Oceanography The Official Magazine of
The Oceanography Society
Volume 25 Issue 01

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Volume 25, No. 1
Pages 89 - 93

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Lava Geochemistry as a Probe into Crustal Formation at the East Pacific Rise

By Michael R. Perfit , V. Dorsey Wanless , W. Ian Ridley , Emily M. Klein, Matthew C. Smith, Adam R. Goss, Jillian S. Hinds, Scott W. Kutza, and Daniel J. Fornari  
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Basalt lavas comprise the greatest volume of volcanic rocks on Earth, and most of them erupt along the world’s mid-ocean ridges (MORs). These MOR basalts (MORBs) are generally thought to be relatively homogeneous in composition over large segments of the global ridge system (e.g., Klein, 2005). However, detailed sampling of two different regions on the northern East Pacific Rise (EPR) and extensive analysis of the samples show that fine-scale mapping and sampling of the ridge axis can reveal significant variations in lava chemistry on both small spatial and short temporal scales. The two most intensely sampled sites within the EPR Integrated Study Site (ISS) lie on and off axis between 9°17’N and 10°N, and from a wide region centered around 9°N where two segments of the EPR overlap (see Fornari et al., 2012, Figure 3, in this issue). The chemical composition of erupted lavas, similar to the genotype of an organism, can be used by igneous petrologists to trace the evolution of magmas from the mantle to the seafloor. The extensive and detailed geochemical studies at the EPR highlight how a thorough understanding of the variability in lava compositions on small spatial scales (i.e., between lava flows) and large spatial scales (i.e., from segment center to segment end and including discontinuities in the ridge crest) can be used in combination with seafloor photography, lava morphology, and bathymetry to provide insights into the magmatic system that drives volcanism and influences hydrothermal chemistry and biology at a fast-spreading MOR.

Citation

Perfit, M.R., V.D. Wanless, W.I. Ridley, E.M. Klein, M.C. Smith, A.R. Goss, J.S. Hinds, S.W. Kutza, and D.J. Fornari. 2012. Lava geochemistry as a probe into crustal formation at the East Pacific Rise. Oceanography 25(1):89–93, https://doi.org/10.5670/oceanog.2012.06.

References

Batiza, R., and Y. Niu. 1992. Petrology and magma chamber processes at the East Pacific Rise ~ 9°30’N. Journal of Geophysical Research 97:6,779–6,797, https://doi.org/10.1029/92JB00172.

Carbotte, S., and K. Macdonald. 1992. East Pacific Rise 8–10°30’N: Evolution of ridge segments and discontinuities from SeaMARC II and three-dimensional magnetic studies. Journal of Geophysical Research 97:6,959–6,982, https://doi.org/10.1029/91JB03065.

Carbotte, S.M., J.P. Canales, M.R. Nedimović, H. Carton, and J.C. Mutter. 2012. Recent seismic studies at the East Pacific Rise 8°20’–10°10’N and Endeavour Segment: Insights into mid-ocean ridge hydrothermal and magmatic processes. Oceanography 25(1):100–112, https://doi.org/10.5670/oceanog.2012.08.

Christie, D.M., and J.M. Sinton. 1981. Evolution of abyssal lavas along propagating segments of the Galapagos Spreading Center. Earth and Planetary Science Letters 56:321–335, https://doi.org/10.1016/0012-821X(81)90137-0.

Detrick, R.S., P. Buhl, E.E. Vera, J.C. Mutter, J.A. Orcutt, J.A. Madsen, and T.M. Brocher. 1987. Multi-channel seismic imaging of a crustal magma chamber along the East Pacific Rise. Nature 108:35–41, https://doi.org/10.1038/326035a0.

Escartín, J., S.A. Soule, D.J. Fornari, M.A. Tivey, H. Schouten, and M.R. Perfit. 2007. Interplay between faults and lava flows in construction of the upper oceanic crust: The East Pacific Rise crest 9°25’–58’N. Geochemistry Geophysics Geosystems 8, Q06005, https://doi.org/10.1029/2006GC001399.

Fornari, D.J. 2003. A new deep-sea towed digital camera and multi-rock coring system. Eos, Transactions, American Geophysical Union 84:69–76, https://doi.org/10.1029/2003EO080001.

Fornari, D.J., R.M. Haymon, M.R. Perfit, T.K.P. Gregg, and M.H. Edwards. 1998. Axial summit trough of the East Pacific Rise 9°–10°N: Geological characteristics and evolution of the axial zone on fast spreading mid-ocean ridges. Journal of Geophysical Research 103:9,827–9,855, https://doi.org/10.1029/98JB00028.

Fornari, D.J., M. Tivey, H. Schouten, M. Perfit, D. Yoerger, K.L. Von Damm, T. Shank, and A. Soule. 2004. Submarine lava flow emplacement at the East Pacific Rise 9°50’N: Implications from uppermost ocean crust stratigraphy and hydrothermal fluid circulation. Pp. 187–218 in Mid-Ocean Ridges: Hydrothermal Interactions Between the Lithosphere and Oceans. C.R. German, J. Lin, and L.M. Parson, eds, Geophysical Monograph Series, vol. 148, American Geophysical Union, Washington, DC.

Fornari, D.J., K.L. Von Damm, J.G. Bryce, J.P. Cowen, V. Ferrini, A. Fundis, M.D. Lilley, G.W. Luther III, L.S. Mullineaux, M.R. Perfit, and others. 2012. The East Pacific Rise between 9°N and 10°N: Twenty-five years of integrated, multidisciplinary oceanic spreading center studies. Oceanography 25(1):18–43, https://doi.org/10.5670/oceanog.2012.02.

Fundis, A., A.S. Soule, D.J. Fornari, and M.R. Perfit. 2010. Paving the seafloor: Volcanic emplacement processes during the 2005–06 eruption at the fast-spreading East Pacific Rise, 9°50’N. Geochemistry Geophysics Geosystems 11, Q08024, https://doi.org/10.1029/2010GC003058.

Goss, A., M.R. Perfit, W.I. Ridley, K.H. Rubin, G. Kamenov, A.S. Soule, A. Fundis, and D.J. Fornari. 2010. Geochemistry of lavas from the 2005–2006 eruption at the East Pacific Rise, 9°46’N–9°56’N: Implications for ridge crest plumbing and decadal changes in magma chamber compositions. Geochemistry Geophysics Geosystems 11, Q05T09, https://doi.org/10.1029/2009GC002977.

Klein, E.M. 2005. Geochemistry of the igneous oceanic crust. Pp. 433–464 in The Crust: Treatise on Geochemistry. R.L. Rudnick, ed., Elsevier–Pergamon, Oxford.

Kurras, G.J., D.J. Fornari, M.H. Edwards, M.R. Perfit, and M.C. Smith. 2000. Volcanic morphology of the East Pacific Rise crest 9°49’–52’: Implications for volcanic emplacement processes at fast-spreading mid-ocean ridges. Marine Geophysical Research 21(1-2):23–41, https://doi.org/10.1023/A:1004792202764.

Langmuir, C.H., J.F. Bender, and R. Batiza. 1986. Petrological and tectonic segmentation of the East Pacific Rise, 5°30’–14°30’N. Nature 322:422–429, https://doi.org/10.1038/322422a0.
le Roux, P.J., S.B. Shirey, E.H. Hauri, M.R. Perfit, and J.F. Bender. 2006. The effects of variable sources, processes and contaminants on the composition of northern EPR MORB 8–10°N and 12–14°N: Evidence from volatiles (H20, CO2, S) and Halogens (F, Cl). Earth and Planetary Science Letters 251:209–231, https://doi.org/10.1016/j.epsl.2006.09.012.

Perfit, M.R. 2001. Mid-ocean ridge geochemistry and petrology. Pp. 1,778–1,788 in Encyclopedia of Ocean Sciences. J. Steel, S. Thorpe, and K. Turekian, eds, Academic Press, San Diego, CA, https://doi.org/10.1006/rwos.2001.0096.

Perfit, M.R., and W.W. Chadwick Jr. 1998. Magmatism at mid-ocean ridges: Constraints from volcanological and geochemical investigations. Pp. 59–115 in Faulting and Magmatism at Mid-Ocean Ridges. W.R. Buck, T. Delaney, A. Karson, and Y. Lagabrielle, eds, Geophysical Monograph Series, vol. 106, American Geophysical Union, Washington, DC, https://doi.org/10.1029/GM106p0059.

Perfit, M.R., D.J. Fornari, M.C. Smith, J.F. Bender, C.H. Langmuir, and N.W. Hayman. 1994. Small-scale spatial and temporal variations in mid-ocean ridge crest magmatic processes. Geology 22:375–379, https://doi.org/10.1130/0091-7613(1994)022<0375:SSSATV>2.3.CO;2.

Ridley, W.I., M.R. Perfit, M.C. Smith, and D.J. Fornari. 2006. Magmatic processes in developing oceanic crust in a cumulate xenolith collected at the East Pacific Rise, 9°50’N. Geochemistry Geophysics Geosystems 7, Q12O04, https://doi.org/10.1029/2006GC001316.

Rubin, K.H., S.A. Soule, W.W. Chadwick Jr., D.J. Fornari, D.A. Clague, R.W. Embley, E.T. Baker, M.R. Perfit, D.W. Caress, and R.P. Dziak. 2012. Volcanic eruptions in the deep sea. Oceanography 25(1):142–157, https://doi.org/10.5670/oceanog.2012.12.

Rubin, K.H., and J.M. Sinton. 2007. Inferences on mid-ocean ridge thermal and magmatic structure from MORB compositions. Earth and Planetary Science Letters 260:257–276, https://doi.org/10.1016/j.epsl.2007.05.035.

Schouten, H., M. Tivey, D. Fornari, D. Yoerger, A. Bradley, P. Johnson, M. Edwards, and T. Kurokawa. 2002. Lava transport and accumulation processes on EPR 9°27’N to 10°N: Interpretations based on recent near-bottom sonar imaging and seafloor observations using ABE, Alvin and a new digital deep sea camera. Eos, Transactions, American Geophysical Union 83(19):Fall Meeting Supplement Abstract T11C-1262.

Sims, K.W.W., J. Blichert-Toft, D.J. Fornari, M.R. Perfit, S.J. Goldstein, P. Johnson, D.J. DePaolo, and P. Michael. 2003. Abberant youth: Chemical and isotopic constraints on the young off-axis lavas of the East Pacific Rise. Geochemistry Geophysics Geosystems 4, 8621, https://doi.org/10.1029/2002GC000443.

Sims, K.W.W., S.J. Goldstein, J. Blichert-Toft, M.R. Perfit, P.B. Kelemen, D.J. Fornari, P. Michael, M.T. Murrell, S.R. Hart, D.J. DePaolo, and others. 2002. Chemical and isotopic constraints on the generation and transport of magma beneath the East Pacific Rise. Geochimica et Cosmochimica Acta 66:3,481–3,504, https://doi.org/10.1016/S0016-7037(02)00909-2.

Sinton, J.M., S.M. Smaglik, J.J. Mahoney, and K.C. Macdonald. 1991. Magmatic processes at superfast spreading mid-ocean ridges: Glass compositional variations along the East Pacific Rise, 13°–23°S. Journal of Geophysical Research 96:6,133–6,155, https://doi.org/10.1029/90JB02454.

Smith, M.C., M.R. Perfit, D.J. Fornari, W.I. Ridley, M.H. Edwards, G.J. Kurras, and K.L. Von Damm. 2001. Magmatic processes and segmentation at a fast spreading mid-ocean ridge: Detailed investigation of an axial discontinuity on the East Pacific Rise crest at 9°37’N. Geochemistry Geophysics Geosystems 2, 1040, https://doi.org/10.1029/2000GC000134.

Soule, S.A., D.J. Fornari, M.R. Perfit, and K.H. Rubin. 2007. New insights into mid-ocean ridge volcanic processes from the 2005–2006 eruption of the East Pacific Rise, 9°46’N–9°56’N. Geology 35:1,079–1,082, https://doi.org/10.1130/G23924A.1.

Soule, S.A., J. Escartín, and D.J. Fornari. 2009. A record of eruption and intrusion at a fast spreading ridge axis: Axial summit trough of the East Pacific Rise at 9–10°N. Geochemistry Geophysics Geosystems 10, Q10T07, https://doi.org/10.1029/2008GC002354.

Soule, A.S., D.J. Fornari, M.R. Perfit, M.A. Tivey, W.I. Ridley, and H. Schouten. 2005. Channelized lava flows at the East Pacific Rise crest 9°–10°N: The importance of off-axis lava transport in developing the architecture of young oceanic crust. Geochemistry Geophysics Geosystems 6, Q08005, https://doi.org/10.1029/2005GC000912.

Wanless, V.D., M.R. Perfit, W.I. Ridley, and E.M. Klein. 2010. Dacite petrogenesis on mid-ocean ridges: Evidence for crustal melting and assimilation. Journal of Petrology 51:2,377–2,410, https://doi.org/10.1093/petrology/egq056.

Wanless, V.D., M.R. Perfit, W.I. Ridley, P. Wallace, C. Grimes, and E. Klein. 2011. Volatile abundances and oxygen isotopes in basaltic to dacitic lavas on mid-ocean ridges: The role of crustal assimilation at spreading centers. Chemical Geology 287:54–65, https://doi.org/10.1016/j.chemgeo.2011.05.017.

Waters, C.L., K.W.W. Sims, M.R. Perfit, J. Blichert-Toft, and J. Blusztajn. 2011. Perspective on the genesis of E-MORB from chemical and isotopic heterogeneity at 9–10°N East Pacific Rise. Journal of Petrology 52:565–602, https://doi.org/10.1093/petrology/egq091.

White, S.M., R.M. Haymon, D.J. Fornari, M.R. Perfit, and K.C. Macdonald. 2002. Correlation between tectonic and volcanic segmentation at fast-spreading ridges: Evidence from the distribution of volcanic structures and lava flow morphology along East Pacific Rise at 9°–10°N. Journal of Geophysical Research 107(B8), 2173, https://doi.org/10.1029/2001JB000571.

White, S.M., J.L. Mason, K.C. Macdonald, M.R. Perfit, V.D. Wanless, and E.M. Klein. 2009. Significance of widespread low effusion rate eruptions over the past two million years for delivery of magma to the overlapping spreading centers at 9°N East Pacific Rise. Earth and Planetary Science Letters 280:175–184, https://doi.org/10.1016/j.epsl.2009.01.030.

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