The Official Magazine of The

Total Page:16

File Type:pdf, Size:1020Kb

The Official Magazine of The OceTHE OFFICIALa MAGAZINEn ogOF THE OCEANOGRAPHYra SOCIETYphy CITATION Phillips, B.T., M. Dunbabin, B. Henning, C. Howell, A. DeCiccio, A. Flinders, K.A. Kelley, J.J. Scott, S. Albert, S. Carey, R. Tsadok, and A. Grinham. 2016. Exploring the “Sharkcano”: Biogeochemical observations of the Kavachi submarine volcano (Solomon Islands). Oceanography 29(4):160–169, https://doi.org/10.5670/ oceanog.2016.85. DOI https://doi.org/10.5670/oceanog.2016.85 COPYRIGHT This article has been published in Oceanography, Volume 29, Number 4, a quarterly journal of The Oceanography Society. Copyright 2016 by The Oceanography Society. All rights reserved. USAGE Permission is granted to copy this article for use in teaching and research. Republication, systematic reproduction, or collective redistribution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The Oceanography Society. Send all correspondence to: [email protected] or The Oceanography Society, PO Box 1931, Rockville, MD 20849-1931, USA. DOWNLOADED FROM HTTP://TOS.ORG/OCEANOGRAPHY REGULAR ISSUE FEATURE EXPLORING THE “SHARKCANO” Biogeochemical Observations of the Kavachi Submarine Volcano (Solomon Islands) By Brennan T. Phillips, Matthew Dunbabin, Brad Henning, Corey Howell, Alex DeCiccio, Ashton Flinders, Katherine A. Kelley, Jarrod J. Scott, Simon Albert, Steven Carey, Rami Tsadok, and Alistair Grinham 160 Oceanography | Vol.29, No.4 ABSTRACT. An expedition to the Kavachi submarine volcano (Solomon Islands) Tuni, 1987). The most detailed investiga- in January 2015 was serendipitously timed with a rare lull in volcanic activity that tion prior to this study, which took place EXPLORING THE “SHARKCANO” permitted access to the inside of Kavachi’s active crater and its flanks. The isolated during a single day in May 2000, was con- Biogeochemical Observations of the Kavachi Submarine Volcano (Solomon Islands) location of Kavachi and its explosive behavior normally restrict scientific access to ducted from an approximate 1 km perim- the volcano’s summit, limiting previous observational efforts to surface imagery and eter surrounding the actively erupting peripheral water-column data. This article presents medium-resolution bathymetry of main peak. That study provided insights the main peak along with benthic imagery, biological observations of multiple trophic into the eruptive processes of Kavachi levels living inside the active crater, petrological and geochemical analysis of samples based on conductivity- temperature- from the crater rim, measurements of water temperature and gas flux over the summit, depth (CTD) casts and surface imagery and descriptions of the hydrothermal plume structure. A second peak was identified (see Baker et al., 2002). A magnitude 8.1 to the southwest of the main summit and displayed evidence of diffuse-flow venting. earthquake that shook the entire region Microbial samples collected from the summit indicate chemosynthetic populations in April 2007 prompted the reconnais- dominated by sulfur-reducing ε-proteobacteria. Populations of gelatinous animals, sance of a conspicuous surface plume fol- small fish, and sharks were observed inside the active crater, raising new questions lowing a subaerial eruption visible from about the ecology of active submarine volcanoes and the extreme environments in a nearby island (Wunderman, 2007). which large marine animals can exist. The latest published evidence of activ- ity was obtained by NASA’s EO-1 sat- INTRODUCTION eruptions has prevented scientists from ellite on January 29, 2014 (NASA Earth The New Georgia Island Group is the observing the proximal area of Kavachi’s Observatory, 2014), and it appears simi- result of a complex tectonic configu- summit crater. lar in behavior to the 2007 eruption. ration, characterized by subduction of Of the roughly 30 active submarine vol- This study was conducted during a the active Woodlark Spreading Center canoes known worldwide, only a few have quiescent phase, which allowed for the (WSC) beneath the Solomon Islands been observed during or closely following first closeup look inside and around the intra-oceanic arc. This triple junction is an active eruption, for example, Northwest shallow summit of Kavachi. Our research the site of active volcanism, crustal uplift Rota-1 (W.W. Chadwick et al., 2010), team took advantage of this rare lull in that closely matches subducted bathy- West Mata (Resing et al., 2011), El Hierro volcanic activity to gather geological, metric features from the WSC, and a pro- (Santana-Casiano et al., 2013), Kick’em biological, and oceanographic observa- posed “slab window” that leaves astheno- Jenny (Devine and Sigurdssson, 1995), tions using relatively simple equipment spheric mantle in direct contact with a and Axial Seamount (W.W. Chadwick and methodologies. We report here on thin overlying crust (Mann et al., 1998; et al., 2012, and references therein). our initial results, which include evi- J. Chadwick et al., 2009). The Kavachi Despite these limited studies, active sub- dence of diffuse-flow venting on a con- submarine volcano (8°59'S, 157°58'E) is marine volcanoes are considered import- firmed second peak, a megafaunal com- situated ~30 km northeast of the sub- ant natural laboratories for observing the munity living inside the active crater, duction zone and rises abruptly to the effects of ocean acidification on marine and insights into the eruptive processes surface from more than 1,000 m water animals (e.g., Hall-Spencer et al., 2008), and magma source characteristics of depth (Figure 1). By far the most active with Kavachi being an extreme example Kavachi’s active volcanism. volcano in the region, Kavachi is known of such an environment. for frequent phreatomagmatic (denoting Kavachi erupts nearly continuously. METHODS explosive water-magma interaction) and Reports of airborne steam and ash visible This work was conducted in January 2015 subaerial eruptions leading to occasional from shore are common, and the forma- with operations based out of Gatokae ephemeral island emergence (Johnson tion and erosion of multiple islands over Island, Western Province, Solomon and Tuni, 1987). The remote geographic the past century indicate the summit is Islands. Approaches to the summit crater location and inherent danger of frequent in a constant state of flux (Johnson and were made after several days of observing inactivity from a safe perimeter—normal eruptive activity for Kavachi is audible FACING PAGE. Article co-authors Alistair Grinham and Matthew Dunbabin prepare an autonomous on the surface, and no such sounds were surface drifter for deployment over Kavachi’s summit crater. Photo is taken looking north toward Vangunu Island, with the volcano’s surface plume visible in the middleground where the water heard during the course of this expedi- changes color from dark blue to light blue-green.” tion. All equipment used was lightweight, Oceanography | December 2016 161 relatively low cost, and deployed using transmission, and atmospheric pCO2 general trend depicting the volcano, sim- small boats. Down-looking images of the were deployed as described by Dunbabin ilar to swath editing in multibeam sonar seafloor paired with water-column mea- (2016). Total CO2 flux was calculated processing. This “cleaned” point-cloud surements were made using a GoPro using the drifter’s measurements of flux (~85,000 soundings; see online supple- camera in a deep-rated housing, battery- per unit area, which was extrapolated mental Figure S1) was then used to create powered lights, and a National Oceanic to represent the total size of the bubble three individual continuous curvature and Atmospheric Administration/Pacific zone. A downward-looking camera was spline surfaces, each with unique spatial Marine Environmental Laboratory mounted on the drifter, which logged its extent and resolution. This multisurface (NOAA/PMEL) Miniature Autonomous position, and after multiple runs through approach was necessary in order to accu- Plume Recorder (Walker et al., 2007) the bubble zone it was possible to esti- rately represent varying degrees of data mounted on an instrument frame that mate the total surface area by noting the density over the study area, with the most was raised and lowered with an electric appearance and disappearance of bubbles soundings concentrated at the summit fishing reel. Baited drop-camera record- on camera footage. caldera, and the least at the foot of the vol- ings were achieved using an autonomous We measured bathymetry with cano (Flinders et al., 2014). The three sur- National Geographic Remote Imaging a Lowrance HDS-5 echosounder faces (100 m study-wide, 35 m volcano- DropCam following methods described (50/200 kHz). IVS Fledermaus software focused, and 7 m summit-focused) were by Friedlander et al. (2014). Surface drift- was used to manually remove sound- then blended to create a single individual ers measuring water temperature, light ings that qualitatively deviated from a surface for visualization. Blending con- straints ensured that within each specific area, only the highest resolution surface 157°E 158°E 159°E 160°E would be used. Santa Scuba divers collected rock and bac- Isabel Vangunu terial samples by hand. Major and trace 8°S New element analyses were conducted using Georgia a Perkin Elmer Optima 3100 XL induc- 8.98°S Kavachi 9°S tively coupled plasma atomic emission spectrometer (ICP-AES) and a Thermo X-Series 2 quadrapole inductively cou- pled plasma mass spectrometer (ICP-MS; Kelley et al., 2003). The Marine Geological Sample Laboratory at the University of Rhode Island prepared the sample slides. Bacterial DNA was extracted using PowerSoil® DNA Isolation Kit (MO BIO Laboratories, Carlsbad, California), poly- 9.00°S merase chain reaction (PCR)-amplified using universal 16S rRNA gene primers (27F: AGR GTT YGA TYM TGG CTC AG, 1100R: GGG TTN CGN TCG TTG) and cloned with pGEM-T Easy (Promega, Madison, Wisconsin). After removal of 157.96°E 157.98°E vector and primer sequences, all clones 1 km were imported into the software pack- 0.1 km age mothur (http://www.mothur.org) to –1,000 –800 –600 –400 –200 Depth (m) –60 –45 –30 screen for putative chimeras and generate FIGURE 1.
Recommended publications
  • Supplementary Material
    Supplementary material S1 Eruptions considered Askja 1875 Askja, within Iceland’s Northern Volcanic Zone (NVZ), erupted in six phases of varying intensity, lasting 17 hours on 28–29 March 1875. The main eruption included a Subplinian phase (Unit B) followed by hydromagmatic fall and with some proximal pyroclastic flow (Unit C) and a magmatic Plinian phase (Unit D). Units C and D consisted of 4.5 x 108 m3 and 1.37 x 109 m3 of rhyolitic tephra, respectively [1–3]. Eyjafjallajökull 2010 Eyjafjallajökull is situated in the Eastern Volcanic Zone (EVZ) in southern Iceland. The Subplinian 2010 eruption lasted from 14 April to 21 May, resulting in significant disruption to European airspace. Plume heights ranged from 3 to 10 km and dispersing 2.7 x 105 m3 of trachytic tephra [4]. Hverfjall 2000 BP Hverfjall Fires occurred from a 50 km long fissure in the Krafla Volcanic System in Iceland’s NVZ. Magma interaction with an aquifer resulted in an initial basaltic hydromagmatic fall deposit from the Hverfjall vent with a total volume of 8 x 107 m3 [5]. Eldgja 10th century The flood lava eruption in the first half of the 10th century occurred from the Eldgja fissure within the Katla Volcanic System in Iceland’s EVZ. The mainly effusive basaltic eruption is estimated to have lasted between 6 months and 6 years, and included approximately 16 explosive episodes, both magmatic and hydromagmatic. A subaerial eruption produced magmatic Unit 7 (2.4 x 107 m3 of tephra) and a subglacial eruption produced hydromagmatic Unit 8 (2.8 x 107 m3 of tephra).
    [Show full text]
  • Land and Maritime Connectivity Project: Road Component Initial
    Land and Maritime Connectivity Project (RRP SOL 53421-001) Initial Environmental Examination Project No. 53421-001 Status: Draft Date: August 2020 Solomon Islands: Land and Maritime Connectivity Project – Multitranche Financing Facility Road Component Prepared by Ministry of Infrastructure Development This initial environmental examination is a document of the borrower. The views expressed herein do not necessarily represent those of the ADB’s Board of Directors, Management, or staff, and may be preliminary in nature. In preparing any country program or strategy, financing any project, or by making any designation of or reference to any particular territory or geographic area in this document, the Asian Development Bank does not intend to make any judgments as to the legal or other status of any territory or area. Solomon Islands: Land and Maritime Connectivity Project Road Component – Initial Environmental Examination Table of Contents Abbreviations iv Executive Summary v 1 Introduction 1 1.1 Background to the Project 1 1.2 Scope of the Environmental Assessment 5 2 Legal and Institutional Framework 6 2.1 Legal and Planning Framework 6 2.1.1 Country safeguard system 6 2.1.2 Other legislation supporting the CSS 7 2.1.3 Procedures for implementing the CSS 9 2.2 National Strategy and Plans 10 2.3 Safeguard Policy Statement 11 3 Description of the Subprojects 12 3.1 Location and Existing Conditions – SP-R1 12 3.1.1 Existing alignment 12 3.1.2 Identified issues and constraints 14 3.2 Location and Existing Conditions – SP-R5 15 3.2.1 Location
    [Show full text]
  • Plumbing System Dynamics at Kolumbo Submarine Volcano, Greece, Prior to the 1650 CE Explosive Eruption
    Goldschmidt2019 Abstract Plumbing system dynamics at Kolumbo submarine volcano, Greece, prior to the 1650 CE explosive eruption F. MASTROIANNI1,2,*, I. FANTOZZI2, C.M. PETRONE3, G.E. VOUGIOUKALAKIS4, E. BRASCHI5, L. FRANCALANCI2 1DST, University of Pisa, Via S. Maria 53, Pisa, IT (*correspondence: [email protected]) 2DST, University of Florence, Via G. LaPira, 4, Florence, IT 3The Natural History Museum, CromWell Road, London, UK 4HSGME, S. Lui 1, Olympic Village, Athens, GR 5CNR-IGG, Via G. LaPira, 4, Florence, IT Kolumbo is the largest of tWenty submarine volcanic cones tectonically aligned in the transtentional Anydros basin, NE of Santorini, representing one of the most seismically active Zones in the South Aegean Volcanic Arc. Kolumbo explosively erupted in 1650 CE, causing the death of 70 people on Santorini. Explorative cruises employing ROVs shoWed the presence of a high temperature (220°C) hydrothermal field With CO2-rich discharges and accumulation of acidic Water at the bottom of the crater (505m bsl) [1], increasing the haZard of this active system. A possible magma chamber Was recognized beloW the crater at depth 9-6 km by seismic data [2], Which is separated from the storage system of Santorini, as suggested also for the mantle source by geochemical data [3]. We present neW petrographic, geochemical and isotopic data (on Whole-rock, minerals and glasses) of samples collected during the cruises. Most samples represent the juvenile products of the 1650 CE activity, characterizing the different magmas interacting before the eruption. They consist of White rhyolitic pumices With grey and black bands, also including centimetric to millimetric, basaltic-andesitic enclaves.
    [Show full text]
  • Explosive Subaqueous Eruptions: the Influence of Volcanic Jets on Eruption Dynamics and Tephra Dispersal in Underwater Eruptions
    EXPLOSIVE SUBAQUEOUS ERUPTIONS: THE INFLUENCE OF VOLCANIC JETS ON ERUPTION DYNAMICS AND TEPHRA DISPERSAL IN UNDERWATER ERUPTIONS by RYAN CAIN CAHALAN A DISSERTATION Presented to the Department of Earth ScIences and the Graduate School of the UniversIty of Oregon In partIaL fulfiLLment of the requirements for the degree of Doctor of PhiLosophy December 2020 DISSERTATION APPROVAL PAGE Student: Ryan CaIn CahaLan Title: ExplosIve Subaqueous EruptIons: The Influence of Volcanic Jets on EruptIon DynamIcs and Tephra DIspersaL In Underwater EruptIons This dissertatIon has been accepted and approved in partIaL fulfiLLment of the requirements for the Doctor of PhiLosophy degree in the Department of Earth ScIences by: Dr. Josef Dufek ChaIrperson Dr. Thomas GIachettI Core Member Dr. Paul WaLLace Core Member Dr. KeLLy Sutherland InstItutIonaL RepresentatIve and Kate Mondloch Interim VIce Provost and Dean of the Graduate School OriginaL approvaL sIgnatures are on fiLe wIth the UniversIty of Oregon Graduate School. Degree awarded December 2020 II © 2020 Ryan Cain Cahalan III DISSERTATION ABSTRACT Ryan CaIn CahaLan Doctor of PhiLosophy Department of Earth ScIences December 2020 Title: ExplosIve Subaqueous EruptIons: The Influence of Volcanic Jets on EruptIon DynamIcs and Tephra DIspersaL In Underwater EruptIons Subaqueous eruptIons are often overlooked in hazard consIderatIons though they represent sIgnificant hazards to shipping, coastLInes, and in some cases, aIrcraft. In explosIve subaqueous eruptIons, volcanic jets transport fragmented tephra and exsolved gases from the conduit into the water column. Upon eruptIon the volcanic jet mIxes wIth seawater and rapidly cools. This mIxing and assocIated heat transfer ultImateLy determInes whether steam present in the jet wILL completeLy condense or rise to breach the sea surface and become a subaeriaL hazard.
    [Show full text]
  • A Different Ocean Acidification Hazard—The Kolumbo Submarine Volcano
    A different ocean acidifi cation hazard—The Kolumbo submarine volcano example Peter G. Brewer Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, California 95039, USA Detailed knowledge of the geochemistry of CO2, the signature mol- column with its large capacity for dissolution. If transport overcomes this ecule of the 21st century, is a modern day requirement for almost all geo- aqueous chemical sink—the bubble streams typically dissolve within ~10 chemists. Concerns over CO2 driven contemporary climate change, its m rise—the gas will be exposed to the atmosphere at the wind-swept open relationship to past climates in Earth history, skills required for geologic ocean surface. CO2 sequestration, and the rapid emergence of ocean acidifi cation as an There is also the matter of scale. The estimated 400 metric tons environmental threat are all prime subject matter for the literate geoscien- of dissolved CO2 in the Kolumbo crater is far less than the 100,000 – tist today. In this issue of Geology, Carey et al. (2013, p. 1035) describe 300,000 tons believed to have been released in the Lake Nyos event. Of a new, interesting, and quite powerful natural example of the intersection course, we could be at an early stage of the CO2 buildup, and over time, of these concerns in describing the build-up of a large body of acidic, far larger quantities could accumulate. Carey et al. show that the local dense CO2 rich sea water in the shallow crater of the Kolumbo volcano source is an extensive hydrothermal vent fi eld, releasing almost pure close to the Mediterranean island of Santorini.
    [Show full text]
  • “Poseidic” Explosive Eruptions at Loihi Seamount, Hawaii
    Downloaded from geology.gsapubs.org on October 5, 2010 “Poseidic” explosive eruptions at Loihi Seamount, Hawaii C. Ian Schipper*1, James D.L. White1, Bruce F. Houghton2, Nobumichi Shimizu3, and Robert B. Stewart4 1Geology Department, University of Otago, PO Box 56, Leith Street, Dunedin 9016, New Zealand 2School of Ocean and Earth Science and Technology (SOEST), University of Hawai’ i at Ma¯noa, 1680 East-West Road, Honolulu, Hawaii 98622, USA 3Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA 4Soil and Earth Sciences, Institute of Natural Resources (INR), Massey University, PB 11-222, Palmerston North 4474, New Zealand ABSTRACT (A.D. 1996) of Loihi’s ~400 ka history (Moore Much remains unknown about submarine explosive eruptions. Their deposits are found et al. 1982; Garcia et al. 2006). to great depths in all the world’s oceans, but eruptions are typically described by analogy Here we describe the southern cone on the to a subaerial nomenclature that ignores the substantial and inevitable infl uences of hydro- southeast summit plateau of Loihi (18°54′N, static pressure and magma-water interaction at submerged edifi ces. Here we explore mag- 155°15′W), examined in October 2006 with matic volatile exsolution and magma-water interaction for a pyroclastic cone-forming erup- the Hawaiian Undersea Research Laboratory’s tion at ~1 km depth on Loihi Seamount, Hawaii. We examine vesicle textures in lapilli—the Pisces IV submersible. The cone is ~60 m high, physical manifestation of degassing; dissolved volatiles in matrix glasses and olivine-hosted 4 × 106 m3 in volume, with a faintly discernable glass inclusions—the geochemical record of ascent and volatile exsolution; and fi ne ash summit rim we interpret as the edge of a partly morphology—the evidence for if and how external water assisted in fragmentation.
    [Show full text]
  • Exploring Submarine Arc Volcanoes Steven Carey University of Rhode Island, [email protected]
    University of Rhode Island DigitalCommons@URI Graduate School of Oceanography Faculty Graduate School of Oceanography Publications 2007 Exploring Submarine Arc Volcanoes Steven Carey University of Rhode Island, [email protected] Haraldur Sigurdsson University of Rhode Island Follow this and additional works at: https://digitalcommons.uri.edu/gsofacpubs Terms of Use All rights reserved under copyright. Citation/Publisher Attribution Carey, S., and H. Sigurdsson. 2007. Exploring submarine arc volcanoes. Oceanography 20(4):80–89, https://doi.org/10.5670/ oceanog.2007.08. Available at: https://doi.org/10.5670/oceanog.2007.08 This Article is brought to you for free and open access by the Graduate School of Oceanography at DigitalCommons@URI. It has been accepted for inclusion in Graduate School of Oceanography Faculty Publications by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. This article has This been published in or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval portionthe ofwith any permitted articleonly photocopy by is of machine, reposting, this means or collective or other redistirbution SP ec I A L Iss U E On Ocean E X P L O R ATIO N Oceanography , Volume 20, Number 4, a quarterly journal of The 20, Number 4, a quarterly , Volume O ceanography Society. Copyright 2007 by The 2007 by Copyright Society. ceanography Exploring O ceanography Society. All rights All reserved. Society. ceanography O Submarine Arc Volcanoes or Th e [email protected] Send Society. ceanography to: correspondence all B Y S T even C A R E Y an D H A R A LDUR SIGURD ss O N Three quarters of Earth’s volcanic activ- although a significant part of arc volca- tion of tsunamis (Latter, 1981).
    [Show full text]
  • Geology, Geochemistry and Earthquake History of Lō`Ihi Seamount, Hawai`I
    INVITED REVIEW Geology, Geochemistry and Earthquake History of Lō`ihi Seamount, Hawai`i Michael O. Garcia1*, Jackie Caplan-Auerbach2, Eric H. De Carlo3, M.D. Kurz4 and N. Becker1 1Department of Geology and Geophysics, University of Hawai`i, Honolulu, HI, USA 2U.S.G.S., Alaska Volcano Observatory, Anchorage, AK, USA 3Department of Oceanography, University of Hawai`i, Honolulu, HI, USA 4Department of Chemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA *Corresponding author: Tel.: 001-808-956-6641, FAX: 001-808-956-5521; email: [email protected] Key words: Loihi, seamount, Hawaii, petrology, geochemistry, earthquakes Abstract A half century of investigations are summarized here on the youngest Hawaiian volcano, Lō`ihi Seamount. It was discovered in 1952 following an earthquake swarm. Surveying in 1954 determined it has an elongate shape, which is the meaning of its Hawaiian name. Lō`ihi was mostly forgotten until two earthquake swarms in the 1970’s led to a dredging expedition in 1978, which recovered young lavas. This led to numerous expeditions to investigate the geology, geophysics, and geochemistry of this active volcano. Geophysical monitoring, including a real- time submarine observatory that continuously monitored Lō`ihi’s seismic activity for three months, captured some of the volcano’s earthquake swarms. The 1996 swarm, the largest recorded in Hawai`i, was preceded by at least one eruption and accompanied by the formation of a ~300-m deep pit crater, renewing interest in this submarine volcano. Seismic and petrologic data indicate that magma was stored in a ~8-9 km deep reservoir prior to the 1996 eruption.
    [Show full text]
  • Recent Eruptions Between 2012 and 2018 Discovered at West Mata Submarine Volcano (NE Lau Basin, SW Pacific) and Characterized by New Ship, AUV, and ROV Data
    fmars-06-00495 August 16, 2019 Time: 18:14 # 1 ORIGINAL RESEARCH published: 20 August 2019 doi: 10.3389/fmars.2019.00495 Recent Eruptions Between 2012 and 2018 Discovered at West Mata Submarine Volcano (NE Lau Basin, SW Pacific) and Characterized by New Ship, AUV, and ROV Data William W. Chadwick Jr.1*, Kenneth H. Rubin2, Susan G. Merle3, Andra M. Bobbitt3, Tom Kwasnitschka4 and Robert W. Embley3 1 NOAA Pacific Marine Environmental Laboratory, Newport, OR, United States, 2 Department of Earth Sciences, University of Hawai’i at Manoa,¯ Honolulu, HI, United States, 3 CIMRS, Oregon State University, Newport, OR, United States, 4 GEOMAR, Helmholtz Centre for Ocean Research, Kiel, Germany West Mata is a submarine volcano located in the SW Pacific Ocean between Fiji and Samoa in the NE Lau Basin. West Mata was discovered to be actively erupting at its summit in September 2008 and May 2009. Water-column chemistry and hydrophone Edited by: data suggest it was probably continuously active until early 2011. Subsequent repeated Cristina Gambi, Marche Polytechnic University, Italy bathymetric surveys of West Mata have shown that it changed to a style of frequent Reviewed by: but intermittent eruptions away from the summit since then. We present new data Paraskevi Nomikou, from ship-based bathymetric surveys, high-resolution bathymetry from an autonomous National and Kapodistrian University underwater vehicle, and observations from remotely operated vehicle dives that of Athens, Greece Simon James Barker, document four additional eruptions between 2012 and 2018. Three of those eruptions Victoria University of Wellington, occurred between September 2012 and March 2016; one near the summit on the upper New Zealand ENE rift, a second on the NE flank away from any rift zone, and a third at the NE base *Correspondence: William W.
    [Show full text]
  • Microbiology of Seamounts Is Still in Its Infancy
    or collective redistirbution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The approval portionthe ofwith any articlepermitted only photocopy by is of machine, reposting, this means or collective or other redistirbution This article has This been published in MOUNTAINS IN THE SEA Oceanography MICROBIOLOGY journal of The 23, Number 1, a quarterly , Volume OF SEAMOUNTS Common Patterns Observed in Community Structure O ceanography ceanography S BY DAVID EmERSON AND CRAIG L. MOYER ociety. © 2010 by The 2010 by O ceanography ceanography O ceanography ceanography ABSTRACT. Much interest has been generated by the discoveries of biodiversity InTRODUCTION S ociety. ociety. associated with seamounts. The volcanically active portion of these undersea Microbial life is remarkable for its resil- A mountains hosts a remarkably diverse range of unusual microbial habitats, from ience to extremes of temperature, pH, article for use and research. this copy in teaching to granted ll rights reserved. is Permission S ociety. ociety. black smokers rich in sulfur to cooler, diffuse, iron-rich hydrothermal vents. As and pressure, as well its ability to persist S such, seamounts potentially represent hotspots of microbial diversity, yet our and thrive using an amazing number or Th e [email protected] to: correspondence all end understanding of the microbiology of seamounts is still in its infancy. Here, we of organic or inorganic food sources. discuss recent work on the detection of seamount microbial communities and the Nowhere are these traits more evident observation that specific community groups may be indicative of specific geochemical than in the deep ocean.
    [Show full text]
  • Anatomy of an Active Submarine Volcano
    Downloaded from geology.gsapubs.org on July 28, 2014 Anatomy of an active submarine volcano A.F. Arnulf1, A.J. Harding1, G.M. Kent2, S.M. Carbotte3, J.P. Canales4, and M.R. Nedimović3,5 1Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California–San Diego, La Jolla, California 92093, USA 2Nevada Seismological Laboratory, 0174, University of Nevada–Reno, Reno, Nevada 89557, USA 3Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA 4Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02540, USA 5Department of Earth Sciences, Dalhousie University, Halifax, Nova Scotia B3H4J1, Canada ABSTRACT To date, seismic experiments have been one Most of the magma erupted at mid-ocean ridges is stored in a mid-crustal melt lens that lies of the keys in our understanding of the inter- at the boundary between sheeted dikes and gabbros. Nevertheless, images of the magma path- nal structure of volcanic systems (Okubo et al., ways linking this melt lens to the overlying eruption site have remained elusive. Here, we have 1997; Kent et al., 2000; Zandomeneghi et al., used seismic methods to image the thickest magma reservoir observed beneath any spreading 2009; Paulatto et al., 2012). However, most ex- center to date, which is principally attributed to the juxtaposition of the Juan de Fuca Ridge periments, especially subaerial-based ones, are with the Cobb hotspot (northwestern USA). Our results reveal a complex melt body, which restricted to refraction geometries with limited is ~14 km long, 3 km wide, and up to 1 km thick, beneath the summit caldera.
    [Show full text]
  • Sharon R. Allen Is a Physical Volcanologist Who Has Worked On
    Sharon R. Allen is a physical volcanologist who Timothy H. Druitt is a volcanologist who works has worked on the processes and products of felsic on the processes and products of explosive volca­ effusive and explosive volcanism in both subaerial nism. His approaches include the field study of and submarine environments from a range of tec­ volcanic products, laboratory analogue experi­ tonic settings. She has been researching the South ments, and the petrology and chemistry of magmas. Aegean volcanic arc since 1993, first as a PhD He has used Santorini Volcano (Greece) as a natural student at Monash University (Australia), later as a laboratory for identifying fundamental questions post­doc at the University of Tasmania (UTAS) (Australia), and currently related to volcanism and for testing hypotheses. He obtained his PhD as a university associate at UTAS. Her scientific interests include subae­ at the University of Cambridge (UK) and is currently Professor of rial caldera forming eruptions, the dynamics of pyroclastic currents Volcanology at Clermont­Auvergne University (France). He was Editor­ on land and when interacting with water, submarine pyroclastic erup­ in­Chief of the Bulletin of Volcanology for four years and received the tions and mechanisms for the formation of pumice in submarine set­ 2018 Norman L. Bowen Award of the American Geophysical Union. tings. Her approach includes field studies of volcanic products and laboratory analogue experimentation. Lorella Francalanci is a geochemist and volcano­ logist who investigates active volcanoes to reveal Olivier Bachmann is a professor of volcanology the pre­eruptive processes that are relevant to the and magmatic petrology at the Eidgenössische dynamics of volcanic eruptions.
    [Show full text]