Journal articles: 'Seamount volcano'

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Smellie, John L. "Chapter 3.2a Bransfield Strait and James Ross Island: volcanology." Geological Society, London, Memoirs 55, no. 1 (2021): 227–84. http://dx.doi.org/10.1144/m55-2018-58.

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AbstractFollowing more than 25 years of exploration and research since the last regional appraisal, the number of known subaerially exposed volcanoes in the northern Antarctic Peninsula region has more than trebled, from less than 15 to more than 50, and that total must be increased at least three-fold if seamounts in Bransfield Strait are included. Several volcanoes remain unvisited and there are relatively few detailed studies. The region includes Deception Island, the most prolific active volcano in Antarctica, and Mount Haddington, the largest volcano in Antarctica. The tectonic environment of the volcanism is more variable than elsewhere in Antarctica. Most of the volcanism is related to subduction. It includes very young ensialic marginal basin volcanism (Bransfield Strait), back-arc alkaline volcanism (James Ross Island Volcanic Group) and slab-window-related volcanism (seamount offshore of Anvers Island), as well as volcanism of uncertain origin (Anvers and Brabant islands; small volcanic centres on Livingston and Greenwich islands). Only ‘normal’ arc volcanism is not clearly represented, possibly because active subduction virtually ceased atc.4 Ma. The eruptive environment for the volcanism varied between subglacial, marine and subaerial but a subglacial setting is prominent, particularly in the James Ross Island Volcanic Group.

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Buff, L., M. G. Jackson, K. Konrad, J. G. Konter, M. Bizimis, A. Price, E. F. Rose-Koga, J. Blusztajn, A. A. P. Koppers, and Santiago Herrera. "“Missing links” for the long-lived Macdonald and Arago hotspots, South Pacific Ocean." Geology 49, no. 5 (January 12, 2021): 541–44. http://dx.doi.org/10.1130/g48276.1.

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Abstract The Cook-Austral volcanic lineament extends from Macdonald Seamount (east) to Aitutaki Island (west) in the South Pacific Ocean and consists of hotspot-related volcanic islands, seamounts, and atolls. The Cook-Austral volcanic lineament has been characterized as multiple overlapping, age-progressive hotspot tracks generated by at least two mantle plumes, including the Arago and Macdonald plumes, which have fed volcano construction for ∼20 m.y. The Arago and Macdonald hotspot tracks are argued to have been active for at least 70 m.y. and to extend northwest of the Cook-Austral volcanic lineament into the Cretaceous-aged Tuvalu-Gilbert and Tokelau Island chains, respectively. Large gaps in sampling exist along the predicted hotspot tracks, complicating efforts seeking to show that the Arago and Macdonald hotspots have been continuous, long-lived sources of hotspot volcanism back into the Cretaceous. We present new major- and trace-element concentrations and radiogenic isotopes for three seamounts (Moki, Malulu, Dino) and one atoll (Rose), and new clinopyroxene 40Ar/39Ar ages for Rose (24.81 ± 1.02 Ma) and Moki (44.53 ± 10.05 Ma). All volcanoes are located in the poorly sampled region between the younger Cook-Austral and the older, Cretaceous portions of the Arago and Macdonald hotspot tracks. Absolute plate motion modeling indicates that the Rose and Moki volcanoes lie on or near the reconstructed traces of the Arago and Macdonald hotspots, respectively, and the 40Ar/39Ar ages for Rose and Moki align with the predicted age progression for the Arago (Rose) and Macdonald (Moki) hotspots, thereby linking the younger Cook-Austral and older Cretaceous portions of the long-lived (>70 m.y.) Arago and Macdonald hotspot tracks.

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Mikhailik, Pavel, Evgenii Mikhailik, and Vladimir Ivanov. "Gold in Ferromanganese Deposits from the NW Pacific." Minerals 11, no. 9 (September 8, 2021): 979. http://dx.doi.org/10.3390/min11090979.

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Ferromanganese crusts from four different areas of the North-West Pacific Ocean—the Detroit (northern part of the Imperial Ridge) guyot, the Zubov (Marshall Islands) guyot, the “Gummi Bear” seamount (an intraplate volcano near the Krusenstern FZ), and Belyaevsky volcano (the Sea of Japan)—were studied. Samples from the Detroit and Zubov guyots and the “Gummi Bear” seamount have similar chemical and mineral compositions of hydrogenetic cobalt-rich ferromanganese crusts. Crust from the Sea of Japan seems to reflect a hydrothermal influence. The gold content in most samples from the Detroit guyot was 68 ppb and from the Zubov guyot varied from 180 to 1390 ppb, which is higher than the average for the Pacific crusts (55 ppb). Gold content in two other samples was less than 10 ppb. Based on the electron microscopic studies, aggregation of gold particles with a size of 680 μm were identified in the Detroit guyot crust. The sizes of the Au particles are up to 10–15 μm, which has not been previously noted. Gold particles similar in morphology and size were also found in the Zubov guyot crust, which is located far from the Detroit guyot. The largest particle of gold (≈60 μm), represented by electrum, was found in the clay substrate from the “Gummi Bear” seamount. The lamellar, rudaceous morphology of the gold particles from the Detroit and Zubov guyots reflects their in situ formation, in contrast to the agglutinated, rounded with traces of dragging gold grain found in the substrate of the sample from the “Gummi Bear” seamount. Three-component (Ag-Au-Cu) gold particles were found in the hydrothermal crust from the Belyaevsky underwater volcano. Grains similar in composition were also found in Co-rich crust. The research results show that the gold was probably added to by hydrothermal fluid in the already-formed hydrogenetic ferromanganese crusts during rejuvenated volcanic stages. Biogeochemical processes may have played a major role in the formation of submicron solid-phase gold particles.

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Rodrigo, Cristian, Jenny M. Blamey, Oliver Huhn, and Christine Provost. "Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?" Andean Geology 45, no. 3 (June 6, 2018): 344. http://dx.doi.org/10.5027/andgeov45n3-3086.

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The rifting zone of Bransfield Strait, Antarctica, is tectonically and geologically unique. It is a back-arc basin that was opened by extensional forces associated to roll-back subduction after cessation of spreading activity of the Phoenix Ridge, and the transtension of the westward ending of Scotia-Antarctica Plate boundary. The Bransfield Rift/Ridge is still active generating volcanism or magma rise to force hydrothermal activity. During the ANT-XXV/4 cruise onboard R/V “Polarstern”, standard CTD and beam transmission measurements were done to determine temperature anomaly and turbidity. Water sampling was performed to determine δ3He and to find thermophilic microorganisms to examine the Orca seamount hydrothermal activity. A temperature anomaly of ~0.08 °C, a pick of turbidity, and high value of δ3He (>10%) were found inside Orca seamount. Results are consistent with a hydrothermal flux coming from the seamount. The report of the first observation of thermophilic and hyperthermophilic microorganisms in cold deep Antarctic waters is part of this study. Inside Orca seamount these microorganisms were found at three different depth levels close to the bottom. We suggest that the fluid migration from the volcano resulted from recent magmatic activity and provided the required elemental nutrients for microbial growth. Besides some thermophiles were found outside the seamount in a small quantity close to the seafloor. These would probably be related to subsidiary structures of the Orca seamount, or were transported by currents from other active volcanic sites as Deception Island. The finding of these thermophilic and hyperthermophilic microorganisms raise questions about the dispersal and their resistance in these extreme environments.

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5

Melekestsev, I. V. "New type of volcano-tectonic structure - 42-km wide deep-water calderoida at underwater Detroit Seamount Highland (North-Western Pacific)." Доклады Академии наук 489, no. 4 (December 10, 2019): 384–87. http://dx.doi.org/10.31857/s0869-56524894384-387.

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At the northern part of Emperor Seamount Chain we discovered and classified the previously unknown rounded volcano-tectonic 42-km deep-sea morphostructure as calderoida (authors terminology). It lies at -2900-2200 m depth and represents very complex structure being broken by faults into many blocks of different sizes and shapes. It is situated at the northern portion of the Detroit Seamount Rise (NW Pacific Ocean) which is a Pliocene horst. The calderoida was formed in the Early Pleistocene at depths from -3000 to -2000 m. Its analogues have not been found on Earth yet.

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Carbotte, Suzanne M., Adrien Arnulf, Marc Spiegelman, Michelle Lee, Alistair Harding, Graham Kent, Juan Pablo Canales, and Mladen Nedimović. "Stacked sills forming a deep melt-mush feeder conduit beneath Axial Seamount." Geology 48, no. 7 (April 27, 2020): 693–97. http://dx.doi.org/10.1130/g47223.1.

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Abstract Magmatic systems are composed of melt accumulations and crystal mush that evolve with melt transport, contributing to igneous processes, volcano dynamics, and eruption triggering. Geophysical studies of active volcanoes have revealed details of shallow-level melt reservoirs, but little is known about fine-scale melt distribution at deeper levels dominated by crystal mush. Here, we present new seismic reflection images from Axial Seamount, northeastern Pacific Ocean, revealing a 3–5-km-wide conduit of vertically stacked melt lenses, with near-regular spacing of 300–450 m extending into the inferred mush zone of the mid-to-lower crust. This column of lenses underlies the shallowest melt-rich portion of the upper-crustal magma reservoir, where three dike intrusion and eruption events initiated. The pipe-like zone is similar in geometry and depth extent to the volcano inflation source modeled from geodetic records, and we infer that melt ascent by porous flow focused within the melt lens conduit led to the inflation-triggered eruptions. The multiple near-horizontal lenses are interpreted as melt-rich layers formed via mush compaction, an interpretation supported by one-dimensional numerical models of porous flow in a viscoelastic matrix.

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7

Lavelle, J. W., E. T. Baker, and G. A. Cannon. "Ocean currents at Axial Volcano, a northeastern Pacific seamount." Journal of Geophysical Research: Oceans 108, no. C2 (February 2003): n/a. http://dx.doi.org/10.1029/2002jc001305.

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8

Moretti, Sacha, Apostolos Salmatonidis, Xavier Querol, Antonella Tassone, Virginia Andreoli, Mariantonia Bencardino, Nicola Pirrone, Francesca Sprovieri, and Attilio Naccarato. "Contribution of Volcanic and Fumarolic Emission to the Aerosol in Marine Atmosphere in the Central Mediterranean Sea: Results from Med-Oceanor 2017 Cruise Campaign." Atmosphere 11, no. 2 (January 30, 2020): 149. http://dx.doi.org/10.3390/atmos11020149.

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This work studied the contribution of the geogenic sources volcanoes and fumaroles to the aerosol in marine atmosphere in the central Mediterranean basin. For this purpose, in the framework of the Med-Oceanor measurement program, we carried out a cruise campaign in the summer of 2017 to investigate the impact to the aerosol of the most important Mediterranean volcanoes (Mount Etna, Stromboli Island, and Marsili Seamount) and solfatara areas (Phlegraean Fields complex, Volcano Islands, Ischia Island, and Panarea submarine fumarole). We collected PM10 and PM2.5 samples in 12 sites and performed chemical characterization to gather information about the concentration of major and trace elements, elemental carbon (EC), organic carbon (OC), and ionic species. The use of triangular plots and the calculation of enrichment factors confirmed the interception of volcanic plume. We integrated the outcomes from chemical characterization with the use of factor analysis and SEM/EDX analysis for the source apportionment. Anthropogenic and natural sources including shipping emissions, volcanic and fumarolic load, as well as sea spray were identified as the main factors affecting aerosol levels in the study area. Furthermore, we performed pattern recognition analysis by stepwise linear discriminant analysis to seek differences in the composition of PM10 and PM2.5 samples according to their volcanic or solfatara origin.

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9

Sakai, Shunta, Naoto Hirano, Yildirim Dilek, Shiki Machida, Kazutaka Yasukawa, and Yasuhiro Kato. "Tokoro Belt (NE Hokkaido): an exhumed, Jurassic – Early Cretaceous seamount in the Late Cretaceous accretionary prism of northern Japan." Geological Magazine 158, no. 1 (June 24, 2019): 72–83. http://dx.doi.org/10.1017/s0016756819000633.

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AbstractThe Tokoro Belt exposed in NE Hokkaido (Japan) represents part of a Late Cretaceous accretionary complex, which includes variously metamorphosed volcanic rocks that are interbedded with chert, lenticular limestone and some fore-arc sedimentary rocks. The Tokoro Belt is notably different from other Late Cretaceous accretionary complexes around the Pacific Rim because of widespread occurrence of basalts and volcaniclastic rocks in it. The Nikoro Group, characterized by widespread occurrence of volcanic rocks, is divided into western, eastern and southern sections based on the internal structure, geochemical affinities and metamorphic grades of their volcanic lithologies. OIB (ocean island basalt)-type volcanic rocks with low-grade metamorphic overprint predominate in the western and southern sections, whereas MORB (mid-ocean ridge basalt)- and OIA (ocean island alkaline basalt)-type rocks in the eastern section with partly high-pressure metamorphism make up the northern part of the eastern section. Trace element patterns display transitional trends from MORB to OIA geochemical affinities. OIB-type rocks display trace element characteristics similar to those of shield volcano lavas on Hawaii, rather than small and mainly alkaline, Polynesian hotspot lavas; furthermore, they show significant HREE (heavy rare earth element) enrichment probably caused by plume–ridge interaction. Widespread OIBs in the Tokoro Belt represents tectonic slices of a large (>80 km wide) Hawaiian-style, seamount shield volcano on the Izanagi oceanic plate that was accreted into the continental margin of Far East Asia in the Late Cretaceous.

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10

Staudigel, H., S. R. Hart, A. Pile, B. E. Bailey, E. T. Baker, S. Brooke, D. P. Connelly, et al. "Vailulu'u Seamount, Samoa: Life and death on an active submarine volcano." Proceedings of the National Academy of Sciences 103, no. 17 (April 13, 2006): 6448–53. http://dx.doi.org/10.1073/pnas.0600830103.

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11

Weigel, Wilfried, and Ingo Grevemeyer. "The Great Meteor seamount: seismic structure of a submerged intraplate volcano." Journal of Geodynamics 28, no. 1 (August 1999): 27–40. http://dx.doi.org/10.1016/s0264-3707(98)00030-1.

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12

Robin, C., P. Colantoni, M. Gennesseaux, and J. P. Rehault. "Vavilov seamount: A mildly alkaline Quaternary volcano in the Tyrrhenian Basin." Marine Geology 78, no. 1-2 (November 1987): 125–36. http://dx.doi.org/10.1016/0025-3227(87)90071-5.

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13

Garcia, Michael O., Jackie Caplan-Auerbach, Eric H. De Carlo, M. D. Kurz, and N. Becker. "Geology, geochemistry and earthquake history of Lṑihi Seamount, Hawaìi's youngest volcano." Geochemistry 66, no. 2 (May 2006): 81–108. http://dx.doi.org/10.1016/j.chemer.2005.09.002.

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14

Connell, Laurie, Anne Barrett, Alexis Templeton, and Hubert Staudigel. "Fungal Diversity Associated with an Active Deep Sea Volcano: Vailulu'u Seamount, Samoa." Geomicrobiology Journal 26, no. 8 (November 30, 2009): 597–605. http://dx.doi.org/10.1080/01490450903316174.

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15

Karl, D. M., G. M. McMurtry, A. Malahoff, and M. O. Garcia. "Loihi Seamount, Hawaii: a mid-plate volcano with a distinctive hydrothermal system." Nature 335, no. 6190 (October 1988): 532–35. http://dx.doi.org/10.1038/335532a0.

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16

Casanova, Jean-Paul. "Chaetognaths from the Alvin dives on the Seamount Volcano 7 (east tropical Pacific)." Journal of Plankton Research 13, no. 3 (1991): 539–48. http://dx.doi.org/10.1093/plankt/13.3.539.

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17

Wheat, C. Geoffrey, Jeffrey S. Seewald, and Ken Takai. "Fluid transport and reaction processes within a serpentinite mud volcano: South Chamorro Seamount." Geochimica et Cosmochimica Acta 269 (January 2020): 413–28. http://dx.doi.org/10.1016/j.gca.2019.10.037.

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18

Karl, David M., Andrew M. Brittain, and Bronte D. Tilbrook. "Hydrothermal and microbial processes at Loihi Seamount, a mid-plate hot-spot volcano." Deep Sea Research Part A. Oceanographic Research Papers 36, no. 11 (November 1989): 1655–73. http://dx.doi.org/10.1016/0198-0149(89)90065-4.

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Cocchi, Luca, Fabio Caratori Tontini, Filippo Muccini, and Cornel E. J. de Ronde. "Magnetic Expression of Hydrothermal Systems Hosted by Submarine Calderas in Subduction Settings: Examples from the Palinuro and Brothers Volcanoes." Geosciences 11, no. 12 (December 10, 2021): 504. http://dx.doi.org/10.3390/geosciences11120504.

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Volcanism is the most widespread expression of cyclic processes of formation and/or destruction that shape the Earth’s surface. Calderas are morphological depressions resulting from the collapse of a magma chamber following large eruptions and are commonly found in subduction-related tectono-magmatic regimes, such as arc and back-arc settings. Some of the most impressive examples of seafloor hydrothermal venting occur within submarine calderas. Here, we show the results of magnetic investigations at two hydrothermally active submarine calderas, i.e., Palinuro Seamount in the Southern Tyrrhenian Sea, Italy, and Brothers volcano of the Kermadec arc, New Zealand. These volcanoes occur in different geodynamic settings but show similarities in the development of their hydrothermal systems, both of which are hosted within calderas. We present a new integrated model based on morphological, geological and magnetic data for the Palinuro caldera, and we compare this with the well-established model of Brothers caldera, highlighting the differences and common features in the geophysical expressions of both hydrothermal systems. For consistency with the results at Brothers volcano, we build a model of demagnetised areas associated with hydrothermal alteration derived from 3D inversion of magnetic data. Both these models for Brothers and Palinuro show that hydrothermal up-flow zones are strongly controlled by caldera structures which provide large-scale permeability pathways, favouring circulation of the hydrothermal fluids at depth.

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20

Johnson, H. Paul, and Robert W. Embley. "Axial seamount: An active ridge axis volcano on the Central Juan De Fuca Ridge." Journal of Geophysical Research 95, B8 (1990): 12689. http://dx.doi.org/10.1029/jb095ib08p12689.

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Koeda, Keita, Soutarou Takashima, Takehisa Yamakita, Shinji Tsuchida, and Yoshihiro Fujiwara. "Deep-Sea Fish Fauna on the Seamounts of Southern Japan with Taxonomic Notes on the Observed Species." Journal of Marine Science and Engineering 9, no. 11 (November 19, 2021): 1294. http://dx.doi.org/10.3390/jmse9111294.

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Several volcanic islands and submarine volcanoes exist in the sea connecting the Izu-Bonin Islands with the Mariana Islands, with trenches and islands formed by the submergence of the Pacific Plate under the Philippine Sea Plate. Although designated as a Marine Protected Area (MPA) in December 2020, the seamounts’ biodiversity has not been sufficiently researched. Therefore, direct observations and specimen sampling were conducted on four seamounts in this area using a remotely operated vehicle (ROV), autonomous underwater vehicle (AUV), and baited cameras (BCs). The ROV survey was conducted for 2–4 days on each seamount and divided into shallow and deep areas. During the expedition, 20 orders and 51 families of 81 deep-sea fish species were observed, including several potentially undescribed species, new genus or species records from Japanese waters, new depth records, new ecological information, and several rare fishes. The fish fauna and biodiversity abundance clearly differed among the seamounts; the seamount with a hydrothermal vent had the lowest diversity among the four seamounts. In shallow water, 23, 7, and 12 species were recorded only by ROV, AUV, and BC, respectively, indicating that combining these methods is beneficial for understanding the fish fauna of seamounts.

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Doran, Adrian K., and Wayne C. Crawford. "Continuous evolution of oceanic crustal structure following an eruption at Axial Seamount, Juan de Fuca Ridge." Geology 48, no. 5 (February 6, 2020): 452–56. http://dx.doi.org/10.1130/g46831.1.

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Abstract We present the first continuous observations of the temporal evolution of oceanic crustal shear velocity beneath Axial Seamount, a submarine volcano on the Juan de Fuca Ridge (offshore northwestern North America). Weekly values of seafloor compliance, the periodic deformation of the seafloor under ocean waves, were estimated over the time period between December 2014 and May 2018 using data from two cabled broadband ocean-bottom seismometers with collocated absolute pressure sensors. We inverted these measurements for shear-wave velocity within the volcano beneath the two stations as a function of depth and time. Our results, combined with estimates of seismic compressional wave velocity, suggest that the shallow melt reservoir and the lower crust beneath the central caldera contain melt fractions of 14% and at least 4%, respectively. The eruption of April 2015 induced a dramatic drop in shear velocities beneath the central station, primarily in the lower crust, which could have been caused by an increase in melt fraction, a change in small-scale melt geometry, or both. The absence of such a change beneath the eastern flank of the caldera indicates that there is a lower-crustal conduit beneath the caldera center, which is much narrower in cross section (<1 km2) than the overlying melt reservoir (≥42 km2). Our study demonstrates the promise of using continuous data to understand submarine volcanism and crustal accretionary processes.

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Clague, David A., Alice S. Davis, James L. Bischoff, Jacqueline E. Dixon, and Renee Geyer. "Lava bubble-wall fragments formed by submarine hydrovolcanic explosions on Lō'ihi Seamount and Kīlauea Volcano." Bulletin of Volcanology 61, no. 7 (January 13, 2000): 437–49. http://dx.doi.org/10.1007/pl00008910.

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McVey, B. G., E. E. E. Hooft, B. A. Heath, D. R. Toomey, M. Paulatto, J. V. Morgan, P. Nomikou, and C. B. Papazachos. "Magma accumulation beneath Santorini volcano, Greece, from P-wave tomography." Geology 48, no. 3 (December 9, 2019): 231–35. http://dx.doi.org/10.1130/g47127.1.

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Abstract Despite multidisciplinary evidence for crustal magma accumulation below Santorini volcano, Greece, the structure and melt content of the shallow magmatic system remain poorly constrained. We use three-dimensional (3-D) velocity models from tomographic inversions of active-source seismic P-wave travel times to identify a pronounced low-velocity anomaly (–21%) from 2.8 km to 5 km depth localized below the northern caldera basin. This anomaly is consistent with depth estimates of pre-eruptive storage and a recent inflation episode, supporting the interpretation of a shallow magma body that causes seismic attenuation and ray bending. A suite of synthetic tests shows that the geometry is well recovered while a range of melt contents (4%–13% to fully molten) are allowable. A thin mush region (2%–7% to 3%–10% melt) extends from the main magma body toward the northeast, observed as low velocities confined by tectono-magmatic lineaments. This anomaly terminates northwest of Kolumbo; little to no melt underlies the seamount from 3 to 5 km depth. These structural constraints suggest that crustal extension and edifice loads control the geometry of magma accumulation and emphasize that the shallow crust remains conducive to melt storage shortly after a caldera-forming eruption.

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Baker, Edward T., Russell E. McDuff, and Gary J. Massoth. "Hydrothermal venting from the summit of a ridge axis Seamount: Axial Volcano, Juan de Fuca Ridge." Journal of Geophysical Research 95, B8 (1990): 12843. http://dx.doi.org/10.1029/jb095ib08p12843.

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HAASE, K. M., and C. W. DEVEY. "The Petrology and Geochemistry of Vesteris Seamount, Greenland Basin--an Intraplate Alkaline Volcano of Non-Plume Origin." Journal of Petrology 35, no. 2 (April 1, 1994): 295–328. http://dx.doi.org/10.1093/petrology/35.2.295.

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Haase, K. M., M. Hartmann, and H. J. Wallrabe-Adams. "The geochemistry of ashes from Vesterisbanken Seamount, Greenland Basin: implications for the evolution of an alkaline volcano." Journal of Volcanology and Geothermal Research 70, no. 1-2 (January 1996): 1–19. http://dx.doi.org/10.1016/0377-0273(95)00059-3.

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WHEAT, C., P. FRYER, A. FISHER, S. HULME, H. JANNASCH, M. MOTTL, and K. BECKER. "Borehole observations of fluid flow from South Chamorro Seamount, an active serpentinite mud volcano in the Mariana forearc." Earth and Planetary Science Letters 267, no. 3-4 (March 30, 2008): 401–9. http://dx.doi.org/10.1016/j.epsl.2007.11.057.

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Chamov, N. P., I. E. Stukalova, S. Yu Sokolov, A. A. Peyve, N. V. Gor’kova, A. A. Razumovskiy, M. E. Bylinskaya, and L. A. Golovina. "Tectonic-sedimentary system of the Atlantis-meteor seamounts (North Atlantic): late Miocene to Pliocene volcanic and sedimentary environments and the position within the Atlantic-arctic structures." Литология и полезные ископаемые, no. 5 (October 20, 2019): 418–38. http://dx.doi.org/10.31857/s0024-497x20195418-438.

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The article concerns the original materials obtained in the 33-rd cruise of the R/V Akademik Nikolai Strakhov in the eastern part of the North Atlantic while studying the system of AtlantisMeteor seamounts. The system is a single volcanic uplift formed on the Canary Abyssal Plate, and is one of the key objects for understanding the geological history of this segment of the Atlantic Ocean. The article discusses basalts, tefrites, and organogenic-terrigenous lagoon-marine sediments dredged from the Atlantis, Plateau, and Cruiser seamounts. The petrographic properties and compositions of the basalts of the seamounts Atlantis and Cruiser reflect significant differences in the environments of their effusions. In the first case, well-crystallized, not showing signs of vesicularity, olivine basalts poured out in deep-water conditions. Glassy highly vesicular basalts from the Cruiser seamount are characteristic of shallow subaerial effusions. Evidence has been obtained in favor of the subaerial settings of the accumulation of tefrites from the Plato seamount. The regularities of lithogenetic transformations of organogenic-terrigenous deposits of the Cruiser seamount, exposed to high-temperature effects of subaerial lava flows, are revealed. In the course of volcanogenic-sedimentary lithogenesis, the lignite-like material lost its primary structure, turning into natural anisotropic coke with a wide development of fusinite and pyrofusinite. The authors of the article associate the studied volcanic manifestations with the final (Late MiocenePliocene) stage of volcanism in the seamount system, which preceded the disintegration of the system, its progressive immersion and the transformation of islands into guyots.

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Choi, Hakkyum, Seung-Sep Kim, Sung-Hyun Park, and Hyoung Jun Kim. "Geomorphological and Spatial Characteristics of Underwater Volcanoes in the Easternmost Australian-Antarctic Ridge." Remote Sensing 13, no. 5 (March 5, 2021): 997. http://dx.doi.org/10.3390/rs13050997.

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Underwater volcanoes and their linear distribution on the flanks of mid-ocean ridges are common submarine topographic structures at intermediate- and fast-spreading systems, where sufficient melt supplies are often available. Such magma sources beneath the seafloor located within a few kilometers of the corresponding ridge-axis tend to concentrate toward the axis during the upwelling process and contribute to seafloor formation. As a result, seamounts on the flanks of the ridge axis are formed at a distance from the spreading axis and distributed asymmetrically about the axis. In this study, we examined three linearly aligned seamount chains on the flanks of the KR1 ridge, which is the easternmost and longest Australian-Antarctic Ridge (AAR) segment. The AAR is an intermediate-spreading rate system located between the Southeast Indian Ridge and Macquarie Triple Junction of the Australian-Antarctic-Pacific plates. By inspecting the high-resolution shipboard multi-beam bathymetric data newly acquired in the study area, we detected 20 individual seamounts. The volcanic lineament runs parallel to the spreading direction of the KR1 segment. The geomorphologic parameters of height, basal area, volume, and summit types of the identified seamounts were individually measured. We also investigated the spatial distribution of the seamounts along the KR1 segment, which exhibits large variations in axial morphology with depth along the ridge axis. Based on the geomorphology and spatial distribution, all the KR1 seamounts can be divided into two groups: the subset seamounts of volcanic chains distributed along the KR1 segment characterized by high elevation and large volume, and the small seamounts distributed mostly on the western KR1. The differences in the volumetric magnitude of volcanic eruptions on the seafloor and the distance from the given axis between these two groups indicate the presence of magma sources with different origins.

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Vereshchaka, A. L. "New species of Galatheidae (Crustacea: Anomura: Galatheoidea) from volcanic seamounts off northern New Zealand." Journal of the Marine Biological Association of the United Kingdom 85, no. 1 (February 2005): 137–42. http://dx.doi.org/10.1017/s0025315405010957h.

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Two new species of Munida (M. gordoni and M. grieveae) and one new species of Agononida (A. nielbrucei) are described from volcanic seamounts off northern New Zealand (RV ‘Tangaroa’, National Institute of Water and Atmospheric Research [NIWA], New Zealand). Description of new species and preliminary examination of NIWA collections reveal unusually high endemism of volcanic seamount populations of Galatheidae.

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Ivanenko, Viatcheslav N., and Frank D. Ferrari. "New species ofStygiopontius(Copepoda: Siphonostomatoida: Dirivultidae) from a deep-sea hydrothermal volcano in the New Ireland Fore-Arc system (Papua New Guinea)." Journal of the Marine Biological Association of the United Kingdom 93, no. 7 (July 2, 2013): 1805–12. http://dx.doi.org/10.1017/s0025315413000763.

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A male of the new speciesStygiopontius senckenbergibelonging to the family Dirivultidae Humes & Dojiri, 1980 (Copepoda: Siphonostomatoida) and endemic to deep-sea hydrothermal vents, is described from a raised fault block structure south of Edison seamount of the New Ireland Fore-Arc system (Papua New Guinea). The copepods were collected in by box-corer during cruise SO-133 of the RV ‘Sonne’ at a depth of 1610–1625 m, 3°19′S 152°35′E. The new species belongs to a group of eight species that are separate from 21 congeners on the basis of setation of legs 1 and 4: the coxa of leg 1 has an inner seta (absent on the others) and the third exopodal segment of leg 4 has three outer spines (instead of two spines). The new species shares withS. pectinatusHumes, 1987 a pectinate maxilliped but differs from it in lacking two pectinate, terminal claw-like setae on the endopod of the antenna.

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Tsuchiya, Nobutaka, Jiro Ishii, Tetsuyoshi Yamazaki, and Kenji Shuto. "A newly discovered Quaternary volcano from northeast Japan Sea: K-Ar age of andesite dredged from the Shiribeshi Seamount." JOURNAL OF MINERALOGY, PETROLOGY AND ECONOMIC GEOLOGY 84, no. 11 (1989): 391–97. http://dx.doi.org/10.2465/ganko.84.391.

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OGAWA, MARI, AKIRA TAKEUCHI, MUTSUO HATTORI, MASAHARU OKANO, MISUMI AOKI, MAKIKO IMAMURA, TOYOKI KSUBOI, TOMONORI TSUBOI, DAISUKE TANIMOTO, and TAKESHI NAGANUMA. "Geological and microbial anomalies in the extinct submarine volcano, Shiribeshi Seamount, in the eastern margin of the Japan Sea." Island Arc 11, no. 4 (December 2002): 274–86. http://dx.doi.org/10.1046/j.1440-1738.2002.00370.x.

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Sunamura, Michinari, Yowsuke Higashi, Chiwaka Miyako, Jun-ichiro Ishibashi, and Akihiko Maruyama. "Two Bacteria Phylotypes Are Predominant in the Suiyo Seamount Hydrothermal Plume." Applied and Environmental Microbiology 70, no. 2 (February 2004): 1190–98. http://dx.doi.org/10.1128/aem.70.2.1190-1198.2004.

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ABSTRACT Microbial diversity and populations in a hydrothermal plume that was present inside the caldera of the Suiyo Seamount, a submarine volcano on the Izu-Bonin Arc, were investigated by performing a phylogenetic analysis of the 16S rRNA gene and by using fluorescence in situ hybridization (FISH). Corresponding to transmissivity, an indicator of turbidity, the vertical total cell count as determined by 4′,6′-diamidino-2-phenylindole (DAPI) staining varied from 5.6 × 104 to 1.1 × 105 cells ml−1, and the apparent plume layer was assessed to be at a depth of 1,050 to 1,200 m inside the caldera and to contain 1.0 × 105 to 1.1 × 105 cells ml−1. From microbial samples collected in the plume by an in situ filtration system, the following two major phylogenetic groups, which were closely related to sulfur-oxidizing microbes, were obtained: the SUP05 group belonging to the gamma subclass of the Proteobacteria (13 of 20 clones) and the SUP01 group belonging to the epsilon subclass of the Proteobacteria (5 of 20 clones). Specific oligonucleotide probes for these groups (SUP05-187 and SUP01-63) were designed and were used with various water samples obtained from the Suiyo Seamount. In the apparent plume layer, up to 66% of the total counts of microbial cells were estimated to be Bacteria cells that hybridized to EUB338, and few cells were identified by the archaeal probe ARCH915. Almost all Bacteria cells were hard to identify with the known group-specific probes, such as ALF19, GAM42a, and CF319, while 88 to 90% of the Bacteria cells hybridized with SUP05-187 and >98% of them were considered members of the SUP05 and SUP01 populations. In a low-temperature vent fluid emitted from a bivalve-colonized mound, the SUP05 cells accounted for >99% of the Bacteria cells, suggesting that a portion of the plume cells originated on the surface of the seafloor at a depth of about 1,380 m. From further analysis of cell morphology (i.e., cell size and cell elongation index) we inferred that the SUP05 cells were active in the plume layer at a depth of 1,050 to 1,200 m compared to the activity in a near-bottom layer, while many elongated cells were found between these layers. These findings suggest that the morphology and distribution of SUP05 cells have complex relationships with hydrothermal activities and water circulation. Although growth and production rates remain to be defined, we concluded that this Suiyo Seamount caldera has functioned as a natural continuous incubator for these two phylotypes of Bacteria in an aphotic deep-sea environment.

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Sobisevich, A. L. "THE EARLY STAGES OF FERROMANGANESE ORE GENESIS ON THE GUYOTS OF THE MAGELLAN SEAMOUNTS (THE PACIFIC OCEAN)." Geology and Mineral Resources of World Ocean 16, no. 4 (2020): 3–13. http://dx.doi.org/10.15407/gpimo2020.04.003.

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The success of recently developed geological and geophysical methods and technologies for monitoring of mud volcanoes in the Kerch-Taman region is eventually based on the fundamental scientific results accumulated at the turn of the century under the overall leadership of the Academician E.F. Shnyukov. The results of geological and geophysical studies of the Mount Karabetov mud volcano (Taman Peninsula) featuring the passive seismoacoustic sounding method are presented. New data on the spatial configuration of subvertical fluid-saturated structures associated with the volcano's feeding system were obtained. Subsequent common interpretation of the geophysical data and the results of the structural-geomorphologic observations allowed one to formulate a consistent hypothesis on the possible deep mechanism of mud volcanic activity responsible for the mostly paroxysmal nature of eruptions of the Mount Karabetov.

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Kent, Adam J. R., Marc D. Norman, Ian D. Hutcheon, and Edward M. Stolper. "Assimilation of seawater-derived components in an oceanic volcano: evidence from matrix glasses and glass inclusions from Loihi seamount, Hawaii." Chemical Geology 156, no. 1-4 (April 1999): 299–319. http://dx.doi.org/10.1016/s0009-2541(98)00188-0.

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Emerson, David, and Craig L. Moyer. "Neutrophilic Fe-Oxidizing Bacteria Are Abundant at the Loihi Seamount Hydrothermal Vents and Play a Major Role in Fe Oxide Deposition." Applied and Environmental Microbiology 68, no. 6 (June 2002): 3085–93. http://dx.doi.org/10.1128/aem.68.6.3085-3093.2002.

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ABSTRACT A number of hydrothermal vent sites exist on the summit of the Loihi Seamount, a shield volcano that is part of the Hawaiian archipelago. The vents are 1,100 to 1,325 m below the surface and range in temperature from slightly above ambient (10°C) to high temperature (167°C). The vent fluid is characterized by high concentrations of CO2 (up to 17 mM) and Fe(II) (up to 268 μM), but there is a general paucity of H2S. Most of the vents are surrounded by microbial mats that have a gelatinous texture and are heavily encrusted with rust-colored Fe oxides. Visually, the Fe oxides appeared homogeneous. However, light microscopy revealed that the oxides had different morphologies, which fell into three classes: (i) sheaths, (ii) twisted or irregular filaments, and (iii) amorphous oxides. A morphological analysis of eight different samples indicated that the amorphous oxides were overall the most abundant; however, five sites had >50% sheaths and filamentous oxides. These latter morphologies are most likely the direct result of microbial deposition. Direct cell counts revealed that all of the oxides had abundant microbial populations associated with them, from 6.9 × 107 to 5.3 × 108 cells per ml of mat material. At most sites, end point dilution series for lithotrophic Fe oxidizers were successful out to dilutions of 10−6 and 10−7. A pure culture was obtained from a 10−7 dilution tube; this strain, JV-1, was an obligate, microaerophilic Fe oxidizer that grew at 25 to 30°C. A non-cultivation-based molecular approach with terminal-restriction fragment length polymorphism also indicated the common presence of Fe-oxidizing bacteria at Loihi. Together, these results indicate that Fe-oxidizing bacteria are common at the Loihi Seamount and probably play a major role in Fe oxidation. A review of the literature suggests that microbially mediated Fe oxidation at hydrothermal vents may be important globally.

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Fryer, Patricia, C. Geoffrey Wheat, Trevor Williams, Christopher Kelley, Kevin Johnson, Jeffrey Ryan, Walter Kurz, et al. "Mariana serpentinite mud volcanism exhumes subducted seamount materials: implications for the origin of life." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2165 (January 6, 2020): 20180425. http://dx.doi.org/10.1098/rsta.2018.0425.

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The subduction of seamounts and ridge features at convergent plate boundaries plays an important role in the deformation of the overriding plate and influences geochemical cycling and associated biological processes. Active serpentinization of forearc mantle and serpentinite mud volcanism on the Mariana forearc (between the trench and active volcanic arc) provides windows on subduction processes. Here, we present (1) the first observation of an extensive exposure of an undeformed Cretaceous seamount currently being subducted at the Mariana Trench inner slope; (2) vertical deformation of the forearc region related to subduction of Pacific Plate seamounts and thickened crust; (3) recovered Ocean Drilling Program and International Ocean Discovery Program cores of serpentinite mudflows that confirm exhumation of various Pacific Plate lithologies, including subducted reef limestone; (4) petrologic, geochemical and paleontological data from the cores that show that Pacific Plate seamount exhumation covers greater spatial and temporal extents; (5) the inference that microbial communities associated with serpentinite mud volcanism may also be exhumed from the subducted plate seafloor and/or seamounts; and (6) the implications for effects of these processes with regard to evolution of life. This article is part of a discussion meeting issue ‘Serpentine in the Earth system’.

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BLAKE, JAMES A., and PATRICIA A. RAMEY-BALCI. "A new genus and species of spionid polychaete (Annelida, Spionidae) from a deep-water cold seep site in the Eastern Mediterranean Sea off Turkey." Zoosymposia 19, no. 1 (December 28, 2020): 121–34. http://dx.doi.org/10.11646/zoosymposia.19.1.14.

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A new spionid polychaete was discovered in deep-sea sediments in the eastern Mediterranean Sea during an expedition by the Ocean Exploration Trust. Specimens were collected by the E/V Nautilus in August 2012 off Turkey, at a depth of 2216 m on the Anaximander Seamount at the Amsterdam mud volcano site. Cores were taken from sediments covered with microbial mats. The new species belongs to the Pygospiopsis-Atherospio Group, which has unusual neuropodial hooks, modified neurosetae in some anterior setigers, and branchiae in middle body segments that are broad, flattened, and fused to the dorsal lamellae. The new species is assigned to a new genus and species, Aciculaspio anaximanderi n. gen., n. sp., and is unusual in having a reduced setiger 1 lacking notosetae; well-developed pre- and postsetal lamellae that encompass the neurosetae and notosetae; notopodial lamellae free from the branchiae in anterior setigers that become fused and flattened in middle and posterior segments; unidentate hooded hooks in both noto- and neuropodia; neuropodial spines in setigers 4–10; and a pygidium with three anal cirri. Aciculaspio anaximanderi n. gen., n. sp. is the first species in the Atherospio-Pygospiopsis Group collected from a deep-water cold seep habitat.

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Cousens, Brian L., R. L. Chase, and J. G. Schilling. "Geochemistry and origin of volcanic rocks from Tuzo Wilson and Bowie seamounts, northeast Pacific Ocean." Canadian Journal of Earth Sciences 22, no. 11 (November 1, 1985): 1609–17. http://dx.doi.org/10.1139/e85-170.

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The origin of the Tuzo Wilson Seamounts, 50 km south of the Queen Charlotte Islands, has been ascribed by various workers to either the Pratt–Welker mantle plume, which has formed the Pratt–Welker seamount chain, or the formation of a new segment of the Explorer–Juan de Fuca spreading ridge system. Abundances of major and trace elements in dredged alkali basalts from Tuzo Wilson and Bowie seamounts (360 km northwest of Tuzo Wilson Seamounts) are typical of alkaline volcanism on ocean islands associated with mantle plumes, but 87Sr/86Sr ratios (0.70252–0.70258) fall within the range of mid-ocean ridge basalts (MORB) from the Explorer and Juan de Fuca ridges. Geochronological and chemical data from the Pratt–Welker, Bowie, and Tuzo Wilson seamounts suggest that the Tuzo Wilson Seamounts are in an early stage of development as a result of activity of the Pratt–Welker mantle plume but that contributions from both a depleted and an undepleted mantle source are necessary to reconcile trace-element and Sr isotope values. Modelling of rare-earth behaviour during partial melting indicates that neither the Tuzo Wilson nor Bowie basalts could be generated from a mantle source similar to that of the Explorer or Juan de Fuca MORB, unless recent metasomatism has enriched the seamounts' source region in incompatible elements.

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Koski, Randolph A. "Ferromanganese deposits from the Gulf of Alaska Seamount Province: mineralogy, chemistry, and origin." Canadian Journal of Earth Sciences 25, no. 1 (January 1, 1988): 116–33. http://dx.doi.org/10.1139/e88-012.

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Ferromanganese-oxide deposits dredged from four seamounts (Welker, Miller, Murray, and Patton) in the Gulf of Alaska Seamount Province include poorly crystallized microlaminated crusts on basalt substrate, well-crystallized Mn-oxide veins in epiclastic sedimentary rocks, and crystalline Mn-oxide layers and micronodules in phosphorite. The principal rock types dredged are alkali-basalt pillow fragments and tuffaceous conglomerate and sandstone. The glassy rims of pillow fragments, the glassy goundmass of large volcanic clasts, and the tuffaceous component of the sediment are altered to palagonite. Other low-temperature alteration products include phillipsite, smectite, and carbonate-apatite.Thick (10–50 mm) Fe–Mn crusts consist mainly of δ-MnO2; straight and cuspate growth laminae indicate variable growth rates and periods of nondeposition. A larger number of detrital particles toward the top of thick crusts record the increasing influence of active volcanoes of the Aleutian arc during northwestward movement of the Pacific plate. Thick crusts on basalt substrate have higher Mn/Fe ratios and lower Co content than Fe–Mn crusts from low-latitude seamounts of the central Pacific region. Thin (< 10 mm) crusts on volcaniclastic substrate contain todorokite and birnessite and have higher Mn/Fe ratios, Ni, and Cu and lower Fe and Co than thick Gulf of Alaska crusts.Veins of todorokite and cryptomelane with complex internal structure occur in altered tuffaceous sandstone and conglomerate from Miller Seamount. Fibrous todorokite has a composition similar to those of other marine examples but may contain up to 7% Mn2+ in M2 sites. Microprobe analysis of the marine cryptomelane indicates a composition that is approximately (K,Ba)1–2(Mn4+,Co)7–8O16∙x(H2O).A third type of Fe–Mn deposit in phosphorite is an intimate mixture of todorokite (and minor δ-MnO2)-bearing layers and micronodules, carbonate-apatite, and phillipsite that encloses grains of altered volcanic glass and lithic fragments.The microlaminated structure, mineralogy (predominantly δ-MnO2), and composition (Mn/Fe ratio and transition metal, rare earth element, U, and Th contents) of the thick crusts are characteristic of hydrogenetic Fe–Mn crusts elsewhere in the Pacific. Conversely, the crystallinity and chemical composition of the Mn-oxide veins and thin crusts indicate formation during diagenesis of the volcanogenic sediment substrate. Mn and other transition metals are mobilized during low-temperature oxidative alteration (palagonitization) of basaltic volcanic glass; the oxidation of Fe2+ to Fe3+ during palagonitization and the dissolution of the dilute biogenic fraction of the sediment combine to lower the Eh of ambient pore fluid and enhance the mobility of Mn2+. Diagenesis in the phosphatic sandstone from Patton Seamount involves organic-rich sediment and pore waters elevated in phosphorus owing to upwelling above a large volcanic edifice.

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Nomikou, Paraskevi, Christian Hübscher, and Steven Carey. "The Christiana–Santorini–Kolumbo Volcanic Field." Elements 15, no. 3 (June 1, 2019): 171–76. http://dx.doi.org/10.2138/gselements.15.3.171.

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The Christiana–Santorini–Kolumbo volcanic field in the South Aegean Sea (Greece) is one of the most important in Europe, having produced more than 100 explosive eruptions in the last 400,000 years. Its volcanic centers include the extinct Christiana Volcano and associated seamounts, Santorini caldera with its intracaldera Kameni Volcano, Kolumbo Volcano, and 24 other submarine cones of the Kolumbo chain. Earthquakes, volcanic eruptions, submarine mass wasting, neotectonics and gas releases from these centers pose significant geohazards to human populations and infrastructures of the Eastern Mediterranean region. Defining the geological processes and structures that contribute to these geohazards will provide an important framework to guide future monitoring and research activities aimed at hazard mitigation.

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Seton, Maria, Simon Williams, Nick Mortimer, Sebastien Meffre, Steven Micklethwaite, and Sabin Zahirovic. "Magma production along the Lord Howe Seamount Chain, northern Zealandia." Geological Magazine 156, no. 9 (January 18, 2019): 1605–17. http://dx.doi.org/10.1017/s0016756818000912.

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AbstractOne of the world’s most notable intraplate volcanic regions lies on the eastern Australian plate and includes two age-progressive trails offshore (Tasmantid and Lord Howe seamount chains) and the world’s longest continental hotspot trail (Cosgrove Track). While most studies agree that these chains formed by the rapid northward motion of the Australian plate over a slowly moving mantle source, the volcanic output along these trails, their plate–mantle interactions and the source of the magmatism remain unconstrained. A geophysical mapping and dredging campaign on the RV Southern Surveyor (ss2012_v06) confirmed the prolongation of the Lord Howe Seamount Chain to the South Rennell Trough, ∼200 km further north than previously sampled. Radiometric dating of these new samples at 27–28 Ma, together with previously published results from the southern part of the chain, indicate straightforward northward motion of the Australian plate over a quasi-stationary hotspot as predicted by Indo-Atlantic and Pacific hotspot models. A peak in Lord Howe Seamount Chain magmatism in late Oligocene time, also seen in the Tasmantid and Cosgrove trails, matches a 27–23 Ma slowdown of Australian plate motion. The average magma flux of the Lord Howe hotspot is estimated at 0.4 m3 s−1, similar to rates of crustal production at the South Rennell Trough prior to cessation of spreading in middle Oligocene time, supporting a potential genetic relationship to this spreading system. In addition, plate tectonic modelling suggests that the seamounts and plateaus in the Coral Sea may host the earliest evidence of plume activity in the area.

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Koppers, A. A. P., T. Yamazaki, and J. Geldmacher. "IODP Expedition 330: Drilling the Louisville Seamount Trail in the SW Pacific." Scientific Drilling 15 (March 1, 2013): 11–22. http://dx.doi.org/10.5194/sd-15-11-2013.

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Deep-Earth convection can be understood by studying hotspot volcanoes that form where mantle plumes rise up and intersect the lithosphere, the Earth's rigid outer layer. Hotspots characteristically leave age-progressive trails of volcanoes and seamounts on top of oceanic lithosphere, which in turn allow us to decipher the motion of these plates relative to "fixed" deep-mantle plumes, and their (isotope) geochemistry provides insights into the long-term evolution of mantle source regions. However, it is strongly suggested that the Hawaiian mantle plume moved ~15° south between 80 and 50 million years ago. This raises a fundamental question about other hotspot systems in the Pacific, whether or not their mantle plumes experienced a similar amount and direction of motion. Integrated Ocean Drilling Program (IODP) Expedition 330 to the Louisville Seamounts showed that the Louisville hotspot in the South Pacific behaved in a different manner, as its mantle plume remained more or less fixed around 48°S latitude during that same time period. Our findings demonstrate that the Pacific hotspots move independently and that their trajectories may be controlled by differences in subduction zone geometry. Additionally, shipboard geochemistry data shows that, in contrast to Hawaiian volcanoes, the construction of the Louisville Seamounts doesn’t involve a shield-building phase dominated by tholeiitic lavas, and trace elements confirm the rather homogenous nature of the Louisville mantle source. Both observations set Louisville apart from the Hawaiian-Emperor seamount trail, whereby the latter has been erupting abundant tholeiites (characteristically up to 95% in volume) and which exhibit a large variability in (isotope) geochemistry and their mantle source components. <br><br> doi:<a href="http://dx.doi.org/10.2204/iodp.sd.15.02.2013" target="_blank">10.2204/iodp.sd.15.02.2013</a>

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Seoane, Lucía, Guillaume Ramillien, Benjamin Beirens, José Darrozes, Didier Rouxel, Thierry Schmitt, Corinne Salaün, and Frédéric Frappart. "Regional Seafloor Topography by Extended Kalman Filtering of Marine Gravity Data without Ship-Track Information." Remote Sensing 14, no. 1 (December 31, 2021): 169. http://dx.doi.org/10.3390/rs14010169.

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An iterative Extended Kalman Filter (EKF) approach is proposed to recover a regional set of topographic heights composing an undersea volcanic mount by the successive combination of large numbers of gravity measurements at sea surface using altimetry satellite-derived grids and taking the error uncertainties into account. The integration of the non-linear Newtonian operators versus the radial and angular distances (and its first derivatives) enables the estimation process to accelerate and requires only few iterations, instead of summing Legendre polynomial series or using noise-degraded 2D-FFT decomposition. To show the effectiveness of the EKF approach, we apply it to the real case of the bathymetry around the Great Meteor seamount in the Atlantic Ocean by combining only geoid height/free-air anomaly datasets and using ship-track soundings as reference for validation. Topography of the Great Meteor seamounts structures are well-reconstructed, especially when regional compensation is considered. Best solution gives a RMS equal to 400 m with respect to the single beam depth observations and it is comparable to RMS obtained for ETOPO1 of about 365 m. Larger discrepancies are located in the seamount flanks due to missing high-resolution information for gradients. This approach can improve the knowledge of seafloor topography in regions where few echo-sounder measurements are available.

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Ferrer, Oriol, Oscar Gratacós, Eduard Roca, and Josep Anton Muñoz. "Modeling the interaction between presalt seamounts and gravitational failure in salt-bearing passive margins: The Messinian case in the northwestern Mediterranean Basin." Interpretation 5, no. 1 (February 1, 2017): SD99—SD117. http://dx.doi.org/10.1190/int-2016-0096.1.

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The northwest Mediterranean Basin includes a thick Messinian salt sequence composed of three evaporitic units. From these, the intermediate unit, which is dominantly composed of halite, acted as a gravitational detachment favoring the downslope failure of the overlying sediments in a thin-skinned deformation regime. As a result, the structure of the margin is characterized by an upper extensional domain with basinward-dipping listric normal faults and a lower contractional domain that accommodates upslope extension by folding, salt inflation, or diapir squeezing. Lower to middle Miocene volcanic seamounts (presalt reliefs) located at the upper extensional domain locally disrupted the evaporitic units and produced salt flow perturbations. They acted as passive buttresses during the gravitational failure modifying the structural zonation of the margin. Using an experimental approach (sandbox models), we analyze the role played by seamounts during the kinematic evolution of passive margins and how they alter salt flow and suprasalt deformation during gravitational gliding. The experiments found that the seamounts locally interrupt the structural zonation of the margin because they hindered downdip salt flow during early deformation. Seamounts initially compartmentalize the margin architecture, resulting in the development of two gravitational subsystems with two extensional/contractional pairs that are subsequently reconnected when the accumulation of salt analog upslope of the relief is enough to overthrust it. From this point onward, the cover is passively translated downslope as a regional system. The changes in the viscous layer flow velocity related to the dip differences between the flanks and edges of the seamount determine the kinematic evolution of this system. Our experiments also provide geometric constraints to consider during interpretation of these structures, which are commonly poorly imaged in seismic data.

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Davis, Earl. "Volcanic action at Axial Seamount." Nature 403, no. 6768 (January 2000): 379–80. http://dx.doi.org/10.1038/35000335.

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Smellie, John L., and Adam P. Martin. "Chapter 5.2a Erebus Volcanic Province: volcanology." Geological Society, London, Memoirs 55, no. 1 (2021): 415–46. http://dx.doi.org/10.1144/m55-2018-62.

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AbstractThe Erebus Volcanic Province is the largest Neogene volcanic province in Antarctica, extendingc.450 km north–south and 170 km wide east–west. It is dominated by large central volcanoes, principally Mount Erebus, Mount Bird, Mount Terror, Mount Discovery and Mount Morning, which have sunk more than 2 km into underlying sedimentary strata. Small submarine volcanoes are also common, as islands and seamounts in the Ross Sea (Terror Rift), and there are many mafic scoria cones (Southern Local Suite) in the Royal Society Range foothills and Dry Valleys. The age of the volcanism ranges betweenc.19 Ma and present but most of the volcanism is <5 Ma. It includes active volcanism at Mount Erebus, with its permanent phonolite lava lake. The volcanism is basanite–phonolite/trachyte in composition and there are several alkaline petrological lineages. Many of the volcanoes are pristine, predominantly formed of subaerially erupted products. Conversely, two volcanoes have been deeply eroded. That at Minna Hook is mainly glaciovolcanic, with a record of the ambient mid–late Miocene eruptive environmental conditions. By contrast, Mason Spur is largely composed of pyroclastic density current deposits, which accumulated in a large mid-Miocene caldera that is now partly exhumed.

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Syedin, V. T., S. P. Pletnev, and T. E. Sedysheva. "VOLCANIC COMPLEXES AND TECTON-MAGMATIC STAGES OF THE EVOLUTION OF THE MAGELLAN SEAMOUNTS (PACIFIC OCEAN). MESSAGE 1: VOLCANIC COMPLEXES." Bulletin of Kamchatka Regional Association «Educational-Scientific Center». Earth Sciences, no. 5(56) (December 26, 2022): 90–116. http://dx.doi.org/10.31431/1816-5524-2022-4-56-90-116.

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The paper presents original and published data of radioisotope dating of volcanic rocks of the Magellan Seamounts. These data and available geological materials allow us to distinguish five major volcanic complexes of different ages in the guyots of the Magellan Seamounts: 1 — Late Jurassic-Early Cretaceous (earliest Cretaceous); 2 — Early Cretaceous (Apt-Albian); 3 — Late Cretaceous (Late Cenomanian-Turonian- Early Campanian); 4 — Late Cretaceous (Late Campanian-Maastrichian); 5 — Cenozoic. Each of these age complexes corresponds to a specific tectonic-magmatic stage of the evolution of the Magellan Seamounts and characterizes a specific geomorphological space (pedestal, main body, small complicating superimposed structures of the second order). This division is based on numerous isotopic age determinations for 11 guyots obtained by K-Ar and Ar-Ar methods. The tectonic-magmatic evolutionary stages of the Magellan Seamounts correspond, in general, to the periods of tectonic activation for other structures of the Pacific Ocean bed.

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Journal articles on the topic 'Seamount volcano'

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