DOCSLIB.ORG

On the Formation of Hydrothermal Vents and Cold Seeps in the Guaymas Basin, Gulf of California

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
On the Formation of Hydrothermal Vents and Cold Seeps in the Guaymas Basin, Gulf of California Biogeosciences, 15, 5715–5731, 2018 https://doi.org/10.5194/bg-15-5715-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. On the formation of hydrothermal vents and cold seeps in the Guaymas Basin, Gulf of California Sonja Geilert1, Christian Hensen1, Mark Schmidt1, Volker Liebetrau1, Florian Scholz1, Mechthild Doll2, Longhui Deng3, Annika Fiskal3, Mark A. Lever3, Chih-Chieh Su4, Stefan Schloemer5, Sudipta Sarkar6, Volker Thiel7, and Christian Berndt1 1GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1–3, 24148 Kiel, Germany 2Faculty of Geosciences, University of Bremen, Klagenfurter-Straße 4, 28359 Bremen, Germany 3Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, 8092 Zurich, Switzerland 4Institute of Oceanography, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan 5Federal Institute for Geosciences and Natural Resources, Stilleweg 2, 30655 Hannover, Germany 6Department of Earth and Climate Science, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Maharashtra-411008, India 7Geobiology, Geoscience Centre, University of Göttingen, Goldschmidtstr. 3, 37077 Göttingen, Germany Correspondence: Sonja Geilert ([email protected]) Received: 8 January 2018 – Discussion started: 6 February 2018 Revised: 4 September 2018 – Accepted: 5 September 2018 – Published: 27 September 2018 Abstract. Magmatic sill intrusions into organic-rich sedi- lated that deep fluid and thermogenic gas flow ceased 28 to ments cause the release of thermogenic CH4 and CO2. Pore 7 kyr ago. These findings imply a short lifetime of hydrother- fluids from the Guaymas Basin (Gulf of California), a sed- mal systems, limiting the time of unhindered carbon release imentary basin with recent magmatic activity, were investi- as suggested in previous modeling studies. Consequently, ac- gated to constrain the link between sill intrusions and fluid tivation and deactivation mechanisms of these systems need seepage as well as the timing of sill-induced hydrothermal to be better constrained for the use in climate modeling ap- activity. Sampling sites were close to a hydrothermal vent proaches. field at the northern rift axis and at cold seeps located up to 30 km away from the rift. Pore fluids close to the active hy- drothermal vent field showed a slight imprint by hydrother- mal fluids and indicated a shallow circulation system trans- 1 Introduction porting seawater to the hydrothermal catchment area. Geo- chemical data of pore fluids at cold seeps showed a mainly Abrupt climate change events in Earth’s history have been ambient diagenetic fluid composition without any imprint re- partly related to the injection of large amounts of greenhouse lated to high temperature processes at greater depth. Seep gases into the atmosphere (e.g., Svensen et al., 2004; Gut- communities at the seafloor were mainly sustained by mi- jahr et al., 2017). Among the most prominent of these events crobial methane, which rose along pathways formed earlier was the Paleocene–Eocene Thermal Maximum (PETM) dur- ◦ by hydrothermal activity, driving the anaerobic oxidation of ing which the Earth’s atmosphere warmed by about 8 C in methane (AOM) and the formation of authigenic carbonates. less than 10 000 years (Zachos et al., 2003). The PETM was Overall, our data from the cold seep sites suggest that possibly triggered by the emission of about 2000 Gt of car- at present, sill-induced hydrothermalism is not active away bon (Dickens, 2003; Zachos et al., 2003). The processes dis- from the ridge axis, and the vigorous venting of hydrothermal cussed regarding the release of these large amounts of car- fluids is restricted to the ridge axis. Using the sediment thick- bon in a relatively short time are gas hydrate dissociation, ness above extinct conduits and carbonate dating, we calcu- volcanic eruptions as well as igneous intrusions into organic- rich sediments, triggering the release of carbon during con- Published by Copernicus Publications on behalf of the European Geosciences Union. 5716 S. Geilert et al.: On the formation of hydrothermal vents and cold seeps tact metamorphism (Svensen et al., 2004; Aarnes et al., 2010; cline just as quickly (< 10 kyr) (Bani-Hassan, 2012; Iyer et Gutjahr et al., 2017). al., 2017). The Guaymas Basin in the Gulf of California is consid- During the expedition SO241 by RV SONNE in June/ July ered one of the few key sites to study carbon release in a rift 2015 a new hydrothermal vent field was discovered at the basin exposed to high sedimentation rates. A newly discov- flank of the northern trough (Fig. 1; Berndt et al., 2016). The ered vent field in the Guaymas Basin, which releases large discovered mound rises up to 100 m above the seafloor and amounts of CH4 and CO2 up to several hundreds of meters predominant black-smoker-type vents suggest similar end- into the water column (Berndt et al., 2016), stimulated the member temperatures and geochemical composition found discussion on the climate potential of magmatic intrusions at the southern trough (Von Damm et al., 1985; Von Damm, into organic-rich sediments (e.g., Svensen et al., 2004). 1990; Berndt et al., 2016). The hydrothermal vent system The Gulf of California is located between the Mexican emits methane-rich fluids with a helium isotope signature mainland and the Baja California peninsula, north of the East indicative of fluids in contact with mid-ocean ridge basalt Pacific Rise (EPR; Fig. 1). The spreading regime at EPR con- (Berndt et al., 2016). On this cruise, we sampled this re- tinues into the Gulf of California and changes from a ma- cently discovered hydrothermal vent field and some of the ture, open-ocean type to an early opening continental rifting off-axis seeps above sill intrusions described by Lizarralde et environment with spreading rates of about 6 cm yr−1 (Cur- al. (2010). The aim of this study was to investigate the fluid ray and Moore, 1982). Its spreading axis consists of two and gas compositions of the off-axis seeps in order to identify graben systems (northern and southern troughs) offset by a the influence of sill intrusions on fluid circulation, gas com- transform fault (Fig. 1). The Guaymas Basin, which is about position, and the timing of hydrothermal activity. The overall 240 km long, is around 60 km wide, reaches water depths motivation was thus to explore the regional and temporal ex- of up to 2000 m, and is known as a region of vigorous hy- tent of hydrothermal activity in the area and to provide better drothermal activity (e.g., Curray and Moore, 1982; Gieskes constraints on carbon release from sedimented ridge systems. et al., 1982; Von Damm et al., 1985). Hydrothermal activ- ity in the Guaymas Basin was first reported in the southern trough (e.g., Lupton, 1979; Gieskes et al., 1982; Campbell 2 Materials and methods and Gieskes, 1984; Von Damm et al., 1985). Here, fluids em- anate partly from black-smoker-type vents at temperatures 2.1 Sampling devices and strategy of up to 315 ◦C (Von Damm et al., 1985). The rifting envi- During the RV SONNE expedition SO241, seven sites across ronment in the Guaymas Basin shows a high sediment accu- the central graben of the Guaymas basin were investigated mulation rate of up to 0.8–2.5 m kyr−1, resulting in organic- (Fig. 1). Site-specific sampling and data recording were per- rich sedimentary deposits of several hundreds of meters in formed using (1) a video-guided multi-corer (MUC), (2) a thickness (e.g., Calvert, 1966; DeMaster, 1981; Berndt et al., gravity corer (GC), (3) temperature loggers attached to a GC 2016). The high sedimentation rate is caused by high biolog- or sediment probe, (4) a video-guided VCTD/Rosette wa- ical productivity in the water column and an influx of ter- ter sampler, and (5) a video-guided hydraulic grab (VgHG). rigenous matter from the Mexican mainland (Calvert, 1966). Sites were selected according to published data on the lo- Sills and dikes intruding into the sediment cover have a sub- cations of seeps (Lizarralde et al., 2010) and seismic data stantial impact on the distribution of heat flow, other environ- acquired during the cruise (see below). mental conditions, and thus early diagenetic processes within the basin (Biddle et al., 2012; Einsele et al., 1980; Kast- 2.1.1 Seismic data recording ner, 1982; Kastner and Siever, 1983; Simoneit et al., 1992; Lizarralde et al., 2010; Teske et al., 2014). Seismic data were collected using a Geometrics GeoEel Magmatic intrusions and cold seeps at the seafloor were Streamer of 150 and 183.5 m length and 96 and 112 channels, observed up to 50 km away from the rift axis, and a re- respectively. Two generator-injector guns in harmonic mode cently active magmatic process triggering the alteration of (105/105 cubic inch) served as the seismic source. Process- organic-rich sediments and releasing thermogenic CH4 and ing included navigation processing (1.5625 m crooked line CO2 was proposed by Lizarralde et al. (2010). These au- binning), 20, 45, 250, and 400 Hz frequency filtering, and thors attributed elevated CH4 concentrations and tempera- post-stack Stolt migration with water velocity yielding an ap- ture anomalies in the water column to active thermogenic proximately 2 m horizontal and 5 m vertical resolution close CH4 production driven by contact metamorphism. Accord- to the seafloor. ing to Lizarralde et al. (2010) ongoing off-axis hydrothermal − activity may cause a maximum carbon flux of 240 kt C yr 1 2.1.2 Sediment and pore fluid sampling through the seafloor into the ocean and potentially into the at- mosphere. However, modeling studies investigating the life- At seepage and vent sites, the video-guided MUC was used time of such sill-induced hydrothermalism show that initial to discover recent fluid release, which was indicated by typ- CH4 and CO2 release is intense and vigorous but can de- ical chemosynthetic biological communities at the seafloor Biogeosciences, 15, 5715–5731, 2018 www.biogeosciences.net/15/5715/2018/ S.
Load more

Recommended publications
  • Hydrothermal Vents. Teacher's Notes
    Hydrothermal Vents Hydrothermal Vents. Teacher’s notes. A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. They are usually volcanically active. Seawater penetrates into fissures of the volcanic bed and interacts with the hot, newly formed rock in the volcanic crust. This heated seawater (350-450°) dissolves large amounts of minerals. The resulting acidic solution, containing metals (Fe, Mn, Zn, Cu) and large amounts of reduced sulfur and compounds such as sulfides and H2S, percolates up through the sea floor where it mixes with the cold surrounding ocean water (2-4°) forming mineral deposits and different types of vents. In the resulting temperature gradient, these minerals provide a source of energy and nutrients to chemoautotrophic organisms that are, thus, able to live in these extreme conditions. This is an extreme environment with high pressure, steep temperature gradients, and high concentrations of toxic elements such as sulfides and heavy metals. Black and white smokers Some hydrothermal vents form a chimney like structure that can be as 60m tall. They are formed when the minerals that are dissolved in the fluid precipitates out when the super-heated water comes into contact with the freezing seawater. The minerals become particles with high sulphur content that form the stack. Black smokers are very acidic typically with a ph. of 2 (around that of vinegar). A black smoker is a type of vent found at depths typically below 3000m that emit a cloud or black material high in sulphates. White smokers are formed in a similar way but they emit lighter-hued minerals, for example barium, calcium and silicon.
    [Show full text]
  • Cold Seep Benthic Communities in Japan Subduction Zones: Spatial Organization, Trophic Strategies and Evidence for Temporal Evolution*
    MARINE ECOLOGY - PROGRESS SERIES Vol. 40: 115-126. 1987 Published October 7 Mar. Ecol. Prog. Ser. Cold seep benthic communities in Japan subduction zones: spatial organization, trophic strategies and evidence for temporal evolution* S. Kim Juniper", Myriam Sibuet IFREMER, Centre de Brest. BP 337. F-29273 Brest Cedex. France ABSTRACT: Submersible exploration of the Japan subduction zones has revealed benthic communities dominated by clams (Calyptogena spp.) around sed~mentporewater seeps at depths from 3850 to 6000 m. Photographic and video records were used to produce microcartographlc reconstructions of 3 contrasting cold seep sites. Spatial and abundance relations of megafauna lead us to propose several hypotheses regard~ngthe ecological functioning of these cold seep communities. We dlst~nguish between the likely direct use of reducing substances in venting fluids by Calyptogena-bacteria symbioses and indirect usage by accompanying abyssal species not known to harbour symbionts. Microdistribution and known or presumed feedmg modes of the accompanying species indicate 2 different sources of organic matter enrichment within cold seep sites: organic debris originating from bivalve colonies, and enrichment of extensive areas of surrounding surface sediments where weaker, more hffuse porewater seepage may support chemosynthetic production by free-living bacteria. The occurrence of colony-like groupings of empty Calyptogena valves indicates that cold seeps are ephemeral, with groups of living clams, mixed living and dead clams, and empty dissolving shells marlung the course of a cycle of porewater venting and offering clues to the recent history of cold seep activity. INTRODUCTION al. 1985). One of the bivalve species from this area has been shown to harbour symbiotic bacteria in its gill The discovery of deep-sea hydrothermal vents has tissue and to oxidise methane (Childress et al.
    [Show full text]
  • Chemotaxonomic Characterization of the Thaumarchaeal Lipidome
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Aberdeen University Research Archive Chemotaxonomic characterization of the thaumarchaeal lipidome Running title: Comparative analysis of the thaumarchaeal lipidome Felix J. Elling1+, Martin Könneke1,2#, Graeme W. Nicol3, Michaela Stieglmeier4, Barbara Bayer5, Eva Spieck6, José R. de la Torre7, Kevin W. Becker1†, Michael Thomm8, James I. Prosser9, Gerhard J. Herndl5,10, Christa Schleper4, Kai-Uwe Hinrichs1 1 Organic Geochemistry Group, MARUM - Center for Marine Environmental Sciences & Department of Geosciences, University of Bremen, 28359 Bremen, Germany. 2 Marine Archaea Group, MARUM Center for Marine Environmental Sciences & Department of Geosciences, University of Bremen, 28359 Bremen, Germany. 3 Environmental Microbial Genomics, Laboratoire Ampère, École Centrale de Lyon, Université de Lyon, 69134 Ecully, France 4 Department of Ecogenomics and Systems Biology, Center of Ecology, University of Vienna, 1090 Vienna, Austria. 5 Department of Limnology and BioOceanography, Center of Ecology, University of Vienna, 1090 Vienna, Austria. 6 Biocenter Klein Flottbek, Department of Microbiology and Biotechnology, University of Hamburg, 22609 Hamburg, Germany. 7 Department of Biology, San Francisco State University, San Francisco, CA, USA. 8 Lehrstuhl für Mikrobiologie und Archaeenzentrum, Universität Regensburg, 93053 Regensburg, Germany. 9 Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, Aberdeen, AB24 3UU, United Kingdom. 10 Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, Utrecht University, 1790 AB Den Burg, Texel, The Netherlands #Corresponding author. Tel.: + 49 421 218 65747. Fax: +49 421 218 65715. E-mail: [email protected] +present address: Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA.
    [Show full text]
  • Introduction to Co2 Chemistry in Sea Water
    INTRODUCTION TO CO2 CHEMISTRY IN SEA WATER Andrew G. Dickson Scripps Institution of Oceanography, UC San Diego Mauna Loa Observatory, Hawaii Monthly Average Carbon Dioxide Concentration Data from Scripps CO Program Last updated August 2016 2 ? 410 400 390 380 370 2008; ~385 ppm 360 350 Concentration (ppm) 2 340 CO 330 1974; ~330 ppm 320 310 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 Year EFFECT OF ADDING CO2 TO SEA WATER 2− − CO2 + CO3 +H2O ! 2HCO3 O C O CO2 1. Dissolves in the ocean increase in decreases increases dissolved CO2 carbonate bicarbonate − HCO3 H O O also hydrogen ion concentration increases C H H 2. Reacts with water O O + H2O to form bicarbonate ion i.e., pH = –lg [H ] decreases H+ and hydrogen ion − HCO3 and saturation state of calcium carbonate decreases H+ 2− O O CO + 2− 3 3. Nearly all of that hydrogen [Ca ][CO ] C C H saturation Ω = 3 O O ion reacts with carbonate O O state K ion to form more bicarbonate sp (a measure of how “easy” it is to form a shell) M u l t i p l e o b s e r v e d indicators of a changing global carbon cycle: (a) atmospheric concentrations of carbon dioxide (CO2) from Mauna Loa (19°32´N, 155°34´W – red) and South Pole (89°59´S, 24°48´W – black) since 1958; (b) partial pressure of dissolved CO2 at the ocean surface (blue curves) and in situ pH (green curves), a measure of the acidity of ocean water.
    [Show full text]
  • Phylogenetics of Archaeal Lipids Amy Kelly 9/27/2006 Outline
    Phylogenetics of Archaeal Lipids Amy Kelly 9/27/2006 Outline • Phlogenetics of Archaea • Phlogenetics of archaeal lipids • Papers Phyla • Two? main phyla – Euryarchaeota • Methanogens • Extreme halophiles • Extreme thermophiles • Sulfate-reducing – Crenarchaeota • Extreme thermophiles – Korarchaeota? • Hyperthermophiles • indicated only by environmental DNA sequences – Nanoarchaeum? • N. equitans a fast evolving euryarchaeal lineage, not novel, early diverging archaeal phylum – Ancient archael group? • In deepest brances of Crenarchaea? Euryarchaea? Archaeal Lipids • Methanogens – Di- and tetra-ethers of glycerol and isoprenoid alcohols – Core mostly archaeol or caldarchaeol – Core sometimes sn-2- or Images removed due to sn-3-hydroxyarchaeol or copyright considerations. macrocyclic archaeol –PMI • Halophiles – Similar to methanogens – Exclusively synthesize bacterioruberin • Marine Crenarchaea Depositional Archaeal Lipids Biological Origin Environment Crocetane methanotrophs? methane seeps? methanogens, PMI (2,6,10,15,19-pentamethylicosane) methanotrophs hypersaline, anoxic Squalane hypersaline? C31-C40 head-to-head isoprenoids Smit & Mushegian • “Lost” enzymes of MVA pathway must exist – Phosphomevalonate kinase (PMK) – Diphosphomevalonate decarboxylase – Isopentenyl diphosphate isomerase (IPPI) Kaneda et al. 2001 Rohdich et al. 2001 Boucher et al. • Isoprenoid biosynthesis of archaea evolved through a combination of processes – Co-option of ancestral enzymes – Modification of enzymatic specificity – Orthologous and non-orthologous gene
    [Show full text]
  • Miniaturized Biosignature Analysis Reveals Implications for the Formation of Cold Seep Carbonates at Hydrate Ridge (Off Oregon, USA) T
    Miniaturized biosignature analysis reveals implications for the formation of cold seep carbonates at Hydrate Ridge (off Oregon, USA) T. Leefmann, J. Bauermeister, A. Kronz, V. Liebetrau, J. Reitner, V. Thiel To cite this version: T. Leefmann, J. Bauermeister, A. Kronz, V. Liebetrau, J. Reitner, et al.. Miniaturized biosignature analysis reveals implications for the formation of cold seep carbonates at Hydrate Ridge (off Oregon, USA). Biogeosciences Discussions, European Geosciences Union, 2007, 4 (6), pp.4443-4458. hal- 00297947 HAL Id: hal-00297947 https://hal.archives-ouvertes.fr/hal-00297947 Submitted on 28 Nov 2007 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Biogeosciences Discuss., 4, 4443–4458, 2007 Biogeosciences www.biogeosciences-discuss.net/4/4443/2007/ Discussions BGD © Author(s) 2007. This work is licensed 4, 4443–4458, 2007 under a Creative Commons License. Biogeosciences Discussions is the access reviewed discussion forum of Biogeosciences Biosignature analysis of cold seep carbonates T. Leefmann et al. Miniaturized biosignature analysis reveals Title Page implications for the formation of cold Abstract Introduction seep carbonates at Hydrate Ridge Conclusions References (off Oregon, USA) Tables Figures T. Leefmann1, J. Bauermeister1, A. Kronz1, V.
    [Show full text]
  • Biodiversity and Trophic Ecology of Hydrothermal Vent Fauna Associated with Tubeworm Assemblages on the Juan De Fuca Ridge
    Biogeosciences, 15, 2629–2647, 2018 https://doi.org/10.5194/bg-15-2629-2018 © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. Biodiversity and trophic ecology of hydrothermal vent fauna associated with tubeworm assemblages on the Juan de Fuca Ridge Yann Lelièvre1,2, Jozée Sarrazin1, Julien Marticorena1, Gauthier Schaal3, Thomas Day1, Pierre Legendre2, Stéphane Hourdez4,5, and Marjolaine Matabos1 1Ifremer, Centre de Bretagne, REM/EEP, Laboratoire Environnement Profond, 29280 Plouzané, France 2Département de sciences biologiques, Université de Montréal, C.P. 6128, succursale Centre-ville, Montréal, Québec, H3C 3J7, Canada 3Laboratoire des Sciences de l’Environnement Marin (LEMAR), UMR 6539 9 CNRS/UBO/IRD/Ifremer, BP 70, 29280, Plouzané, France 4Sorbonne Université, UMR7144, Station Biologique de Roscoff, 29680 Roscoff, France 5CNRS, UMR7144, Station Biologique de Roscoff, 29680 Roscoff, France Correspondence: Yann Lelièvre ([email protected]) Received: 3 October 2017 – Discussion started: 12 October 2017 Revised: 29 March 2018 – Accepted: 7 April 2018 – Published: 4 May 2018 Abstract. Hydrothermal vent sites along the Juan de Fuca community structuring. Vent food webs did not appear to be Ridge in the north-east Pacific host dense populations of organised through predator–prey relationships. For example, Ridgeia piscesae tubeworms that promote habitat hetero- although trophic structure complexity increased with ecolog- geneity and local diversity. A detailed description of the ical successional stages, showing a higher number of preda- biodiversity and community structure is needed to help un- tors in the last stages, the food web structure itself did not derstand the ecological processes that underlie the distribu- change across assemblages.
    [Show full text]
  • Causes of Sea Level Rise
    FACT SHEET Causes of Sea OUR COASTAL COMMUNITIES AT RISK Level Rise What the Science Tells Us HIGHLIGHTS From the rocky shoreline of Maine to the busy trading port of New Orleans, from Roughly a third of the nation’s population historic Golden Gate Park in San Francisco to the golden sands of Miami Beach, lives in coastal counties. Several million our coasts are an integral part of American life. Where the sea meets land sit some of our most densely populated cities, most popular tourist destinations, bountiful of those live at elevations that could be fisheries, unique natural landscapes, strategic military bases, financial centers, and flooded by rising seas this century, scientific beaches and boardwalks where memories are created. Yet many of these iconic projections show. These cities and towns— places face a growing risk from sea level rise. home to tourist destinations, fisheries, Global sea level is rising—and at an accelerating rate—largely in response to natural landscapes, military bases, financial global warming. The global average rise has been about eight inches since the centers, and beaches and boardwalks— Industrial Revolution. However, many U.S. cities have seen much higher increases in sea level (NOAA 2012a; NOAA 2012b). Portions of the East and Gulf coasts face a growing risk from sea level rise. have faced some of the world’s fastest rates of sea level rise (NOAA 2012b). These trends have contributed to loss of life, billions of dollars in damage to coastal The choices we make today are critical property and infrastructure, massive taxpayer funding for recovery and rebuild- to protecting coastal communities.
    [Show full text]
  • Ocean Ridge Hydrothermal Vent Fluids Alison Marie Bray University of New Hampshire, Durham
    University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Winter 2001 The geochemistry of boron and lithium in mid - ocean ridge hydrothermal vent fluids Alison Marie Bray University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation Bray, Alison Marie, "The eg ochemistry of boron and lithium in mid -ocean ridge hydrothermal vent fluids" (2001). Doctoral Dissertations. 46. https://scholars.unh.edu/dissertation/46 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. NOTE TO USERS This reproduction is the best copy available. __ ® UMI Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. THE GEOCHEMISTRY OF BORON AND LITHIUM IN MID-OCEAN RIDGE HYDROTHERMAL VENT FLUIDS by Alison Marie Bray Bachelor of Arts, University of San Diego, 1995 Master of Science, University of New Hampshire, 1998 Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy In Earth Sciences December 2001 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 3030597 ___ ® UMI UMI Microform 3030597 Copyright 2002 by Bell & Howell Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code.
    [Show full text]
  • An Estimate of Hydrothermal Fluid Residence Times and Vent Chimney
    Earth and Planetary Science Letters, 76 (1985/86) 35-44 35 Elsevier Science Publishers B.V., Amsterdam Printed in The Netherlands [6] An estimate of hydrothermal fluid residence times and vent chimney growth rates based on 210 Pb/Pb ratios and mineralogic studies of sulfides dredged from the Juan de Fuca Ridge David Kadko ~, Randolph Koski 2 Mitsunobu Tatsumoto 3 and Robin Bouse 2 i College of Oceanograpt~v, Oregon State Unieersio,, Cort,allis, OR 97331 (U.S.A.) : U.S. Geological Survey, 345 3~iiddlefield Road, Menlo Park, CA 94025 (U.S.A.) -~ U.S. Geological Survey, Denver. CO 80225 (U.S.A.) Received January 22, 1985; revised version received August 26, 1985 The 2u~Pb/Pb ratios across two sulfide samples dredged from the Juan de Fuca Ridge are used to estimate the growth rate of the sulfide material and the residence time of the hydrothermal fluid within the oceanic crust from the onset of basalt alteration. 21°Pb is added to the hydrothermal fluid by two processes: (1) high-temperature alteration of basalt and (2) if the residence time of the fluid is on the order of the 22.3-year half-life of 210 Pb, by in-situ growth from 222 Rn (Krishnaswami and Turekian, 1982). Stable lead is derived only from the alteration of basalt. The 21°Pb/Pb ratio across one sample was - 0.5 dpm/10 6 g Pb, and across the other it was - 0.4 dpm/10 6 g Pb. These values are quite close to the 23SU/Pb ratios of basalts from the area, suggesting that the residence time of the hydrothermal fluid from the onset of basalt alteration is appreciably less than the mean life of 21°pb.
    [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]
  • Structure and Distribution of Cold Seep Communities Along the Peruvian Active Margin: Relationship to Geological and Fluid Patterns
    MARINE ECOLOGY PROGRESS SERIES Vol. 132: 109-125, 1996 Published February 29 Mar Ecol Prog Ser l Structure and distribution of cold seep communities along the Peruvian active margin: relationship to geological and fluid patterns 'Laboratoire Ecologie Abyssale, DROIEP, IFREMER Centre de Brest, BP 70, F-29280 Plouzane, France '~epartementdes Sciences de la Terre, UBO, 6 ave. Le Gorgeu, F-29287 Brest cedex, France 3~aboratoireEnvironnements Sedimentaires, DROIGM, IFREMER Centre de Brest, BP 70, F-29280 Plouzane, France "niversite P. et M. Curie, Observatoire Oceanologique de Banyuls, F-66650 Banyuls-sur-Mer, France ABSTRACT Exploration of the northern Peruvian subduction zone with the French submersible 'Nau- tile' has revealed benthlc communities dominated by new species of vesicomyid bivalves (Calyptogena spp and Ves~comyasp ) sustained by methane-nch fluid expulsion all along the continental margin, between depths of 5140 and 2630 m Videoscoplc studies of 25 dives ('Nautiperc cruise 1991) allowed us to describe the distribution of these biological conlnlunities at different spahal scales At large scale the communities are associated with fluid expuls~onalong the major tectonic features (scarps, canyons) of the margln At a smaller scale on the scarps, the distribuhon of the communities appears to be con- trolled by fluid expulsion along local fracturatlon features such as joints, faults and small-scale scars Elght dlves were made at one particular geological structure the Middle Slope Scarp (the scar of a large debns avalanche) where numerous
    [Show full text]