Igneous, Alteration and Exhumation Processes Recorded in Abyssal Peridotites and Related Fault Rocks from an Oceanic Core Complex along the Central Indian Ridge

This paper presents the first detailed studies on the petrology of abyssal peridotites and related fault rocks recovered from an oceanic core complex (OCC) in the southern part of the Central Indian Ridge using the submersible SHINKAI 6500 of theJapan Agency for Marine^Earth Science andTechnology. Less deformed, statically serpentinized peridotites were recovered from the ridge-facing slope, whereas highly deformed rocks were recovered from sheet-like structures on the top surface of the OCC.The top surface of the OCC is interpreted to be the main detachment fault.The serpentinized peridotites are consistent with an origin as residues after moderate degrees (13^15%) of partial melting; these were later chemically modified as a result of the infiltration of evolved melts of probable granitic composition resulting in the formation of leucocratic veins. The deformed rocks from the detachment fault are divided into talc-rich and chlorite-rich parts, probably formed as a result of interaction of hydrothermal fluids with peridotite and gabbro precursors along the detachment fault, respectively. Deformation and alteration were locally concentrated along the detachment fault, resulting in mechanical mixing of both altered gabbros and serpentinized peridotites in the deformed rocks during the exhumation of the OCC associated with long-lived fault activity. Our results reveal that gabbros and peridotites are tectonically exposed in oceanic core complexes on the seafloor along the intermediate-spreading CIR, as well as in slow-spreading regions. Fluid-mobile elements such as Li, Rb, Ba, Pb, Sr and U are higher in serpentines than their precursor mantle minerals.The uranium content in serpentine is variable but is abundant in the outermost margin of the precursor minerals.The trace element compositions of serpentine appear to have been continuously

[1]  A. Tamura,et al.  Geochemical characteristics of chloritization of mafic crust from the northern Oman ophiolite: Implications for estimating the chemical budget of hydrothermal alteration of the oceanic lithosphere , 2009 .

[2]  W. Bach,et al.  Formation and alteration of plagiogranites in an ultramafic-hosted detachment fault at the Mid-Atlantic Ridge (ODP Leg 209) , 2009 .

[3]  Kentaro Nakamura,et al.  Serpentinized troctolites exposed near the Kairei Hydrothermal Field, Central Indian Ridge: Insights into the origin of the Kairei hydrothermal fluid supporting a unique microbial ecosystem , 2009 .

[4]  T. Mernagh,et al.  Distinguishing magmatic zircon from hydrothermal zircon: A case study from the Gidginbung high-sulphidation Au–Ag–(Cu) deposit, SE Australia , 2009 .

[5]  Ken Takai,et al.  Geological background of the Kairei and Edmond hydrothermal fields along the Central Indian Ridge: Implications of their vent fluids’ distinct chemistry , 2008 .

[6]  K. Michibayashi,et al.  Shearing within lower crust during progressive retrogression: Structural analysis of gabbroic rocks from the Godzilla Mullion, an oceanic core complex in the Parece Vela backarc basin , 2008 .

[7]  E. Condliffe,et al.  The Formation of Micro-Rodingites from IODP Hole U1309D: Key To Understanding the Process of Serpentinization , 2008 .

[8]  A. Tamura,et al.  Petrology and geochemistry of peridotites from IODP Site U1309 at Atlantis Massif, MAR 30°N: micro- and macro-scale melt penetrations into peridotites , 2008 .

[9]  Y. Lagabrielle,et al.  Geochemistry of the highly depleted peridotites drilled at ODP Sites 1272 and 1274 (Fifteen-Twenty Fracture Zone, Mid-Atlantic Ridge): Implications for mantle dynamics beneath a slow spreading ridge , 2008 .

[10]  B. Reynard,et al.  High-Pressure Creep of Serpentine, Interseismic Deformation, and Initiation of Subduction , 2007, Science.

[11]  T. Morishita,et al.  Petrology of local concentration of chromian spinel in dunite from the slow-spreading Southwest Indian Ridge , 2007 .

[12]  E. Deloule,et al.  Hydrothermal zircons : A tool for ion microprobe U-Pb dating of gold mineralization (Tamlalt - Menhouhou gold deposit - Morocco) , 2007 .

[13]  I. Savov,et al.  Shallow slab fluid release across and along the Mariana arc-basin system: Insights from geochemistry of serpentinized peridotites from the Mariana fore arc , 2007 .

[14]  Kentaro Nakamura,et al.  A new geochemical approach for constraining a marine redox condition of Early Archean , 2007 .

[15]  P. Kelemen,et al.  Trace element chemistry of zircons from oceanic crust: A method for distinguishing detrital zircon provenance , 2007 .

[16]  B. Frost,et al.  On Silica Activity and Serpentinization , 2007 .

[17]  E. Watson,et al.  New thermodynamic models and revised calibrations for the Ti-in-zircon and Zr-in-rutile thermometers , 2007 .

[18]  Kentaro Nakamura,et al.  Discovery of lanthanide tetrad effect in an oceanic plagiogranite from an Ocean Core Complex at the Central Indian Ridge 25°S , 2007 .

[19]  Kentaro Nakamura,et al.  Ultramafics-Hydrothermalism-Hydrogenesis-HyperSLiME (UltraH3) linkage: a key insight into early microbial ecosystem in the Archean deep-sea hydrothermal systems , 2006 .

[20]  D. Miller,et al.  Oceanic Core Complexes and Crustal Accretion at Slow-Spreading Ridges. Indications From IODP Expeditions 304-305 and Previous Ocean Drilling Results , 2006 .

[21]  H. Dick,et al.  Past and Future Impact of Deep Drilling in the Oceanic Crust and Mantle , 2006 .

[22]  H. Paulick,et al.  Geochemistry of abyssal peridotites (Mid-Atlantic Ridge, 15°20'N, ODP Leg 209): Implications for fluid/rock interaction in slow spreading environments , 2006 .

[23]  J. Lorand,et al.  Pervasive melt percolation reactions in ultra-depleted refractory harzburgites at the Mid-Atlantic Ridge, 15° 20′N: ODP Hole 1274A , 2006, Contributions to Mineralogy and Petrology.

[24]  K. Kunze,et al.  Semi-brittle flow during dehydration of lizardite–chrysotile serpentinite deformed in torsion: Implications for the rheology of oceanic lithosphere , 2006 .

[25]  Deborah K. Smith,et al.  Widespread active detachment faulting and core complex formation near 13° N on the Mid-Atlantic Ridge , 2006, Nature.

[26]  D. Kelley,et al.  Formation and evolution of carbonate chimneys at the Lost City Hydrothermal Field , 2006 .

[27]  H. Paulick,et al.  Unraveling the sequence of serpentinization reactions: petrography, mineral chemistry, and petrophysics of serpentinites from MAR 15°N (ODP Leg 209, Site 1274) , 2006 .

[28]  K. V. Von Damm,et al.  Geochemical controls on hydrothermal fluids from the Kairei and Edmond Vent Fields, 23°–25°S, Central Indian Ridge , 2006 .

[29]  E. Bonatti,et al.  Discontinuous Melt Extraction and Weak Refertilization of Mantle Peridotites at the Vema Lithospheric Section (Mid-Atlantic Ridge) , 2006 .

[30]  Javier Escartin,et al.  OCCURRENCE AND SIGNIFICANCE OF SERPENTINITE-HOSTED, TALC- AND AMPHIBOLE-RICH FAULT ROCKS IN MODERN OCEANIC SETTINGS AND OPHIOLITE COMPLEXES: AN OVERVIEW , 2006 .

[31]  P. Spadea,et al.  PETROGENESIS OF MANTLE PERIDOTITES FROM THE IZU-BONIN-MARIANA (IBM) FOREARC , 2006 .

[32]  Deborah S. Kelley,et al.  Mass transfer and fluid flow during detachment faulting and development of an oceanic core complex, Atlantis Massif (MAR 30°N) , 2006 .

[33]  T. Pettke,et al.  Magmatic-to-hydrothermal crystallization in the W–Sn mineralized Mole Granite (NSW, Australia): Part II: Evolving zircon and thorite trace element chemistry , 2005 .

[34]  T. M. Harrison,et al.  Zircon Thermometer Reveals Minimum Melting Conditions on Earliest Earth , 2005, Science.

[35]  Katherine A. Kelley,et al.  Geochemistry of serpentinized peridotites from the Mariana Forearc Conical Seamount, ODP Leg 125: Implications for the elemental recycling at subduction zones , 2005 .

[36]  Dana R. Yoerger,et al.  A Serpentinite-Hosted Ecosystem: The Lost City Hydrothermal Field , 2005, Science.

[37]  T. Morishita,et al.  Determination of Multiple Trace Element Compositions in Thin (> 30 μm) Layers of NIST SRM 614 and 616 Using Laser Ablation‐Inductively Coupled Plasma‐Mass Spectrometry (LA‐ICP‐MS) , 2005 .

[38]  P. Hoskin.  Trace-element composition of hydrothermal zircon and the alteration of Hadean zircon from the Jack Hills, Australia , 2005 .

[39]  Y. Niu.  Bulk-rock Major and Trace Element Compositions of Abyssal Peridotites: Implications for Mantle Melting, Melt Extraction and Post-melting Processes Beneath Mid-Ocean Ridges , 2004 .

[40]  K. Okino,et al.  Development of oceanic detachment and asymmetric spreading at the Australian‐Antarctic Discordance , 2004 .

[41]  Kentaro Nakamura,et al.  Carbonatization of oceanic crust by the seafloor hydrothermal activity and its significance as a CO2 sink in the Early Archean , 2004 .

[42]  B. John,et al.  Strain localization on an oceanic detachment fault system, Atlantis Massif, 30°N, Mid‐Atlantic Ridge , 2004 .

[43]  A. Woodland,et al.  Varying behaviour of Li in metasomatised spinel peridotite xenoliths from western Victoria, Australia , 2004 .

[44]  B. W. Evans.  The Serpentinite Multisystem Revisited: Chrysotile Is Metastable , 2004 .

[45]  T. Morishita,et al.  Magmatic srilankite (Ti2ZrO6) in gabbroic vein cutting oceanic peridotites: An unusual product of peridotite-melt interactions beneath slow-spreading ridges , 2004 .

[46]  Koshi Yamamoto,et al.  Significance of Serpentinites and Related Rocks in the High-Pressure Metamorphic Terranes, Circum-Pacific Regions , 2004 .

[47]  K. Nejbert,et al.  U–Pb dating of serpentinization: hydrothermal zircon from a metasomatic rodingite shell (Sudetic ophiolite, SW Poland) , 2004 .

[48]  H. Paulick,et al.  Seawater‐peridotite interactions: First insights from ODP Leg 209, MAR 15°N , 2003 .

[49]  N. Kusznir,et al.  Mechanism for generating the anomalous uplift of oceanic core complexes: Atlantis Bank, southwest Indian Ridge , 2003 .

[50]  C. Mével.  Serpentinization of abyssal peridotites at mid-ocean ridges , 2003 .

[51]  J. Escartín,et al.  Constraints on deformation conditions and the origin of oceanic detachments: The Mid‐Atlantic Ridge core complex at 15°45′N , 2003 .

[52]  L. Parson,et al.  FUJI Dome: A large detachment fault near 64°E on the very slow‐spreading southwest Indian Ridge , 2003 .

[53]  D. Butterfield,et al.  30,000 Years of Hydrothermal Activity at the Lost City Vent Field , 2003, Science.

[54]  T. Morishita,et al.  Evolution of Low-Al Orthopyroxene in the Horoman Peridotite, Japan: an Unusual Indicator of Metasomatizing Fluids , 2003 .

[55]  L. Gasperini,et al.  Mantle thermal pulses below the Mid-Atlantic Ridge and temporal variations in the formation of oceanic lithosphere , 2003, Nature.

[56]  W. Seyfried,et al.  Compositional controls on vent fluids from ultramafic-hosted hydrothermal systems at mid-ocean ridges: An experimental study at 400°C, 500 bars , 2003 .

[57]  A. Poliakov,et al.  Modes of faulting at mid-ocean ridges , 2003, Nature.

[58]  M. Cannat,et al.  Evidence for major‐element heterogeneity in the mantle source of abyssal peridotites from the Southwest Indian Ridge (52° to 68°E) , 2003 .

[59]  U. Schaltegger,et al.  The Composition of Zircon and Igneous and Metamorphic Petrogenesis , 2003 .

[60]  P. Hoppe,et al.  Garnet-field melting and late-stage refertilization in "Residual" abyssal peridotites from the Central Indian Ridge , 2002 .

[61]  Deborah K. Smith,et al.  Direct geological evidence for oceanic detachment faulting: The Mid-Atlantic Ridge, 15°45′N , 2002 .

[62]  P. Tartarotti,et al.  Melt migration in the upper mantle along the Romanche Fracture Zone (Equatorial Atlantic) , 2002 .

[63]  H. Kopp,et al.  A rifted inside corner massif on the Mid-Atlantic Ridge at 5°S , 2002 .

[64]  E. Oelkers,et al.  The rainbow vent fluids (36°14′N, MAR): the influence of ultramafic rocks and phase separation on trace metal content in Mid-Atlantic Ridge hydrothermal fluids , 2002 .

[65]  L. Reisberg,et al.  Behavior of Li and its isotopes during serpentinization of oceanic peridotites , 2002 .

[66]  Kei Okamura,et al.  Chemical characteristics of newly discovered black smoker fluids and associated hydrothermal plumes at the Rodriguez Triple Junction, Central Indian Ridge , 2001 .

[67]  B. Evans,et al.  Strength of slightly serpentinized peridotites: Implications for the tectonics of oceanic lithosphere , 2001 .

[68]  M. Kinoshita,et al.  Submersible study of an oceanic megamullion in the central North Atlantic , 2001 .

[69]  Deborah S. Kelley,et al.  An off-axis hydrothermal vent field near the Mid-Atlantic Ridge at 30° N , 2001, Nature.

[70]  Toshiyuki Yamaguchi,et al.  First Hydrothermal Vent Communities from the Indian Ocean Discovered , 2001 .

[71]  A. Hofmann,et al.  Coupled major and trace elements as indicators of the extent of melting in mid-ocean-ridge peridotites , 2001, Nature.

[72]  D. Bideau,et al.  A long in situ section of the lower ocean crust: results of {ODP} Leg 176 drilling at the Southwest Indian Ridge , 2000 .

[73]  A. Woodland,et al.  The distribution of lithium in peridotitic and pyroxenitic mantle lithologies — an indicator of magmatic and metasomatic processes , 2000 .

[74]  R. Hékinian,et al.  Geochemistry of lavas from the Garrett Transform Fault: insights into mantle heterogeneity beneath the eastern Pacific , 1999 .

[75]  N. Clauer,et al.  Petrology, isotope geochemistry and chemical budgets of oceanic gabbros-seawater interactions in the Equatorial Atlantic , 1999 .

[76]  N. Mozgova,et al.  Mineralogy and chemistry of massive sulfides from the Logatchev hydrothermal field (14 degrees 45'N Mid-Atlantic Ridge) , 1999 .

[77]  M. Constantin.  Gabbroic intrusions and magmatic metasomatism in harzburgites from the Garrett transform fault: implications for the nature of the mantle–crust transition at fast-spreading ridges , 1999 .

[78]  Deborah K. Smith,et al.  Origin of extensional core complexes: Evidence from the Mid‐Atlantic Ridge at Atlantis Fracture Zone , 1998 .

[79]  J. Pearce,et al.  Peridotites from the Izu-Bonin-Mariana Forearc (ODP Leg 125): Evidence for Mantle Melting and Melt-Mantle Interaction in a Supra-Subduction Zone Setting , 1998 .

[80]  B. Hanan,et al.  Chaotic topography, mantle flow and mantle migration in the Australian–Antarctic discordance , 1998, Nature.

[81]  M. C. Kleinrock,et al.  Megamullions and mullion structure defining oceanic metamorphic core complexes on the Mid-Atlantic Ridge , 1998 .

[82]  C. Langmuir,et al.  The origin of abyssal peridotites: a new perspective , 1997 .

[83]  Y. Niu.  Mantle melting and melt extraction processes beneath ocean ridges : evidence from abyssal peridotites , 1997 .

[84]  S. Jackson,et al.  A Compilation of New and Published Major and Trace Element Data for NIST SRM 610 and NIST SRM 612 Glass Reference Materials , 1997 .

[85]  B. Evans,et al.  Nondilatant brittle deformation of serpentinites: Implications for Mohr-Coulomb theory and the strength of faults , 1997 .

[86]  R. Hékinian,et al.  Spreading-rate dependence of the extent of mantle melting beneath ocean ridges , 1997, Nature.

[87]  N. Shimizu,et al.  Open‐system melting in the upper mantle: Constraints from the Hayachine‐Miyamori ophiolite, northeastern Japan , 1995 .

[88]  H. Dick,et al.  Pervasive magnesium loss by marine weathering of peridotite , 1995 .

[89]  S. Hart,et al.  Nd and Sr isotope evidence linking mid-ocean-ridge basalts and abyssal peridotites , 1994, Nature.

[90]  Jian Lin,et al.  A geological model for the structure of ridge segments in slow spreading ocean crust , 1994 .

[91]  D. Elthon.  Chemical trends in abyssal peridotites : Refertilization of depleted suboceanic mantle , 1992 .

[92]  G. Udintsev,et al.  Upper mantle heterogeneity below the Mid-Atlantic Ridge, 0°–15°N , 1992 .

[93]  D. Bideau,et al.  Serpentinized peridotites and gabbros in the Mid-Atlantic Ridge axial valley at 15°37′N and 16°52′N , 1992 .

[94]  T. Köhler,et al.  Geothermobarometry in Four-phase Lherzolites II. New Thermobarometers, and Practical Assessment of Existing Thermobarometers , 1990 .

[95]  Richard G. Gordon,et al.  Current plate motions , 1990 .

[96]  H. Dick,et al.  Melting in the oceanic upper mantle: An ion microprobe study of diopsides in abyssal peridotites , 1990 .

[97]  A. Saunders,et al.  Magmatism in the Ocean Basins , 1989 .

[98]  D. C. Gerlach,et al.  Sr isotopic constraints on hydrothermal alteration of ultramafic rocks in two oceanic fracture zones from the South Atlantic Ocean , 1986 .

[99]  F. Spear,et al.  High temperature alteration of Abyssal ultramafics from the Islas Orcadas Fracture Zone, South Atlantic , 1985 .

[100]  H. Dick,et al.  Mineralogic variability of the uppermost mantle along mid-ocean ridges , 1984 .

[101]  A. Miyashiro,et al.  Metasomatic chloritization of gabbros in the Mid-Atlantic Ridge near 30°N , 1979 .

[102]  S. Hart,et al.  Uranium and boron distributions in some oceanic ultramafic rocks , 1973 .

[103]  M. Ewing,et al.  Composition and origin of serpentinites from the Mid-Atlantic Ridge near 24° and 30° North Latitude , 1969 .

[104]  N. J. Page.  Serpentinization Considered as a Constant Volume Metasomatic Process: A Discussion , 1967 .

[105]  B. Mason.  Composition of the Earth , 1966, Nature.

[106]  D. Yoerger,et al.  Hydrothermal Field A Serpentinite-Hosted Ecosystem : The Lost City , 2009 .

[107]  J. Koepke,et al.  The formation of SiO2-rich melts within the deep oceanic crust by hydrous partial melting of gabbros , 2007 .

[108]  T. Morishita,et al.  Simultaneous determination of multiple trace element compositions in thin (<30.MU.m) layers of BCR-2G by 193 nm ArF excimer laser ablation-ICP-MS: implications for matrix effect and elemental fractionation on quantitative analysis , 2005 .

[109]  M. D’Orazio,et al.  Talc-rich hydrothermal rocks from the St. Paul and Conrad fracture zones in the Atlantic Ocean , 2004 .

[110]  T. Morishita,et al.  Simultaneous in-situ multi-element analysis of minerals on thin section using LA-ICP-MS , 2004 .

[111]  J. Koepke,et al.  Petrogenesis of oceanic plagiogranites by partial melting of gabbros: an experimental study , 2004 .

[112]  W. Bach,et al.  Mineral chemistry, whole-rock compositions, and petrogenesis of leg 176 gabbros: Data and discussion , 2002 .

[113]  Zhang Guang-wei,et al.  AN OFF-AXIS HYDROTHERMAL VENT FIELD NEAR THE MID-ATLANTIC RIDGE AT 30°N , 2002 .

[114]  A. Klaus,et al.  Proceedings of the Ocean Drilling Program, Scientific Results , 2001 .

[115]  Y. Ohara,et al.  Giant Megamullion in the Parece Vela Backarc Basin , 2001 .

[116]  R. Hékinian,et al.  Basaltic liquids and harzburgitic residues in the Garrett Transform: a case study at fast-spreading ridges , 1997 .

[117]  S. Arai.  Petrology of the gabbro-troctolite-peridotite complex from Hess Deep, equatorial Pacific : Implications for mantle-melt interaction within the oceanic lithosphere , 1996 .

[118]  D. Günther,et al.  Inter-laboratory note. Laser ablation inductively coupled plasma mass spectrometric transient signal data acquisition and analyte concentration calculation , 1996 .

[119]  D. S. O'Hanley.  Serpentinites : records of tectonic and petrological history , 1996 .

[120]  John F. Casey,et al.  An Ultramafic Lift at the Mid-Atlantic Ridge: Successive Stages of Magmatism in Serpentinized Peridotites from the 15°N Region , 1995 .

[121]  M. Cannat,et al.  Gabbroic Dikelets in Serpentinized Peridotites from the Mid-Atlantic Ridge at 23°20’N , 1995 .

[122]  J. Reynolds,et al.  Thin crust, ultramafic exposures, and rugged faulting patterns at the Mid-Atlantic Ridge (22°–24°N) , 1995 .

[123]  R. Vissers,et al.  Mantle and lower crust exposed in oceanic ridges and in ophiolites : contributions to a specialized symposium of the VII [sic] EUG Meeting, Strasbourg, spring 1993 , 1995 .

[124]  R. Berry,et al.  High-pressure experimental calibration of the olivine-orthopyroxene-spinel oxygen geobarometer: implications for the oxidation state of the upper mantle , 1994 .

[125]  R. Berry,et al.  High pressure experimental calibration of the olivine-orthopyroxene-spinel oxygen geobarometer: implications for the oxidation state of the upper mantle , 1991 .

[126]  A. Masuda,et al.  Lanthanide tetrad effect observed in leucogranites from China , 1989 .

[127]  H. Dick.  Abyssal peridotites, very slow spreading ridges and ocean ridge magmatism , 1989, Geological Society, London, Special Publications.

[128]  A. Masuda,et al.  Lanthanide tetrad effects in nature: two mutually opposite types, W and M , 1987 .

[129]  B. Frost.  Contact Metamorphism of Serpentinite, Chloritic Blackwall and Rodingite at Paddy-Go-Easy Pass, Central Cascades, Washington , 1975 .