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THE OFFICIAL Magazine of the OCEANOGRAPHY SOCIETY OceThe Officiala MaganZineog of the Oceanographyra Spocietyhy CITATION Fornari, D.J., S.E. Beaulieu, J.F. Holden, L.S. Mullineaux, and M. Tolstoy. 2012. Introduction to the special issue: From RIDGE to Ridge 2000. Oceanography 25(1):12–17, http://dx.doi.org/10.5670/ oceanog.2012.01. DOI http://dx.doi.org/10.5670/oceanog.2012.01 COPYRIGHT This article has been published inOceanography , Volume 25, Number 1, a quarterly journal of The Oceanography Society. Copyright 2012 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://WWW.tos.org/oceanography OCEANIC SPreAding CenTer ProCesses | Ridge 2000 ProgrAM ReseARCH Introduction to the Special Issue From RIDGE to Ridge 2000 BY DAnieL J. FornAri, STACE E. BEAULieU, JAMes F. HoLden, LAUren S. MULLineAUX, And MAYA ToLSTOY Articles in this special issue of the following quote from H.H. Hess nature of volcanically-driven submarine Oceanography represent a compendium (1962) in his essay on “geopoetry” and hot springs and their attendant chemo- of research that spans the disciplinary commentary on J.H.F. Umbgrove’s synthetically-based animal communities and thematic breadth of the National (1947) comprehensive summary of Earth underscore the fact that the seafloor/ Science Foundation’s Ridge 2000 and ocean history: ridge crest environment represents one Program, as well as its geographic focal The birth of the oceans is a matter of of the current frontiers in the explora- points. The mid-ocean ridge (MOR) conjecture, the subsequent history is tion and understanding of our planet. crest is where much of Earth’s volcanism obscure, and the present structure is just The global spreading center network may is focused and where most submarine beginning to be understood. Fascinating be viewed as a single system of focused volcanic activity occurs. If we could speculation on these subjects has been energy flow from the earth’s interior to the look down from space at our planet plentiful, but not much of it predating the lithosphere, hydrosphere and biosphere. with the ocean drained, the MOR’s last decade [the 1950s] holds water. Viewed in this manner it becomes evident topography and shape, along with that the processes involved in generation its intervening fracture zones, would The discovery of deep-sea hydro- of oceanic lithosphere are strongly inter- resemble the seams on a baseball, with thermal vents in the late 1970s, and connected and that an interdisciplinary the ocean basins dominating our plan- the overwhelming evidence that approach will be necessary to achieve etary panorama. The volcanic seafloor seafloor spreading and volcanism major strides in our understanding is hidden beneath the green-blue waters exerted fundamental controls on of the role lithosphere genesis plays of the world’s ocean, yet therein lie myriad Earth processes spanning the in planetary evolution. fundamental clues to how our planet geo- and biosciences, led to an Ocean works and has evolved over billions of Studies Board (1988) workshop that This statement, derived from the years, something that was not clearly reported the following: expansive deliberations of over 80 ocean understood 65 years ago—witness Recent discoveries of the widespread and Earth scientists immersed in the 12 Oceanography | Vol. 25, No. 1 early spring mists of Salishan Lodge associated with hydrothermal venting, animals; and exploration of the role of along the Oregon coast, served as including seafloor chimney distributions, larval dispersal in population dynamics the overarching unifying objective sulfide mineral and fluid chemistry, and maintenance. The results of these of the Ridge Interdisciplinary Global relationships to local- and regional-scale decade-long multidisciplinary efforts Experiments (RIDGE) Initiative funded volcanic and tectonic processes, and the on a wide range of field, laboratory, by the National Science Foundation’s physics and chemistry of hydrothermal and modeling studies laid the essential Ocean Sciences Division. That guiding plumes that carry the effluent into the groundwork for future MOR research. principle focused research efforts global hydrosphere. Biological objectives The RIDGE Program capitalized through the 1990s to explore all facets included a focus on chemoautotrophy on the use of new, innovative tech- of global MOR phenomena, yielding a and how it fuels deep communities at nologies, including both tethered and profound expansion of our knowledge of vents; characterization of diversity, gene autonomous robotic vehicle systems, oceanic spreading center processes. flow, and global distribution of vent as well as traditional human-occupied The RIDGE geographic purview species; investigation of metabolic and submersibles, and also improvements was global, with scientific imperatives physiological capabilities of microbes and in near-bottom sonar and imaging ranging from understanding mantle dynamics using a variety of geophysical Daniel J. Fornari ([email protected]) is Senior Scientist, Geology and Geophysics techniques and modeling, to along-strike Department, Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA, USA. characterization of MOR lava vari- Stace E. Beaulieu is Research Specialist, Biology Department, WHOI, Woods Hole, MA, ability and correlation to mantle melting USA. James F. Holden is Associate Professor, Department of Microbiology, University processes. A key RIDGE objective was to of Massachusetts, Amherst, MA, USA. Lauren S. Mullineaux is Senior Scientist, Biology better resolve the nature and influence Department, WHOI, Woods Hole, MA, USA. Maya Tolstoy is Associate Professor, of MOR segmentation and spreading- Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory of rate variability on a host of processes Columbia University, Palisades, NY, USA. Oceanography | March 2012 13 Figure 1. Locations of the three Ridge 2000 Integrated Study Sites plotted on the global bathymetric tile set available through Virtual Ocean (http:// www.virtualocean.org; Ryan et al., 2009). EPR = East Pacific Rise. END = Endeavour Segment of the Juan de Fuca Ridge. LAU = Eastern Lau Spreading Center. hardware and software that provided microbial processes and the techniques et al., 2009; http://www.marine-geo.org/ ever-increasing resolution of seafloor to study them. portals/ridge2000). The MOR commu- features and processes. During the During 2000–2002, the US oceano- nity chose three focus areas as Integrated Ridge 2000 Program, implementation graphic community gathered to evaluate Study Sites (ISSs) where coordinated and use of robotic and autonomous the RIDGE Program’s previous decade experiments would be conducted—the vehicles became routine, and a wide of findings and to outline priorities East Pacific Rise (EPR) from 8°N to range of new, specialized sensors and for the next decade. The Ridge 2000 11°N, the Endeavour Segment of the sampling devices were developed to Program formally began in 2002 with Juan de Fuca Ridge, and the Eastern Lau capture various physical and biogeo- new proposal solicitation guidelines Spreading Center (see Figure 1). chemical characteristics of hydrothermal for the types of research activities that The articles in this special issue of fluids. Much of the new technology would be the focus of the new program. Oceanography highlight the wealth of was designed to operate in situ, thereby The next steps required coordinated and interdisciplinary research on oceanic making the measurements more accurate focused studies that included exploring spreading centers accomplished over the and relevant to interactions between both temporal and spatial associations past decade of Ridge 2000 field, labora- vent macro- and microfauna and the among diverse processes involved in tory, and modeling studies. Many of the chemistry of fluids that bathe them. A the transfer of mantle-derived heat and articles were conceived during detailed significant development during the past chemical energy to the seafloor and into discussions in various working groups few decades of spreading-center research the biosphere through hydrothermal at the Ridge 2000 meeting in Portland, was the first recognition of the associa- circulation. Part of this effort involved Oregon, in 2010, and in follow-up efforts tion between H2, S, and Fe oxidizing a dedicated approach toward data and since then (see Rubin and Fornari, 2011). microbes and seafloor volcanic erup- metadata archiving and accessibility in These research endeavors represent tions, which led to an explosion in the order to facilitate and enhance scientific not an “end” but rather a beginning of recognition and importance of deep-sea discovery (Carbotte et al., 2004; Ryan a vibrant next phase of global research 14 Oceanography | Vol. 25, No. 1 on oceanic spreading centers that Program, we chose to start the research for the last 60 years. Two articles, will continue to explore myriad links review articles with the geophysics and by Carbotte et al. and Canales et al., between causal processes in both spatial petrology of the lithosphere. Gregg present some of the latest results from and temporal
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