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Journal articles on the topic 'Hyaloclasite'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Eggertsson, Guðjón H., Jackie E. Kendrick, Joshua Weaver, et al. "Compaction of Hyaloclastite from the Active Geothermal System at Krafla Volcano, Iceland." Geofluids 2020 (July 11, 2020): 1–17. http://dx.doi.org/10.1155/2020/3878503.

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Hyaloclastites commonly form high-quality reservoir rocks in volcanic geothermal provinces. Here, we investigated the effects of confinement due to burial following prolonged accumulation of eruptive products on the physical and mechanical evolution of surficial and subsurface (depths of 70 m, 556 m, and 732 m) hyaloclastites from Krafla volcano, Iceland. Upon loading in a hydrostatic cell, the porosity and permeability of the surficial hyaloclastite decreased linearly with mean effective stress, as pores and cracks closed due to elastic (recoverable) compaction up to 22-24 MPa (equivalent to ~1.3 km depth in the reservoir). Beyond this mean effective stress, denoted as P∗, we observed accelerated porosity and permeability reduction with increasing confinement, as the rock underwent permanent inelastic compaction. In comparison, the porosity and permeability of the subsurface core samples were less sensitive to mean effective stress, decreasing linearly with increasing confinement as the samples compacted elastically within the conditions tested (to 40 MPa). Although the surficial material underwent permanent, destructive compaction, it maintained higher porosity and permeability than the subsurface hyaloclastites throughout the experiments. We constrained the evolution of yield curves of the hyaloclastites, subjected to different effective mean stresses in a triaxial press. Surficial hyaloclastites underwent a brittle-ductile transition at an effective mean stress of ~10.5 MPa, and peak strength (differential stress) reached 13 MPa. When loaded to effective mean stresses of 33 and 40 MPa, the rocks compacted, producing new yield curves with a brittle-ductile transition at ~12.5 and ~19 MPa, respectively, but showed limited strength increase. In comparison, the subsurface samples were found to be much stronger, displaying higher strengths and brittle-ductile transitions at higher effective mean stresses (i.e., 37.5 MPa for 70 m sample, >75 MPa for 556 m, and 68.5 MPa for 732 m) that correspond to their lower porosities and permeabilities. Thus, we conclude that compaction upon burial alone is insufficient to explain the physical and mechanical properties of the subsurface hyaloclastites present in the reservoir at Krafla volcano. Mineralogical alteration, quantified using SEM-EDS, is invoked to explain the further reduction of porosity and increase in strength of the hyaloclastite in the active geothermal system at Krafla.

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2

Bonali, Fabio Luca, Alessandro Tibaldi, Noemi Corti, Luca Fallati, and Elena Russo. "Reconstruction of Late Pleistocene-Holocene Deformation through Massive Data Collection at Krafla Rift (NE Iceland) Owing to Drone-Based Structure-from-Motion Photogrammetry." Applied Sciences 10, no. 19 (2020): 6759. http://dx.doi.org/10.3390/app10196759.

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In the present work, we demonstrate how drone surveys coupled with structure-from-motion (SfM) photogrammetry can help to collect huge amounts of very detailed data even in rough terrains where logistics can affect classical field surveys. The area of study is located in the NW part of the Krafla Fissure Swarm (NE Iceland), a volcanotectonic rift composed of eruptive centres, extension fractures, and normal faults. The surveyed sector is characterized by the presence of a hyaloclastite ridge composed of deposits dated, on a stratigraphic basis, to the Weichselian High Glacial (29.1–12.1 ka BP), and a series of lava flows mostly dating back to 11–12 ka BP. The integration of remotely sensed surveys and field inspections enabled us to recognize that this segment of the Krafla rift is made of grabens arranged en-échelon with a left-stepping geometry. A major graben increases in width in correspondence of the hyaloclastite cone; we interpret this geometry as resulting from the mechanical contrast between the stiffer lava succession and the softer hyaloclastites, which favours the development of concentric faults. We also measured a total extension of 16.6 m and 11.2 m along the fractures affecting the lava units, and a total extension in the hyaloclastites of 29.3 m. This produces an extension rate of 1.4 mm/yr in the Holocene lavas and 1.7 ± 0.7 mm/yr in the Weichselian hyaloclastite deposits. The spreading direction we obtained for this area is N97.7° E, resulting from the av. of 568 opening direction values.

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3

Safina, Nataliya P., Irina Yu Melekestseva, Nuriya R. Ayupova, et al. "Authigenesis at the Urals Massive Sulfide Deposits: Insight from Pyrite Nodules Hosted in Ore Diagenites." Minerals 10, no. 2 (2020): 193. http://dx.doi.org/10.3390/min10020193.

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The pyrite nodules from ore diagenites of the Urals massive sulfide deposits associated with various background sedimentary rocks are studied using optical and electron microscopy and LA-ICP-MS analysis. The nodules are found in sulfide–black shale, sulfide–carbonate–hyaloclastite, and sulfide–serpentinite diagenites of the Saf’yanovskoe, Talgan, and Dergamysh deposits, respectively. The nodules consist of the core made up of early diagenetic fine-crystalline (grained) pyrite and the rim (±intermediate zone) composed of late diagenetic coarse-crystalline pyrite. The nodules are replaced by authigenic sphalerite, chalcopyrite, galena, and fahlores (Saf’yanovskoe), sphalerite, chalcopyrite and galena (Talgan), and pyrrhotite and chalcopyrite (Dergamysh). They exhibit specific accessory mineral assemblages with dominant galena and fahlores, various tellurides and Co–Ni sulfoarsenides in sulfide-black shale, sulfide–hyaloclastite–carbonate, and sulfide-serpentinite diagenites, respectively. The core of nodules is enriched in trace elements in contrast to the rim. The nodules from sulfide–black shale diagenites are enriched in most trace elements due to their effective sorption by associated organic-rich sediments. The nodules from sulfide–carbonate–hyaloclastite diagenites are rich in elements sourced from seawater, hyaloclastites and copper–zinc ore clasts. The nodules from sulfide–serpentinite diagenites are rich in Co and Ni, which are typical trace elements of ultramafic rocks and primary ores from the deposit.

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4

Cousins, Claire R., John L. Smellie, Adrian P. Jones, and Ian A. Crawford. "A comparative study of endolithic microborings in basaltic lavas from a transitional subglacial–marine environment." International Journal of Astrobiology 8, no. 1 (2009): 37–49. http://dx.doi.org/10.1017/s1473550408004369.

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AbstractSubglacially erupted Neogene basaltic hyaloclastites in lava-fed deltas in Antarctica were found to contain putative endolithic microborings preserved in fresh glass along hydrous alteration boundaries. The location and existence over the past 6 Ma of these lava deltas has exposed them to successive interglacials and subsequent percolation of the hyaloclastite with marine water. A statistical study of the hyaloclastites has found that endolithic microborings are distinctly more abundant within samples that show evidence for marine alteration, compared with those that have remained in a strictly freshwater (glacial) environment. Additionally, correlation between elevation and the abundance of microborings shows endolithic activity to be more prolific within lower elevation samples, where the hyaloclastites were influenced by marine fluids. Our study strongly suggests that endolithic microborings form more readily in marine-influenced, rather than freshwater environments. Indeed, marine fluids may be a necessary precondition for the microbial activity responsible. Thus, we suggest that the chemistry and origin of alteration fluids are controlling factors on the formation of endolithic microborings in basaltic glass. The study also contributes to the understanding of how endolithic microborings could be used as a biosignature on Mars, where basaltic lavas and aqueous alteration are known to have existed in the past.

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5

Anderson, L. D., G. E. Bebout, M. R. M. Izawa, N. J. Bridge, and N. R. Banerjee. "Chemical alteration and preservation of sedimentary/organic nitrogen isotope signatures in a 2.7 Ga seafloor volcanic sequence." International Journal of Astrobiology 18, no. 3 (2017): 235–50. http://dx.doi.org/10.1017/s1473550417000441.

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AbstractMassive to lobate volcanic flows and brecciated hyaloclastite units in the Abitibi greenstone belt allow investigation of Late Archæan seafloor alteration and associated incorporation into these rocks of nitrogen (N) biogeochemical signatures. In this suite (the Blake River Group), hyaloclastite units containing putative microbial ichnofossils are particularly enriched in large-ion lithophile elements (K, Rb, Ba, Cs), B, and Li, consistent with their having experienced the greatest fluid–rock interaction during subseafloor hydrothermal alteration. Similarly, silicate-δ18O and δ15N values for samples from the hyaloclastites show the greatest shifts from plausible magmatic values. The chemical and isotopic patterns in these tholeiitic igneous rocks greatly resemble those in modern altered seafloor basalts, consistent with the preservation of an Archæan seafloor alteration signature. The N enrichments and shifts in δ15N appear to reflect stabilization of illite and interaction with fluids carrying sedimentary/organic signatures. Enrichments of N (and the δ15N of this N) in altered glass volcanic rocks on Earth's modern and ancient seafloor point to the potential utility of N for tracing past and present biogeochemical processes in similar rocks at/near the Mars surface.

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6

Weaver, Josh, Guðjón H. Eggertsson, James E. P. Utley, et al. "Thermal Liability of Hyaloclastite in the Krafla Geothermal Reservoir, Iceland: The Impact of Phyllosilicates on Permeability and Rock Strength." Geofluids 2020 (July 14, 2020): 1–20. http://dx.doi.org/10.1155/2020/9057193.

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Geothermal fields are prone to temperature fluctuations from natural hydrothermal activity, anthropogenic drilling practices, and magmatic intrusions. These fluctuations may elicit a response from the rocks in terms of their mineralogical, physical (i.e., porosity and permeability), and mechanical properties. Hyaloclastites are a highly variable volcaniclastic rock predominantly formed of glass clasts that are produced during nonexplosive quench-induced fragmentation, in both subaqueous and subglacial eruptive environments. They are common in high-latitude geothermal fields as both weak, highly permeable reservoir rocks and compacted impermeable cap rocks. Basaltic glass is altered through interactions with external water into a clay-dominated matrix, termed palagonite, which acts to cement the bulk rock. The abundant, hydrous phyllosilicate minerals within the palagonite can dehydrate at elevated temperatures, potentially resulting in thermal liability of the bulk rock. Using surficial samples collected from Krafla, northeast Iceland, and a range of petrographic, mineralogical, and mechanical analyses, we find that smectite dehydration occurs at temperatures commonly experienced within geothermal fields. Dehydration events at 130, 185, and 600°C result in progressive mass loss and contraction. This evolution results in a positive correlation between treatment temperature, porosity gain, and permeability increase. Gas permeability measured at 1 MPa confining pressure shows a 3-fold increase following thermal treatment at 600°C. Furthermore, strength measurements show that brittle failure is dependent on porosity and therefore the degree of thermal treatment. Following thermal treatment at 600°C, the indirect tensile strength, uniaxial compressive strength, and triaxial compressive strength (at 5 MPa confining pressure) decrease by up to 68% (1.1 MPa), 63% (7.3 MPa), and 25% (7.9 MPa), respectively. These results are compared with hyaloclastite taken from several depths within the Krafla reservoir, through which the palagonite transitions from smectite- to chlorite-dominated. We discuss how temperature-induced changes to the geomechanical properties of hyaloclastite may impact fluid flow in hydrothermal reservoirs and consider the potential implications for hyaloclastite-hosted intrusions. Ultimately, we show that phyllosilicate-bearing rocks are susceptible to temperature fluctuations in geothermal fields.

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7

Fenton, Cassandra R., Robert H. Webb, and Thure E. Cerling. "Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA." Quaternary Research 65, no. 02 (2006): 324–35. http://dx.doi.org/10.1016/j.yqres.2005.09.006.

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AbstractThe failure of a lava dam 165,000 yr ago produced the largest known flood on the Colorado River in Grand Canyon. The Hyaloclastite Dam was up to 366 m high, and geochemical evidence linked this structure to outburst-flood deposits that occurred for 32 km downstream. Using the Hyaloclastite outburst-flood deposits as paleostage indicators, we used dam-failure and unsteady flow modeling to estimate a peak discharge and flow hydrograph. Failure of the Hyaloclastite Dam released a maximum 11 × 109 m3 of water in 31 h. Peak discharges, estimated from uncertainty in channel geometry, dam height, and hydraulic characteristics, ranged from 2.3 to 5.3 × 105 m3 s−1 for the Hyaloclastite outburst flood. This discharge is an order of magnitude greater than the largest known discharge on the Colorado River (1.4 × 104 m3 s−1) and the largest peak discharge resulting from failure of a constructed dam in the USA (6.5 × 104 m3 s−1). Moreover, the Hyaloclastite outburst flood is the oldest documented Quaternary flood and one of the largest to have occurred in the continental USA. The peak discharge for this flood ranks in the top 30 floods (>105 m3 s−1) known worldwide and in the top ten largest floods in North America.

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8

Watton, T. J., D. A. Jerram, T. Thordarson, and R. J. Davies. "Three-dimensional lithofacies variations in hyaloclastite deposits." Journal of Volcanology and Geothermal Research 250 (January 2013): 19–33. http://dx.doi.org/10.1016/j.jvolgeores.2012.10.011.

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9

Goguitchaichvili, Avto, Michel Prévot, Jean-Marie Dautria, and Maria Bacia. "Thermodetrital and crystallodetrital magnetization in an Icelandic hyaloclastite." Journal of Geophysical Research: Solid Earth 104, B12 (1999): 29219–38. http://dx.doi.org/10.1029/1999jb900260.

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10

Laier, Troels. "Hydrocarbon gases in Palaeogene volcanic rocks from the Lopra-1/1A well, Faroe Islands." Geological Survey of Denmark and Greenland (GEUS) Bulletin 9 (May 31, 2006): 79–90. http://dx.doi.org/10.34194/geusb.v9.4861.

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Hydrocarbon gases were monitored in the drilling fluid during deepening of the Lopra-1 well from 2178–3565 m, in which thermogenic, methane-rich gases had been found previously. The mud gas concentration, up to 105 ppm of methane, was generally higher in the hyaloclastite sequence, 2470 m – terminal depth (TD), than in the overlying lavas of the lower basalt formation. The highest concentrations of mud gas in the lower basalt formation were associated with the more porous tuffaceous zones, whereas no simple relationship could be established between measured mud gas concentrations and porosity of the hyaloclastic rocks, which showed less marked porosity variations than the lavas. Chemical (C2+ < 1%) and isotopic (δ13C1: –34 to –39‰) compositions of seven samples of mud gas collected at peak gas concentrations between 2657 m and 3442 m compare well with those of the hydrocarbon gases which had been seeping more or less continuously into the existing well since 1983, suggesting a common origin of the gases. Headspace methane concentrations measured in 135 canned samples of cuttings were scattered between 10 ppm and 6 × 103 ppm, with the exception of six samples from a short interval, 2685– 2745 m, which showed consistently high values > 104 ppm. No particularly gas-rich zones were indicated, however, by the mud gas, nor was any significant change in lithology noted for this interval. It is possible that the technique of turbo-drilling, that had been attempted over a short interval, 2657– 2675 m prior to collection of the high-level methane samples, may have caused enhanced degassing due to the very fine cuttings produced. Chemical and isotopic composition of headspace gas and mud gas indicated the same type of gas throughout the well, although headspace methane tended to be more enriched with respect to the 13C isotope. The origin of the Lopra-1 gas is discussed in the light of recent information obtained from source rock studies of central East Greenland and the Faroe–Shetland Basin.

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11

JERRAM, DOUGAL A., RICHARD T. SINGLE, RICHARD W. HOBBS, and CATHERINE E. NELSON. "Understanding the offshore flood basalt sequence using onshore volcanic facies analogues: an example from the Faroe–Shetland basin." Geological Magazine 146, no. 3 (2009): 353–67. http://dx.doi.org/10.1017/s0016756809005974.

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AbstractFlood basalts in associated volcanic rifted margins, such as the North Atlantic Igneous Province, have a significant component of lavas which are preserved in the present day in an offshore setting. A close inspection of the internal facies architecture of flood basalts onshore provides a framework to interpret the offshore sequences imaged by remote techniques such as reflection seismology. A geological interpretation of the offshore lava sequences in the Faroe–Shetland Basin, using constraints from onshore analogues such as the Faroe Islands, allows for the identification of a series of lava sequences which have characteristic properties so that they can be grouped. These are tabular simple flows, compound-braided flows, and sub-aqueously deposited hyaloclastite facies. The succession of volcanic rocks calculated in this study has a maximum thickness in excess of 6800 m. Down to the top of the sub-volcanic sediments, the offshore volcanic succession has a thickness of about 2700 m where it can be clearly identified across much of the area, with a further 2700 m or more of volcanic rock estimated from the combined gravity and seismic modelling to the north and west of the region. A large palaeo-waterbody is identified on the basis of a hyaloclastite front/apron consisting of a series of clinoforms prograding towards the eastern part of the basin. This body was > 500 m deep, must have been present at the onset of volcanism into this region, and parts of the water body would have been present during the continued stages of volcanism as indicated by the distribution of the hyaloclastite apron.

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12

Ylagan, Robert F., Stephen P. Altaner, and Antonio Pozzuoli. "Hydrothermal alteration of a rhyolitic hyaloclastite from Ponza Island, Italy." Journal of Volcanology and Geothermal Research 74, no. 3-4 (1996): 215–31. http://dx.doi.org/10.1016/s0377-0273(96)00046-7.

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13

Kurchavov, A. M., and T. N. Kheraskova. "Features of sedimentation and volcanism of the Tastauskaya rift structure in Central Kazakhstan." LITHOSPHERE (Russia) 19, no. 6 (2020): 889–901. http://dx.doi.org/10.24930/1681-9004-2019-19-6-889-901.

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Research subject. A meridional Tastau rift structure located in the Famenian sub-latitude rift system of Central Kazakhstan was investigated, including the specific features of its constituent sediments and volcanism, as well as the stages of its development.Materials and methods. The study was based on data collected during a long period of fieldwork, including a detailed study of the sequence of sedimentation processes, large-scale geocarting, sampling for various types of precision analyses.Results. The typomorphic features of the main rock types were determined. It was shown that basaltoid rocks occurred in the form of pillow structures with a hyaloclastite matrix between the pillows. Siliceous shales are saturated with thin ash silicic acid material. A geological scheme of the Tastau structure and its specific features was presented in a series of cross-sections. The developmental stages of this structure were established. The structure was referred to the rift type.Conclusion. The material and structural features of the investigated Tastau section are shown to be typical of the entire rift system of Central Kazakhstan. The pre-rift (Frasnian) stage is characterized by continental volcanism in the form of highpotassium and ultra-potassium rhyolite ignimbrites composing an encialic island-arc structure. These volcanites belong to the shoshonite and high-potassium lime-alkaline petrochemical series. The rift stage itself began in the Early Famenian age with the formation of a system of narrow deep troughs, into which the sea from the neighbouring Zhongaro-Balkhash sea region started to ingress. The conglomerates are characterized by thin flattened isometric pebbles, whose well-polished surface is similar to that of pebbles in modern sea beaches. The sandstones exhibit a high level of lamination and are characterized by poorly pelletized clastic material. The clastic material is represented by the underlying Frasnian rhyolitic ignimbrites carried in from the sides of the trough. The mature rift stage is characterized by the accumulation (under marine conditions) of pillow basalts and hyaloclastites and thin-layered silicite-clay-carbonate shales with abundant ash. The postrift stage is responsible for the formation of layered limestones of the Lower Tournaisian, developed also widely beyond the specified rift trough.

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14

Souther, J. G., J. J. Clague, and R. W. Mathewes. "Nazko cone: a Quaternary volcano in the eastern Anahim Belt." Canadian Journal of Earth Sciences 24, no. 12 (1987): 2477–85. http://dx.doi.org/10.1139/e87-232.

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Nazko cone, located in central British Columbia at the eastern end of the Anahim Volcanic Belt, is the product of at least three episodes of Quaternary volcanic activity. An eroded Pleistocene subaerial flow at the base of the pile is overlain by a subglacial mound of hyaloclastite that is, in turn, partly covered by a younger composite pyroclastic cone and associated lava flows. A whole-rock K–Ar date of 0.34 ± 0.03 Ma on the oldest flow is consistent with a hotspot model for the Anahim Belt and implies absolute late Neogene motion of 2.6 cm/year for North America. The hyaloclastite mound was erupted beneath the Cordilleran Ice Sheet during the Late Pleistocene, perhaps during the Fraser Glaciation (25 000 – 10 000 years BP). Radiocarbon dates from peat above and below Nazko tephra in a bog near the cone suggest that the volcano last erupted about 7200 years BP.Nazko basalt has 10–15% normative nepheline and is classified as basanite. This is significantly more undersaturated than basalts farther west in the Anahim Belt and may indicate an eastward shift toward a deeper or less depleted mantle source.

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15

Jarosch, Alexander, Magnus T. Gudmundsson, Thórdís Högnadóttir, and Gudni Axelsson. "Progressive cooling of the hyaloclastite ridge at Gjálp, Iceland, 1996–2005." Journal of Volcanology and Geothermal Research 170, no. 3-4 (2008): 218–29. http://dx.doi.org/10.1016/j.jvolgeores.2007.10.012.

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16

Sigvaldason, Gudmundur E. "Recent hydrothermal explosion craters in an old hyaloclastite flow, central Iceland." Journal of Volcanology and Geothermal Research 54, no. 1-2 (1992): 53–63. http://dx.doi.org/10.1016/0377-0273(92)90114-s.

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17

McGarvie, D. W., J. A. Stevenson, R. Burgess, H. Tuffen, and A. G. Tindle. "Volcano–ice interactions at Prestahnúkur, Iceland: rhyolite eruption during the last interglacial–glacial transition." Annals of Glaciology 45 (2007): 38–47. http://dx.doi.org/10.3189/172756407782282453.

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AbstractPrestahnúkur is a 570m high rhyolite glaciovolcanic edifice in Iceland’s Western Rift Zone with a volume of 0.6 km3. Uniform whole rock, mineral and glass compositions suggest that Prestahnúkur was constructed during the eruption of one magma batch. Ar-Ar dating gives an age of 89± 24 ka, which implies eruption during the transition (Oxygen Isotope substages 5d to 5a) between the Eemian interglacial and the Weichselian glacial period. Prestahnu´kur is unique among published accounts of rhyolite tuyas because a base of magmatically-fragmented tephra appears to be absent. Instead, basal exposures consist of glassy lava lobes and coarse hyaloclastite, above which are single and multiple lava sheets with matrix-supported basal breccias and hyaloclastite upper carapaces. Steepening ramp structures at sheet termini are interpreted as ice-contact features. Interactions between erupting magma and water/ice have affected all lithologies. A preliminary model for the construction of Prestahnúkur involves an effusive subglacial eruption between 2–19 years duration which never became emergent, into an ice sheet over 700m thick. If 700m of ice had built up during this interglacial–glacial transition, this would corroborate models arguing for the swift accumulation of land-based ice in rapid response to global cooling.

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18

Abrahamsen, Niels, and Regin Waagstein. "Magnetic logs from the Lopra-1/1A and Vestmanna-1 wells, Faroe Islands." Geological Survey of Denmark and Greenland (GEUS) Bulletin 9 (May 31, 2006): 41–49. http://dx.doi.org/10.34194/geusb.v9.4857.

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Susceptibility measurements from cores (representing basalt, lapilli-tuffs and tuffs) and magnetic logs from the Lopra-1/1A well are presented. The basalts fall into high- and low-susceptibility groups with no overlap. The high-susceptibility basalts (seven cores) have susceptibilities between 4 and 88 ×10–3 SI and consist of basalt with < 1% vesicles from thick massive units. The low-susceptibility basalts are intergranular, intersertal or hypocrystalline and contain no or very little (< 1%) visible magnetite, are generally more altered than the high-susceptibility basalts and have susceptibilities in the range from 0.6 to 1.4 × 10–3 SI (seven cores). The susceptibility of ten volcaniclastites of lapilli-tuff or tuff varies from 0.4 to 3.8 × 10–3 SI. The cores from the Lopra-1/1A well reveal a bimodal distribution of magnetic susceptibility. Low susceptibilities ranging from 0.4 to 4 are characteristic of altered basalts poor in magnetite, lapilli-tuffs and tuffs. Thus single measurements of susceptibility are of little use in discriminating between these three types of rock. Susceptibility logs from the Lopra-1/1A well show that the variation below 3315 m distinguishes clearly between volcaniclastics (hyaloclastites) with low and fairly constant susceptibility and basalt beds of between 5 and 10 m thickness (with high susceptibility). The volcaniclastics comprise some 60–70% of the sequence between 3315 and 3515 m with the maximum continuous sediment layer being 80 m thick. A 1½ m core of solid basalt at 2381 m and sidewall cores of basalt from the Lopra1/1A well have a mean susceptibility of 22.1 ± 3.5 × 10–3 SI (standard deviation (σ) = 23.6, number of samples (N) = 46), while samples of hyaloclastite (lapilli-tuff and tuff) have a mean susceptibility of 0.85 × 10–3 SI (σ = 0.39, N = 17). The mean values of the rock magnetic parameters for 303 basalt plugs from the Vestmanna-1 well are: Qave = 13.3 ± 0.6 (σ = 11), Save = 11.8 ± 0.6 × 10–3 SI (σ = 11) and Jave = 4.64 ± 0.25 A/m (σ = 4.4). The reversely polarised, lowermost (hidden) part of the c. 4½ km thick lower basalt formation correlates with Chron C26r. The upper (exposed) part of the lower basalt formation correlates with Chrons C26n, C25r and C25n and the more than 2.3 km thick middle and upper basalt formations correlate with Chron C24n.3r.

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19

Ayupova, N. R., V. V. Maslennikov, and K. A. Filippova. "REE geochemistry and mineralogy of ores from the Talgan Cu-Zn massive sulfide deposit, South Urals." Доклады Академии наук 487, no. 6 (2019): 659–62. http://dx.doi.org/10.31857/s0869-56524876659-662.

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The high REE contents (57,23-561,2 ppm) of thin-layered sulfide ores of the Talgan Cu-Zn massive sulfide deposit (South Urals) are related to the presence of REE minerals: galgenbergite, parisite, bastnesite, synchysite and xenotime, which were found for the first time in massive sulfide deposits of the Urals. These minerals occur in quartz-carbonate-chlorite matrix of sulfide layers, as well as pyrite nodules and sub- and euderal crystals. The chondrite-normalized REE patterns are enriched in LREEs relatively to HREEs and the presence of weak negative cerium and positive europium anomalies. The LREE contents decrease by an order of magnitude and the LREE and HREE contents become similar with decreasing amount of hyaloclastic material in sulfide layers. The REEs for the formation of REE minerals are derived from mixed carbonate-hyaloclastic and ore material during the formation of layered sulfide ores.

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20

Jeong, Gi Young, and Young Kwan Sohn. "Mineralogy and Microtextures of Basaltic Glass Alteration in Hyaloclastite, Jeju Island, Korea." Journal of Analytical Science & Technology 2, no. 1 (2011): 13–22. http://dx.doi.org/10.5355/jast.2011.13.

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Jeong, Gi Young, and Young Kwan Sohn. "Mineralogy and Microtextures of Basaltic Glass Alteration in Hyaloclastite, Jeju Island, Korea." Journal of Analytical Science & Technology 2, no. 1 (2011): 177–86. http://dx.doi.org/10.5355/jast.2011.177.

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22

Watton, Tim J., Kirstie A. Wright, Dougal A. Jerram, and Richard J. Brown. "The petrophysical and petrographical properties of hyaloclastite deposits: Implications for petroleum exploration." AAPG Bulletin 98, no. 3 (2014): 449–63. http://dx.doi.org/10.1306/08141313029.

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23

Ross, Pierre-Simon, Jean Goutier, Patrick Mercier-Langevin, and Benoît Dubé. "Basaltic to andesitic volcaniclastic rocks in the Blake River Group, Abitibi Greenstone Belt: 1. Mode of emplacement in three areas1This article is a companion paper to Ross et al. 2011. Basaltic to andesitic volcaniclastic rocks in the Blake River Group, Abitibi Greenstone Belt: 2. Origin, geochemistry, and geochronology. Canadian Journal of Earth Sciences, 48: this issue.2MRNF Contribution BEGQ 8439-2010/2011-1. Natural Resources Canada, Earth Science Sector Contribution 20100253." Canadian Journal of Earth Sciences 48, no. 4 (2011): 728–56. http://dx.doi.org/10.1139/e10-090.

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The Archean Blake River Group (BRG) of Ontario and Quebec is dominated by submarine mafic to intermediate lavas, with more restricted felsic volcanic rocks. Given the good quality of outcrop, and high level of preservation of some BRG rocks, the mafic to intermediate lavas were used in the 1970s and 1980s to better understand the evolution of massive and pillowed submarine flows, and their associated fragmental facies (pillow breccias, hyaloclastite). Potentially, the BRG could also represent a useful volcanic succession for the study of explosive submarine eruption products in the ancient record. Before this is possible, however, a regional inventory of the mafic to intermediate volcaniclastic units is needed to clarify their characteristics and origins. In this paper, we compare and contrast volcaniclastic rocks from three areas within the same formation of the northern BRG in Quebec: the Monsabrais area, the Lac Duparquet area, and the D’Alembert tuff area. Close examination reveals pronounced differences in terms of lateral continuity, thickness, grading, bedding, clast shapes, textures, etc. in the volcaniclastic rocks. These differences are interpreted to reflect vastly different emplacement processes, ranging from hyaloclastite generation as a result of self-fragmentation and lava contact with water (dominant in the Monsabrais and Lac Duparquet areas) to aqueous density currents likely fed directly by explosive submarine eruptions (dominant in the D’Alembert tuff).

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Neuffer, Daniel P., Richard A. Schultz, and Robert J. Watters. "Mechanisms of slope failure on Pyramid Mountain, a subglacial volcano in Wells Gray Provincial Park, British Columbia." Canadian Journal of Earth Sciences 43, no. 2 (2006): 147–55. http://dx.doi.org/10.1139/e05-100.

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Pyramid Mountain is a subglacial volcano in Wells Gray Provincial Park in east-central British Columbia. Landslides deform the north and east flanks of the volcano. Field strength testing and rock mass classification designate the hyaloclastite breccia in which the landslides originated as a weak, massive rock mass: uniaxial compressive strengths (UCS) range from 24 to 35 MPa, and geologic strength index (GSI) and rock mass rating (RMR) values are 6070. The shear strength of fracture surfaces in the hyaloclastite breccia, as measured by laboratory direct shear tests, can be characterized by a friction angle ϕ of 18° and cohesion c of 0.110.66 MPa. Limit-equilibrium slope stability analyses show that the landslides were probably triggered by the rapid drawdown of a surrounding englacial lake with no seismic ground acceleration required. Slope measurements and slope stability modeling indicate that Pyramid Mountain was asymmetric prior to failure: the north and east flanks had slope angles of 35°40°, and the south and west flanks had slope angles of 21°33°. Slope asymmetry may result from closer ice confinement on up-gradient (north and east) flanks due to higher ice flux in this direction relative to down-gradient (south and west) flanks. At the time of failure, the volcanic edifice was at least partially lithified, with cohesive strengths of 0.190.52 MPa. Failures of lithified subglacial and subaqueous volcanic edifices may be triggered by rapid drawdown of surrounding water without seismic loading.

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25

Crovisier, J. L., and V. Daux. "Populations of clays formed by alteration of subglacial hyaloclastites from Iceland." Chemical Geology 84, no. 1-4 (1990): 261–63. http://dx.doi.org/10.1016/0009-2541(90)90232-v.

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26

Smith, Terri L., and Rodey Batiza. "New field and laboratory evidence for the origin of hyaloclastite flows on seamount summits." Bulletin of Volcanology 51, no. 2 (1989): 96–114. http://dx.doi.org/10.1007/bf01081979.

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27

Bergh, Steffen G., and Gudmundur E. Sigvaldason. "Pleistocene mass-flow deposits of basaltic hyaloclastite on a shallow submarine shelf, South Iceland." Bulletin of Volcanology 53, no. 8 (1991): 597–611. http://dx.doi.org/10.1007/bf00493688.

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28

Zierenberg, R. A., P. Schiffman, I. R. Jonasson, R. Tosdal, W. Pickthorn, and J. McClain. "Alteration of basalt hyaloclastite at the off-axis Sea Cliff hydrothermal field, Gorda Ridge." Chemical Geology 126, no. 2 (1995): 77–99. http://dx.doi.org/10.1016/0009-2541(95)00111-2.

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29

Kňažková, M., F. Hrbáček, J. Kavan, and D. Nývlt. "Effect of hyaloclastite breccia boulders on meso-scale periglacial-aeolian landsystem in semi-arid Antarctic environment, James Ross Island, Antarctic Peninsula." Cuadernos de Investigación Geográfica 46, no. 1 (2020): 7–31. http://dx.doi.org/10.18172/cig.3800.

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In this study we aim to describe the processes leading to the creation of a specific periglacial and aeolian landsystem, which evolves around the hyaloclastite breccia boulders on James Ross Island, north-eastern Antarctic Peninsula. These boulders were deposited as a result of the Late Holocene advance of Whisky Glacier, forming a well-developed boulder train approximately 5-km long, stretching from Whisky Glacier moraine to Brandy Bay. The combination of ground temperature monitoring, snow cover measurements, grain size analysis and field survey were used to quantify and understand the interplay of periglacial and aeolian processes leading to the formation of the specific meso-scale landsystem around the boulders. The ground temperature probes were installed during January 2017 in the vicinity of two selected boulders. The two study sites, at Monolith Lake (large boulder) and Keller Stream (smaller boulder), were also fitted with snow stakes and trail cameras. An automatic weather station (AWS) on the Abernethy Flats, located approximately two kilometres to the north-west, was used as a reference site for ground temperature and snow cover thickness. The hyaloclastite breccia boulders act as obstacles to wind and trap wind-blown snow, resulting in the formation of snow accumulations on their windward and lee sides. These accumulations affect ground thermal regime and lead to the transport of fine particles by meltwater from the snow during the summer season. The snow cover also traps wind-blown fine sand resulting in the formation of fine-grained rims on the windward and lee sides of the boulders after the snow has melted. Furthermore, the meltwater affects ground moisture content, creating favourable, but spatially limited conditions for colonisation by mosses and lichens.

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30

Wilding, Martin, Donald Dingwell, Rodey Batiza, and Lionel Wilson. "Cooling rates of hyaloclastites: applications of relaxation geospeedometry to undersea volcanic deposits." Bulletin of Volcanology 61, no. 8 (2000): 527–36. http://dx.doi.org/10.1007/s004450050003.

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31

Yamagishi, Hiromitsu, and Kazuo Shimura. "Giant rockfalls of Neogene hyaloclastite crushing the 2nd Shiraito- tunnel in Shimamaki Town, Hokkaido, Japan." Journal of the Geological Society of Japan 103, no. 10 (1997): XXXIII—XXXIV. http://dx.doi.org/10.5575/geosoc.103.xxxiii.

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32

Aalto, K. R. "Depositional Sequence of Argillite, Diamictite, Hyaloclastite, and Lava Flows within the Franciscan Complex, Northern California." Journal of Geology 94, no. 5 (1986): 744–52. http://dx.doi.org/10.1086/629079.

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33

Porreca, M., F. Cifelli, C. Soriano, et al. "Hyaloclastite fragmentation below the glass transition: An example from El Barronal submarine volcanic complex (Spain)." Geology 42, no. 1 (2014): 87–90. http://dx.doi.org/10.1130/g34744.1.

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34

Hald, N., and J. G. Larsen. "Early Tertiary, low-potassium tholeiites from exploration wells on the West Greenland shelf." Rapport Grønlands Geologiske Undersøgelse 136 (December 31, 1987): 1–25. http://dx.doi.org/10.34194/rapggu.v136.8008.

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Data on the Tertiary basalts in the Davis Strait region are reported from two exploration wells drilled by Arco and Mobil on the West Greenland shelf. Hellefisk 1 (67°53 'N, 56°44'W), situated only 60 km east of the mid-line in Davis Strait, penetrated the upper 690 m of a subaeriallava sequence continuous with the onshore volcanics of Disko and situated beneath 2.3 km of Paleocene to Quaternary sediments. The lavas are feldspar microporphyritic tholeiites and mostly unmetamorphosed despite the presence of laumontite and prehnite in the vesicular top zones. Nukik 2 (65°38'N, 54°46'W) penetrated 150 m of hyaloclastites and tholeiitic olivine dolerite sheets, presumably sills, some 200 km further to the south. These vo1canics are also deeply buried and are of unknown extension. The drilled rocks, except for the much altered hyaloclastites in the Nukik 2 well, have low contents of Ti02 (0.99-2.03%), K2O (0.09-0.18%) and P2O5 (0.08-0.21%), La/Sm ratios less than one and 87Sr/86Sr ratios of 0.7032 to 0.7044. Chemically they are related to the MORB-like picrites of Baffin Island rather than the less depleted tholeiites of West Greenland. In both areas the MORB affinity may be related to eruptions through a strongly attenuated lithosphere associated with the opening of Baffin Bay and Davis Strait.

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35

Frolova, Yu V. "Patterns of transformations in the compositions and properties of Icelandic hyaloclastites during lithogenesis." Moscow University Geology Bulletin 65, no. 2 (2010): 104–14. http://dx.doi.org/10.3103/s0145875210020067.

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36

Watton, T. J., D. A. Jerram, T. Thordarson, and R. J. Davies. "Corrigendum to “Three-dimensional lithofacies variations in hyaloclastite deposits” [J. Volcanol. Geotherm. Res. 250 (2013) 19–33]." Journal of Volcanology and Geothermal Research 250 (January 2013): 155–56. http://dx.doi.org/10.1016/j.jvolgeores.2012.12.010.

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37

Altaner, Stephen P., Robert F. Ylagan, Samuel M. Savin, James L. Aronson, Harvey E. Belkin, and Antonio Pozzuoli. "Geothermometry, geochronology, and mass transfer associated with hydrothermal alteration of a rhyolitic hyaloclastite from Ponza Island, Italy." Geochimica et Cosmochimica Acta 67, no. 2 (2003): 275–88. http://dx.doi.org/10.1016/s0016-7037(02)01077-3.

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38

Schopka, Herdís H., Magnús T. Gudmundsson, and Hugh Tuffen. "The formation of Helgafell, southwest Iceland, a monogenetic subglacial hyaloclastite ridge: Sedimentology, hydrology and volcano–ice interaction." Journal of Volcanology and Geothermal Research 152, no. 3-4 (2006): 359–77. http://dx.doi.org/10.1016/j.jvolgeores.2005.11.010.

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39

Bauluz, Blanca, Donald R. Peacor, and Robert F. Ylagan. "Transmission Electron Microscopy Study of Smectite Illitization During Hydrothermal Alteration of a Rhyolitic Hyaloclastite from Ponza, Italy." Clays and Clay Minerals 50, no. 2 (2002): 157–73. http://dx.doi.org/10.1346/000986002760832766.

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40

van Otterloo, Jozua, Ray A. F. Cas, and Ceinwen R. Scutter. "The fracture behaviour of volcanic glass and relevance to quench fragmentation during formation of hyaloclastite and phreatomagmatism." Earth-Science Reviews 151 (December 2015): 79–116. http://dx.doi.org/10.1016/j.earscirev.2015.10.003.

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41

MONTAGUE, K. E., A. W. WALTON, and S. T. HASIOTIS. "EUENDOLITHIC MICROBORINGS IN BASALT GLASS FRAGMENTS IN HYALOCLASTITES: EXTENDING THE ICHNOFABRIC INDEX TO MICROBIOEROSION." PALAIOS 25, no. 6 (2010): 393–99. http://dx.doi.org/10.2110/palo.2009.p09-025r.

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42

Kurokawa, Akira. "Formation of felsic pumiceous hyaloclastites: a case study from Tadami district, Fukushima Prefecture, Japan." JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY 86, no. 10 (1991): 439–58. http://dx.doi.org/10.2465/ganko.86.439.

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43

Nichols, A. R. L., M. Potuzak, and D. B. Dingwell. "Cooling rates of basaltic hyaloclastites and pillow lava glasses from the HSDP2 drill core." Geochimica et Cosmochimica Acta 73, no. 4 (2009): 1052–66. http://dx.doi.org/10.1016/j.gca.2008.11.023.

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44

Yamada, Tomomi, and Yoshiyuki Okano. "A Volcanic Reservoir: Integrated Facies Distribution Modeling and History Matching of a Complex Pressure System." SPE Reservoir Evaluation & Engineering 10, no. 01 (2007): 77–85. http://dx.doi.org/10.2118/93159-pa.

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Summary A Tcf-class gas field has been producing over several decades in Japan. The reservoir body comprises stacked rhyolite lava domes erupted in a submarine environment. A porous network developed in each dome and rapid chilling on contact with seawater caused hyaloclastite to be deposited over it. Although hyaloclastite is also porous in this field, its permeability has been reduced dramatically by the presence of clay minerals. Impermeable basaltic sheets and mudstone seams are also present. Each facies plays a specific role in the pressure system. Stratigraphic correlation originally identified multiple reservoirs. Gas has been produced almost exclusively from the largest one. However, following 10 to 20 years of production, the pressures within unexploited reservoirs were noticed to have declined at a variety of rates. Unusual localized behavior has also been observed. Because seismic data were not proved particularly informative, we decided to remodel the entire system by specifically using pressure data. We employed a combination of multipoint geostatistics and probability perturbation theories. This approach successfully captured the curved facies boundaries within stacked lava domes while accounting for pressure data by means of history matching to address nonstationarity in the real field. Building a suitable training image is commonly a difficult aspect of multipoint methods and poses particular problems for volcanic reservoirs. It was accomplished here by iteratively adjusting the prototype until satisfactory history matching was achieved with a reasonable number of perturbations. Ambiguous reservoir boundaries were represented stochastically by populating a predetermined model space with pay and nonpay pixels. The modeling results closely simulate measured pressure histories and appear realistic in terms of both facies distributions and reservoir boundaries. They suggest that uneven pressure declines between different units are caused by the tortuous flow channels that connect them. The results also account for the unusual smaller-scale pressure performances observed. The final training image obtained here indicates more intensive spatial variations in facies than previously appreciated. Original gas in place (OGIP) estimates made with 20 equiprobable realizations are scattered within ±15% of the mean value. Estimates of incremental recovery made by drilling a step-out well reveal greater variation than those made by installing a booster compressor, which quantifies a higher associated geological risk.

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45

Walton, Anthony W., and Peter Schiffman. "Alteration of hyaloclastites in the HSDP 2 Phase 1 Drill Core 1. Description and paragenesis." Geochemistry, Geophysics, Geosystems 4, no. 5 (2003): n/a. http://dx.doi.org/10.1029/2002gc000368.

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46

Valdrè, Giovanni. "An improved low-power-consumption heating stage for X-ray powder diffraction." Journal of Applied Crystallography 32, no. 3 (1999): 543–45. http://dx.doi.org/10.1107/s0021889899000990.

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An improved low-power-consumption easy-to-operate simple heating stage for use in connection with an X-ray powder diffractometer is described and discussed. No modification is required to the conventional specimen chamber, which can be used safely up to a specimen temperature of at least 1200 K with a temperature accuracy of a few degrees. The stage is interchangeable with conventional specimen holders, without the need for realignment of the diffractometer. To prevent specimen oxidation, provisions are made for heating in an inert gaseous environment. Also, care has been taken to prevent scattered radiation escaping from the specimen chamber. The stage allows the study of structural transformations with temperature and so far it has been used successfully for the characterization of very different materials, such as hyaloclastite, smectites, montmorillonites and chlorocadmates with perovskite-like structures. Although the device has been designed for the Philips PW1820 X-ray diffractometer, it can be applied to other types of X-ray diffractometer.

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47

Breheny, C., K. R. Moore, A. Costanzo, and M. Feely. "Reconstruction of an Ordovician seafloor volcanohydrothermal system: a case study from the Copper Coast, southeastern Ireland using field, geochemical and fluid inclusion data." Mineralogical Magazine 80, no. 1 (2016): 157–74. http://dx.doi.org/10.1180/minmag.2015.079.7.09.

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AbstractVolcanic rocks in south County Waterford include flow-top hyaloclastite, pillow lavas and peperite, which are formed typically by sub-aqueous eruption or intrusion into unconsolidated sediment. Element mobility in wet sediment during emplacement of volcanic intrusions was reconstructed on a variety of spatial scales using bulk-rock and mineral analysis. Magma-sediment and magma-water interactions enhanced hydrothermal alteration. The chemistry of chlorite was a function of mixing between an Fe-rich magmatic fluid and a Mg-rich meteoric fluid. Chlorite geothermometry yields temperatures of formation between 230 and 388°C compatible with other metamorphic indicators. Fluid inclusion microthermometric data from genetically-related mineralized quartz veins reveal a hydrothermal vein mineralization event that occurred at lower temperatures during the end stage of volcanic activity. A convection driven mixing trend reflects the trapping of co-existing brine with entrained seawater concomitant with, the late stages of emplacement of the Bunmahon Volcano intrusions.

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48

Emeleus, C. H. "The Tertiary lavas and sediments of northwest Rhum, Inner Hebrides." Geological Magazine 122, no. 5 (1985): 419–37. http://dx.doi.org/10.1017/s0016756800035342.

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AbstractSeveral small outliers of Tertiary lavas and sediments rest with strong unconformity on a buried landscape eroded from Torridonian sediments and Tertiary granophyre. Erosion continued during the period of sediment and lava accumulation. Four formations are recognized; these are, in order of increasing age, the Orval Formation (hawaiite and basaltic hawaiite lavas), the Guirdil Formation (icelandite lavas, interbedded conglomerates), the Upper Fionchra Formation (tholeiitic basaltic andesite lavas, hyaloclastite deposits, basal conglomerate) and the Lower Fionchra Formation (alkali and transitional basalt, basaltic hawaiite and hawaiite lava flows, basal conglomerate); each is separated by an erosional interval. Clasts in the conglomerates reveal a history of erosion of a terrain exposing gneisses, Torridonian sediments, igneous rocks derived from the Rhum Tertiary Central Complex (including allivalites), and Tertiary lavas of local origin but also including, in the oldest conglomerates, tholeiitic basalts not now preserved on or near Rhum. Prior to and during lava and sediment accumulation, erosion on Rhum had cut down to a level similar to that of the present day, although not to the extent that high-grade thermally altered rocks, which are a marked feature of the Central Complex, were being eroded in any quantity. A sequence of east–west trending valleys, possibly initiated on the line of the earlier Main Ring Fault, drained the area of the Central Complex which then, as now, must have been high ground. Small lakes occasionally formed in the valleys allowing the accumulation of fine-grained sediment with plant remains, and promoting the formation of hyaloclastite deposits when buried by later flows. No source for any of the lava formations is preserved on Rhum; they are thought to have come from feeders north of Rhum, possibly near Canna, and to have ponded against the hills and valleys near and in the Central Complex.The oldest tholeiitic lavas, not now found in situ, were followed by alkali and transitional flows compositionally similar to the Skye Main Lava Series but characteristically feldsparphyric; the most mafic also contain phenocrysts of magnesian olivine (with included Cr-Al-rich spinels) and aluminous spinel. Both the early alkalic/transitional basalts and the youngest hawaiites and basaltic hawaiites equilibrated at pressures < 9 kb; the tholeiitic basaltic andesites and icelandites equilibrated at relatively shallows depths.Apart from a few N–S to NW–SE-trending basalt dykes, the lava formations represent the youngest Tertiary igneous event on Rhum.

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49

Porreca, M., F. Cifelli, C. Soriano, G. Giordano, and M. Mattei. "Magma flow within dykes in submarine hyaloclastite environments: an AMS study of the Miocene Cabo de Gata volcanic units." Geological Society, London, Special Publications 396, no. 1 (2014): 133–57. http://dx.doi.org/10.1144/sp396.14.

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50

Gudmundsson, M. T., F. Pálsson, H. Björnsson, and ℋ. Högnadóttir. "The hyaloclastite ridge formed in the subglacial 1996 eruption in Gjálp, Vatnajökull, Iceland: present day shape and future preservation." Geological Society, London, Special Publications 202, no. 1 (2002): 319–35. http://dx.doi.org/10.1144/gsl.sp.2002.202.01.16.

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