating marine geologic hazards, such as coastal erosion, silt deposition, and unstable sediment, in the subaqueous Yellow River Delta.

Desorption characterization of methane and carbon dioxide in coal and its influence on outburst prediction

Coal and gas outburst is a dynamic phenomenon with violent eruptions of coal and gas from the working coal seam. It has been proved that the rapid desorption within a short period is necessary for the occurrence of an outburst. Due to limitation of the present test condition, gas desorption characterization for the first 60 s has not been researched sufficiently. In the present study, an experimental apparatus with the ability of high-frequency data collection was developed. Initial desorption characterization of methane and carbon dioxide in coal was experimentally studied. Both the initial desorption characterization of methane and carbon dioxide were experimentally studied with different equilibrium pressures. The desorbed gas pressure was measured at desorption time phase of 0–10 and 45–60 s, besides the initial amount of desorbed gas and initial diffusion velocity of coal gas were calculated to assess their risk of outburst. The results show that the gas pressure for both methane and carbon dioxide increases sharply in the initial time and then levels off, and the total amount of desorbed gas increases with the increasing desorption time. Although the amount of desorption methane is slightly larger than that of carbon dioxide at the beginning, the total amount of desorbed carbon dioxide is significantly larger than that of methane at the desorption process. Therefore, it can be concluded that the coal and carbon dioxide outburst is more dangerous than the coal and methane outburst based on the obtained experimental results.

The Seno Otway pockmark field and its relationship to thermogenic gas occurrence at the western margin of the Magallanes Basin (Chile)

Pockmarks are variably sized crater-like structures that occur in young continental margin sediments. They are formed by gas eruptions and/or long-term release of fluid or gas. So far no pockmarks were known from the Pacific coast of South America between 51°S and 55°S. This article documents an extensive and previously unknown pockmark field in the Seno Otway (Otway Sound, 52°S) with multibeam bathymetry and parametric echosounding as well as sediment drill cores. Up to 31 pockmarks per square kilometer occur in water depths of 50 to >100 m in late glacial and Holocene sediments. They are up to 150 m wide and 10 m deep. Below and near the pockmarks, echosounder profiles image acoustic blanking as well as gas chimneys often crosscutting the 20 to >30 m thick glacial sediments above the acoustic basement, in particular along fault zones. Upward-migrating gas is trapped within the sediment strata, forming dome-like features. Two 5 m long piston cores from inside and outside a typical pockmark give no evidence for gas storage within the uppermost sediments. The inside core recovered poorly sorted glacial sediment, indicating reworking and re-deposition after several explosive events. The outside core documents an undisturbed stratigraphic sequence since ~15 ka. Many buried paleo-pockmarks occur directly below a prominent seismic reflector marking the mega-outflow event of the Seno Otway at 14.3 ka, lowering the proglacial lake level by about 80 m. This decompression would have led to frequent eruptions of gas trapped in reservoirs below the glacial sediments. However, the sediment fill of pockmarks formed after this event suggests recurrent events throughout the Holocene until today. Most pockmarks occur above folded hydrocarbon-bearing Upper Cretaceous and Paleogene rocks near the western margin of the Magallanes Basin, constraining them as likely source rocks for thermogenic gas.

Gas eruption phenomenon happening from Ga-In alloy in NaOH electrolyte

We report a gas eruption phenomenon caused by electrolysis of a liquid Ga-In alloy in an electrolyte, especially NaOH solution. A volcanic eruption-like blowout of gas occurred from the orifice on the alloy surface. In addition to the gas plume, large gas bubbles were also generated and the total gas yield increased as the In ratio was increased. It is found that the destructiveness of the passivation layer on the Ga-In alloy is critical to gas generation. The mechanism of gas eruption can be ascribed to a galvanic interaction between the passivation film and the connected alloy, because of their different electrochemical activity in the electrolyte. Further investigation demonstrated that the lattice of the film expands because of the incorporation of indium, which brings about the decrease in the bandgap and finally enhances more gas generation. These findings regain the basic understanding of a room temperature liquid metal inside an electrolyte.

Evaluation of self-heating models for peracetic acid using calorimetry

Abstract Thermal analysis of peracetic acid (PAA) with respect to the explosive properties was performed using calorimetry. The exothermic characteristics and thermal runaway profiles of PAA solutions were acquired through differential scanning calorimetry (DSC) and vent sizing package 2 (VSP2). The results revealed significant enthalpy changes and gas eruption for PAA solutions that were subjected to free-radical induced and autocatalytic reactions. The reaction kinetics and order of various PAA solutions were elucidated using calorimetry.

Solid-fluid-gas coupling prediction of harmful gas eruption in shield tunneling

In some cities in the south of China, a stratum of explosive gas was often be encountered in shield tunneling, as well as in other countries. However there is no function of explosion-proof function in the shield machine, and it is likely to cause a large number of harmful gases gushing out instantaneously. The harmful gas concentration can exceed the safety alarm value and even lead to explosion. Based on the above issues, solid-fluid-gas three-phase coupling is analyzed with relevant theories and assumptions through FISH language programming in FLAC3D, which originally only has the solid-fluid two-phase coupling function. The prediction of harmful gas eruptions in shield construction is realized. On this basis, a set of real-time monitoring systems for the harmful gases is constructed, which realizes staff evacuation warnings. The research achievement has been successfully applied in a practical project.

Magmatic plumbing systems of the Koryakskii–Avacha Volcanic Cluster as inferred from observations of local seismicity and from the regime of adjacent thermal springs

An analysis of local seismicity within the Avacha–Koryakskii Volcanic Cluster during the 2000–2016 period revealed a sequence of plane-oriented earthquake clusters that we interpret as a process of dike and sill emplacement. The highest magmatic activity occurred in timing with the 2008–2009 steam–gas eruption of Koryakskii Volcano, with magma injection moving afterwards into the cone of Avacha Volcano (2010–2016). The geometry of the magma bodies reflects the NF geomechanical conditions (tension and normal faults, $$S_V>S_{H_{\text{max}}}>S_{h_{\text{min}}}$$ ) at the basement of Koryakskii Volcano dominated by vertical stresses S v , with the maximum horizontal stress $$S_{h_{\text{max}}}$$ pointing north. A CFRAC simulation of magma injection into a fissure under conditions that are typical of those in the basement of Koryakskii Volcano (the angle of dip is 60°, the size is 2 × 2 km2, and the depth is –4 km abs.) showed that when the magma discharge is maintained at the level of 20000 kg/s during 24 hours the fissure separation increases to reach 0.3 m and the magma injection is accompanied by shear movements that occur at a rate as high as 2 × 10–3 m/s, thus corresponding to the conditions of local seismic events with Mw below 4.5. We are thus able to conclude that the use of planeoriented clusters of earthquakes for identification of magma emplacement events is a physically sound procedure. The August 2, 2011 seismicity increase in the area of the Izotovskii hot spring (7 km from the summit of Koryakskii Volcano), which is interpreted as the emplacement of a dike, has been confirmed by an increase in the spring temperature by 10–12°C during the period from October 2011 to July 2012.

Initial desorption characterization of methane and carbon dioxide in coal and its influence on coal and gas outburst risk

Coal and gas outburst is a dynamic phenomenon with violent eruptions of coal and gas from the working coal seam, resulting in economic loss and casualties. It has been proved that rapid desorption within a short period is necessary for occurrence of an outburst. Due to limitation of the present test condition, gas desorption characterization for the first several seconds (0–10s) hasn’t been researched sufficiently. In this study, initial desorption characterization of gas in coal is studied by experiments with methane and carbon dioxide. The most remarkable characteristic of the experimental setup is application of a self-developed real-time data acquisition system with time interval of about 1.6ms, which achieves the goal of collecting enough pressure and temperature data for analysis and calculation. The data is used to study gas pressure variation and calculate initial amount of desorbed gas and initial expansion energy of released gas. From the experimental results, new proof has been found to verify that coal and carbon dioxide outburst is more dangerous than coal and methane outburst.

Probing nanoscale oxygen ion motion in memristive systems

Ion transport is an essential process for various applications including energy storage, sensing, display, memory and so on, however direct visualization of oxygen ion motion has been a challenging task, which lies in the fact that the normally used electron microscopy imaging mainly focuses on the mass attribute of ions. The lack of appropriate understandings and analytic approaches on oxygen ion motion has caused significant difficulties in disclosing the mechanism of oxides-based memristors. Here we show evidence of oxygen ion migration and accumulation in HfO2 by in situ measurements of electrostatic force gradient between the probe and the sample, as systematically verified by the charge duration, oxygen gas eruption and controlled studies utilizing different electrolytes, field directions and environments. At higher voltages, oxygen-deficient nano-filaments are formed, as directly identified employing a CS-corrected transmission electron microscope. This study could provide a generalized approach for probing ion motions at the nanoscale.

Sand volcano generated by a violent degassing from methane-saturated aquifers: The case study of Medolla (Modena, Italy)

Sand volcano is an unusual and remarkable geological feature which forms when water-saturated sand deposits are set in motion by liquefaction and are ejected onto the surface. Commonly it is generated during earthquakes, as a result of liquefaction of waterlogged bodies at shallow depth, often causing wide damages. The generation of a sand volcano however can also occur unrelated to a seismic event. On the 10th of October 2014, near Medolla (Italy) during a Cone Penetration Test, a large amount of natural gas (CO2 and CH4) together with a mixture of water and sand were erupted, creating a sand volcano. The study of this event gives the possibility of understanding the dynamics of sand volcano generation, may enable to prevent other anomalies during future CPT tests and, more importantly, underlines the role that natural gas, stored in a sand aquifer, may play in triggering a liquefaction phenomenon. Our results suggest that episodes of gas eruptions require the onset of very peculiar conditions within the reservoir that feeds the emission. The simulations suggest that a geyser discharging a mixture of gas and water, capable of building a sand volcano, requires the presence of a shallow pressurized reservoir (1.2MPa) where water coexists with a small amount of exsolved gas (a volume fraction of 0.05).The violent degassing occurred in Medolla confirms the role that a free gas phase may have in favoring the mobilization of liquid water and loose deposits, even in the absence of a seismic event.

The influence of magnetic field on the physical explosion of a heavy gas cloud

ABSTRACTRichtmyer–Meshkov (RM) instability arises during the eruption of heavy gas cloud. In this study, we numerically study the effects of magnetic fields on the RM instability induced by the ionised cylindrical and spherical heavy gas cloud eruption using corner transport upwind + constrained transport algorithm. Our numerical results show that magnetic fields can suppress the formation of spike and bubble structures induced by the eruption in both cylindrical and spherical cases. The magnetic pressure of the interface along the perpendicular direction of magnetic field is the main factor to control the distortion of the interface. Even weak magnetic fields can drastically alter the evolution of the cloud and result in different distributions and amplifications of the magnetic pressure, which will affect further transformation of RM instability during the ionised gas eruption. Meanwhile, the magnetic pressure on the interface decreases gradually when the initial magnetic field is relatively large; when the initial magnetic field is small enough, the opposite results will occur.

Plume Modeling Establishes Efficacy, Safety of Gas Extraction From Lake Kivu, Rwanda

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper OTC 27247, “Plume Modeling in Lake Kivu, Rwanda, for a Gas-Extraction Facility,” by Timothy L. Morse, Nicolas F. Ponchaut, and Gary N. Bigham, Exponent, prepared for the 2016 Offshore Technology Conference, Houston, 2–5 May. The paper has not been peer reviewed. Copyright 2016 Offshore Technology Conference. Reproduced by permission. Lake Kivu is unique among East African Rift lakes with high concentrations of dissolved carbon dioxide (CO2) in that it also contains methane (CH4). The dissolved gases constitute a hazard because a vertical disruption of the water could cause gas-laden water to be displaced to shallower depths with lower pressures, allowing the gas to bubble out of solution and triggering a gas eruption. A floating gas-extraction facility has been constructed to extract gas-laden water, separate the methane and some of the CO2, and reinject the degassed water, thus increasing the safety of the lake and simultaneously providing CH4. Introduction Lake Kivu sits along the border between the Democratic Republic of the Congo (DRC) and Rwanda, in the Great Rift Valley region of Africa. The lake is approximately 89 km long, oriented in a north/ south direction, and 48 km wide. The lake is at 1460 m above sea level and has a maximum depth of approximately 485 m in its northern basin. Lake Kivu has an unusual thermal structure. At depths below approximately 80 m, the water temperature increases with depth. However, the water also contains large quantities of dissolved CO2 and salt, with concentrations that increase with depth. The density-increasing effects of CO2 and salt maintain the lake stratification despite the inverted temperature profile. The density structure of the lake is a series of relatively homogeneous mixed zones separated by density-gradient layers. The major mixed zones, beginning at the surface, are referred to as the Biozone, Intermediate Zone, Potential Resource Zone, Upper Resource Zone, and Lower Resource Zone. The Main Density Gradient separates the Potential Resource Zone from the Upper Resource Zone. The Secondary Density Gradient separates the Upper and Lower Resource Zones.