The Effect of Arc Proximity on Hydrothermal Activity Along Spreading Centers: New Evidence From the Mariana Back Arc (12.7°N–18.3°N)

Back‐arc spreading centers (BASCs) form a distinct class of ocean spreading ridges distinguished by steep along‐axis gradients in spreading rate and by additional magma supplied through subduction. These characteristics can affect the population and distribution of hydrothermal activity on BASCs compared to mid‐ocean ridges (MORs). To investigate this hypothesis, we comprehensively explored 600 km of the southern half of the Mariana BASC. We used water column mapping and seafloor imaging to identify 19 active vent sites, an increase of 13 over the current listing in the InterRidge Database (IRDB), on the bathymetric highs of 7 of the 11 segments. We identified both high and low (i.e., characterized by a weak or negligible particle plume) temperature discharge occurring on segment types spanning dominantly magmatic to dominantly tectonic. Active sites are concentrated on the two southernmost segments, where distance to the adjacent arc is shortest (<40 km), spreading rate is highest (>48 mm/yr), and tectonic extension is pervasive. Re‐examination of hydrothermal data from other BASCs supports the generalization that hydrothermal site density increases on segments <90 km from an adjacent arc. Although exploration quality varies greatly among BASCs, present data suggest that, for a given spreading rate, the mean spatial density of hydrothermal activity varies little between MORs and BASCs. The present global database, however, may be misleading. On both BASCs and MORs, the spatial density of hydrothermal sites mapped by high‐quality water‐column surveys is 2–7 times greater than predicted by the existing IRDB trend of site density versus spreading rate.

[1]  E. Baker,et al.  A Recent Volcanic Eruption Discovered on the Central Mariana Back-Arc Spreading Center , 2018, Front. Earth Sci..

[2]  J. Woodhead,et al.  Asthenospheric outflow from the shrinking Philippine Sea Plate: Evidence from Hf–Nd isotopes of southern Mariana lavas , 2017 .

[3]  E. Baker,et al.  Geological interpretation of volcanism and segmentation of the Mariana back‐arc spreading center between 12.7°N and 18.3°N , 2017 .

[4]  Katherine A. Kelley,et al.  The Fina Nagu volcanic complex: Unusual submarine arc volcanism in the rapidly deforming southern Mariana margin , 2016 .

[5]  Fernando Martinez,et al.  How many vent fields? New estimates of vent field populations on ocean ridges from precise mapping of hydrothermal discharge locations , 2016 .

[6]  R. Arculus,et al.  The Fonualei Rift and Spreading Center: Effects of ultraslow spreading and arc proximity on back‐arc crustal accretion , 2016 .

[7]  E. Baker,et al.  Where are the undiscovered hydrothermal vents on oceanic spreading ridges , 2015 .

[8]  U. Tsunogai,et al.  Chemical composition of hydrothermal fluids in the central and southern Mariana Trough backarc basin , 2015 .

[9]  J. Escartín,et al.  Temporal variability and tidal modulation of hydrothermal exit‐fluid temperatures at the Lucky Strike deep‐sea vent field, Mid‐Atlantic Ridge , 2014 .

[10]  J. Lavelle,et al.  A turbulent convection model with an observational context for a deep‐sea hydrothermal plume in a time‐variable cross flow , 2013 .

[11]  Kentaro Nakamura,et al.  Discovery of a new hydrothermal vent based on an underwater, high-resolution geophysical survey , 2013 .

[12]  R. E. McDuff.  Physical Dynamics of Deep-Sea Hydrothermal Plumes , 2013 .

[13]  Y. Tamura,et al.  How the Mariana Volcanic Arc ends in the south , 2013 .

[14]  M. Hannington,et al.  Tectonic and magmatic controls on hydrothermal activity in the Woodlark Basin , 2012 .

[15]  K. Okino,et al.  Geomorphological variations at hydrothermal sites in the southern Mariana Trough: Relationship between hydrothermal activity and topographic characteristics , 2012 .

[16]  Kenneth H. Rubin,et al.  Unique event plumes from a 2008 eruption on the Northeast Lau Spreading Center , 2011 .

[17]  R. Dunn,et al.  Contrasting crustal production and rapid mantle transitions beneath back-arc ridges , 2011, Nature.

[18]  E. Baker,et al.  Microbial carbon isotope fractionation to produce extraordinarily heavy methane in aging hydrothermal plumes over the southwestern Okinawa Trough , 2010 .

[19]  E. Baker,et al.  Chemistry of hydrothermal plumes above submarine volcanoes of the Mariana Arc , 2009 .

[20]  E. Baker,et al.  Regional Venting in the Manus Basin, New Britain Back Arc , 2008 .

[21]  M. Utsumi,et al.  Geochemistry of Sulfide Chimneys and Basement Pillow Lavas at the Southern Mariana Trough (12.55°N–12.58°N) , 2008 .

[22]  E. Baker,et al.  A New Tool for Detecting Hydrothermal Plumes: an ORP Sensor for the PMEL MAPR , 2007 .

[23]  Katherine A. Kelley,et al.  Mantle melting as a function of water content beneath back-arc basins , 2006 .

[24]  L. Germanovich,et al.  The first measurements of hydrothermal heat output at 9°50′N, East Pacific Rise , 2006 .

[25]  E. Baker,et al.  Abundant hydrothermal venting along melt‐rich and melt‐free ridge segments in the Lau back‐arc basin , 2006 .

[26]  E. Baker,et al.  Hydrothermal activity on near‐arc sections of back‐arc ridges: Results from the Mariana Trough and Lau Basin , 2005 .

[27]  U. Tsunogai,et al.  Discovery of a new hydrothermal venting site in the southernmost Mariana Arc: Al-rich hydrothermal plumes and white smoker activity associated with biogenic methane , 2004 .

[28]  H. Kimura,et al.  Geochemistry of Hydrothermal Fluids in South Mariana Backarc Spreading Center , 2004 .

[29]  Teruyuki Kato,et al.  Geodetic evidence of back‐arc spreading in the Mariana Trough , 2003 .

[30]  B. Taylor,et al.  Back-arc basin basalt systematics , 2003 .

[31]  P. Bird.  An updated digital model of plate boundaries , 2003 .

[32]  S. Petersen,et al.  Discovery of new hydrothermal vent sites in Bransfield Strait, Antarctica , 2001 .

[33]  B. Taylor,et al.  A three‐plate kinematic model for Lau Basin opening , 2001 .

[34]  P. Tyler,et al.  Hydrothermal plumes above the East Scotia Ridge: an isolated high-latitude back-arc spreading centre , 2000 .

[35]  J. López-Martínez,et al.  Bransfield Basin, Antarctic Peninsula: Not a normal backarc basin , 2000 .

[36]  R. Binns,et al.  Anatomy of an Active, Felsic-Hosted Hydrothermal System, Eastern Manus Basin , 2000 .

[37]  E. Baker,et al.  The rise and fall of the Coaxial hydrothermal site, 1993–1996 , 1998 .

[38]  D. Barker,et al.  Distributed, active extension in Bransfield basin Antarctic Peninsula: Evidence from multibeam bathymetry , 1996 .

[39]  I. Wright,et al.  The Lau-Havre-Taupo back-arc basin: A southward-propagating, multi-stage evolution from rifting to spreading , 1996 .

[40]  A. Goodliffe,et al.  Continental rifting and initial sea-floor spreading in the Woodlark basin , 1995, Nature.

[41]  R. Hessler,et al.  Biogeography of Mariana Trough hydrothermal vent communities , 1991 .

[42]  P. Sedwick,et al.  Manganese and methane anomalies in the North Fiji Basin , 1990 .

[43]  Bramley J. Murton,et al.  Role of ridge jumps and ridge propagation in the tectonic evolution of the Lau back-arc basin, southwest Pacific , 1990 .

[44]  H. Craig,et al.  Hydrothermal methane plumes in the Mariana back-arc spreading centre , 1986, Nature.

[45]  M. Kimura,et al.  THE OKINAWA TROUGH: GENESIS OF A BACK-ARC BASIN DEVELOPING ALONG A CONTINENTAL MARGIN , 1986 .

[46]  J. R. Delaney,et al.  Entrainment and vertical transport of deep-ocean water by buoyant hydrothermal plumes , 1985, Nature.

[47]  R. Stern,et al.  Unzipping of the volcano arc, Japan , 1984 .

[48]  American Public Health Association , 1886, Buffalo medical and surgical journal.

[49]  Kentaro Nakamura,et al.  Chemical and Isotopic Compositions of Hydrothermal Fluids at Snail, Archaean, Pika, and Urashima Sites in the Southern Mariana Trough , 2015 .

[50]  E. Baker,et al.  Decay of hydrothermal output following the 1998 seafloor eruption at Axial Volcano: Observations and models , 2004 .

[51]  B. Taylor,et al.  Controls on back-arc crustal accretion: insights from the Lau, Manus and Mariana basins , 2003, Geological Society, London, Special Publications.

[52]  R. Livermore.  Back-arc spreading and mantle flow in the East Scotia Sea , 2003, Geological Society, London, Special Publications.

[53]  R. Larter,et al.  Intra-Oceanic Subduction Systems: Tectonic and Magmatic Processes , 2003 .

[54]  K. Mitsuzawa.  Preliminary report of Deep-Tow/Yokosuka Cruise at hydrothermal areas in the Mid and Southern Mariana , 2000 .

[55]  Awwa,et al.  Standard Methods for the examination of water and wastewater , 1999 .

[56]  Susan E. Humphris,et al.  Seafloor hydrothermal systems : physical, chemical, biological, and geological interactions , 1995 .

[57]  S. Eggins,et al.  Subduction zone magmatism , 1995 .

[58]  L. Parson,et al.  Geochemistry of Lau Basin volcanic rocks: influence of ridge segmentation and arc proximity , 1994, Geological Society, London, Special Publications.

[59]  B. Pelletier,et al.  Twin active spreading ridges in the North Fiji Basin (southwest Pacific) , 1994 .