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The Official Magazine of The OceTHE OFFICIALa MAGAZINEn ogOF THE OCEANOGRAPHYra SOCIETYphy CITATION Hammond, S.R., R.W. Embley, and E.T. Baker. 2015. The NOAA Vents Program 1983 to 2013: Thirty years of ocean exploration and research. Oceanography 28(1):160–173, http://dx.doi.org/ 10.5670/ oceanog.2015.17. DOI http://dx.doi.org/ 10.5670/ oceanog.2015.17 COPYRIGHT This article has been published in Oceanography, Volume 28, Number 1, a quarterly journal of The Oceanography Society. Copyright 2015 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 REGULAR ISSUE FEATURE 1st 3D plume surveys Gorda Ridge eruption detected over a ridge 1st submarine 1st event Mariana Arc: 1st Ocean Exploration cruise Vents becomes 1986 Cleft 1st EPR eruption plume Earth-Ocean 1st US civilian eruption plume detected tracked 1st arc CO2 vents found 1st back-arc Interactions/ multibeam use verified survey (CoAxial) by float plume survey at NW Eifuku eruption detected Acoustics 1980 1985 1990 1995 2000 2005 2010 2015 1st forcast submarine Vents Megaplume (event Earth- MAPR 1st instrumented submarine 1st deep-sea eruption (Axial Smt.) Program plume) discovery quake program eruption (Axial Smt.) eruption begins monitoring begins observed in situ Ongoing submarine boninite begins NeMO begins eruption discovered 1st Juan de Fuca Ridge 1st Autonomous hydrophone side-scan/plume survey 1st quantification of gas flux The arrays deployed from a submarine volcano NOAA Vents Program 1983 to 2013 Thirty Years of Ocean Exploration and Research By Stephen R. Hammond, Robert W. Embley, and Edward T. Baker Eruption of Hades vent, West Mata seamount, taken by Jason remotely operated vehicle in 2009. 160 Oceanography | Vol.28, No.1 1st 3D plume surveys Gorda Ridge eruption detected over a ridge 1st submarine 1st event Mariana Arc: 1st Ocean Exploration cruise Vents becomes 1986 Cleft 1st EPR eruption plume Earth-Ocean 1st US civilian eruption plume detected tracked 1st arc CO2 vents found 1st back-arc Interactions/ multibeam use verified survey (CoAxial) by float plume survey at NW Eifuku eruption detected Acoustics 1980 1985 1990 1995 2000 2005 2010 2015 1st forcast submarine Vents Megaplume (event Earth- MAPR 1st instrumented submarine 1st deep-sea eruption (Axial Smt.) Program plume) discovery quake program eruption (Axial Smt.) eruption begins monitoring begins observed in situ Ongoing submarine boninite begins NeMO begins eruption discovered 1st Juan de Fuca Ridge 1st Autonomous hydrophone side-scan/plume survey 1st quantification of gas flux arrays deployed from a submarine volcano ABSTRACT. Two seminal advances in the late 1970s in science and technology spurred non-classified multibeam bathymetric the establishment of the National Oceanic and Atmospheric Administration (NOAA) sonar on the Surveyor, one of NOAA’s Vents Program: the unexpected discovery of seafloor vents and chemosynthetic global-class research vessels. In 1980, ecosystems on the Galápagos Spreading Center (GSC), and civilian access to a previously NOAA’s National Ocean Survey (now classified multibeam mapping sonar system. A small team of NOAA scientists Service) began the first systematic, immediately embarked on an effort to apply the new mapping technology to the high-resolution bathymetric mapping of discovery of vents, animal communities, and polymetallic sulfide deposits on spreading seafloor spreading centers. At NOAA’s ridges in the Northeast Pacific Ocean. The addition of interdisciplinary colleagues Pacific Marine Environmental Laboratory from NOAA’s cooperative institutes at Oregon State University and the University (PMEL), interest in the Northeast Pacific of Washington led to the creation of the Vents Program in 1983 at NOAA’s Pacific ridges began with cruises of opportunity in Marine Environmental Laboratory. Within a decade, Vents surveyed the entire Juan 1980–1983 that mapped ridge axial mor- de Fuca and Gorda Ridges for hydrothermal activity, discovered the first “megaplume,” phology, petrology, and tectonic features established multiyear time series of hydrothermal fluid measurements, and, for the first (Malahoff et al., 1982; Fornari et al., 1983) time, acoustically detected and responded to a deep-sea volcanic eruption. With this and found evidence of hydrothermal vent- experience, and partnering with researchers from around the globe, Vents expanded ing in near-bottom waters (Massoth et al., to exploration along the East Pacific and GSC divergent plate boundaries. In 1999, 1982) over the Juan de Fuca and Gorda the Vents Program embarked on systematic surveys along volcanic arcs and back- Ridges (Figure 2). During a span of five arc basins of the Mariana and Kermadec-Tonga subduction zones. For three decades, years, NOAA systematically mapped the the Vents Program focused on understanding the physical, chemical, and biological Northeast Pacific ridges and their inter- environmental consequences of global-scale processes that regulate the transfer of heat vening fracture zones (e.g., Malahoff et al., and mass from Earth’s hot interior into the ocean. As the fourth decade began, the 1981). Relative to the best maps previously Vents Program was restructured into two new programs, Earth-Ocean Interactions and available, the new maps revealed intrigu- Acoustics, that together continue, and broaden, the scope of Vents’ pioneering ocean ing structural complexities. The spread- exploration and research. ing ridges were revealed as a series of off- set segments, and the fracture zones were INTRODUCTION an entirely unanticipated discipline. The found to have a multiplicity of fault zones The 1977 discovery of deep-sea hydro- GSC discoveries, along with the discov- and en echelon pull-apart basins. One of thermal venting and its associated ani- ery of “black smokers” on the East Pacific the most interesting discoveries was that mal communities (Corliss et al., 1979) Rise (EPR) in 1979, quickly became the of an 8 km × 3 km caldera at the summit changed, in a moment, the relationship impetus for collaborative national and of the large volcano that dominates one between researchers and the ocean floor. international studies of spreading centers of the four segments of the Juan de Fuca Before this discovery at the Galápagos throughout the world ocean, an excite- Ridge (JdFR). Now familiarly known as Spreading Center (GSC), marine geol- ment that continues unabated today Axial Seamount, it is the youngest in a ogists and chemists focused predomi- (Figure 1). In this article, we trace the string of large submarine volcanoes, the nantly on questions of broad spatial and three-decade development and impact of Cobb-Eickelberg Seamount Chain, which temporal scale: plate movements, crustal one program whose work spans almost extends westward onto the Pacific plate. properties, and sediment geochemis- the entire history of seafloor hydrother- In 1982, a collaborative expedition try. Within the span of a research cruise, mal discovery and research. between NOAA and academic research- the deep sea acquired a human dimen- Nearly concurrent with the GSC dis- ers surveyed the JdFR using a new deep- sion. Fundamental geological and bio- coveries, the National Oceanic and towed digital 30 kHz side-scan sonar logical processes could be studied during Atmospheric Administration (NOAA) system (Crane et al., 1985). Thermistor the range and duration of a single sub- and the Office of Naval Research had arrays suspended below the side-scan mersible dive. Marine biologists founded the prescience to install the first US unit detected several hydrothermal Oceanography | March 2015 161 plumes along the ridge. This and other such as iron and sulfur compounds, included appreciable quantities of more information (e.g., Normark et al., 1982) global tracers such as 3He, and biolog- valuable elements, such as gold and silver. enabled discoveries of active hydrother- ically important gases such as carbon These discoveries provided an unam- mal systems along each of the surveyed dioxide (CO2), methane, and hydro- biguous opportunity for NOAA, estab- JdFR segments during the first Alvin sub- gen. Widespread scientific attention was lished with the overarching goal of being mersible dives in the Northeast Pacific in immediately focused on the chemosyn- the United States stewardship agency for 1984 (Figure 2). thetically and microbially sustained eco- Earth’s ocean. This responsibility requires systems that live exclusively in proximity an understanding of natural ocean pro- ESTABLISHING THE NOAA to both the warm and hot chemical-rich cesses and their effects on marine life and VENTS PROGRAM hydrothermal vent fluids. Another prom- resources, both biological and mineralog- Initial studies of the hydrothermal vent inent early interest in hydrothermal vents ical. Consequently, in 1983, NOAA estab- fluids sampled at the GSC and the EPR was the mineral resource potential of the lished the interdisciplinary team of ocean concluded that those discharges must often spectacular chimney-like structures scientists that soon became known as be pervasive along the global network and mounds that form when dissolved
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