Seafloor basalts

Ludden, J. and Thompson, G. (1979) An evaluation of the behavior of rare earth elements during the weathering of seafloor basalts. Earth Planet. Sci. Lett., 43, 85-92. 

Biogeochemistry of off-axis vents and seafloor basalt 8.2.5.1 Off-axis vents... 

Mid-ocean ridge hydrothermal processes provide an ideal application for geochemical reaction path modeling, involving temperature dependent reactions, fluid mixing, reaction with sulfide products, and reaction with seafloor basalts (5). The solution and solid compositions are well characterized, including that of sulfur isotopes (10.11). However, measured fractionations between solution and solid samples can not be the result of simple equilibrium processes f 10-121. The ability to track reactions involving seawater sulfate = 21 per mil) and hydrother-... 

Bischoff, J.L. and Dickson, F.W. (1975) Seawater-basalt interaction at 200°C and 500 bars Implications for origin of seafloor heavy-metal deposits and regulation of seawater chemistry. Earth Planet. Sci. Lett., 25, 385-397. 

Average bulk compositions of samples from seafloor sulfide deposits at sediment-starved midocean ridges in host basalts... 

Mariko, T. (1984) Sub-seafloor hydrothermal alteration of basalt, diabase and the Shimokawa copper mining area, Hokkaido, Japan. Mining Geology, 34, 307-322. 

Staudigel H, Plank T, White B, Schmincke H-U (1996) Geochemical fluxes during seafloor alteration of the basaltic upper oceanic crust DSDP Sites 417 and 418. In Subduction Top to Bottom. Bebout GE, Scholl DW, Kirby SH, Platt JP(eds), AGU, Washington DC, p 19-37 Suman DO, Bacon MP (1989) Variations in Holocene sedimentation in the North American Basin determined by °Th measurements. Deep Sea Res 36 869-787... 

Chlorine isotope compositions vary by up to 15%o (Chapter 7 Stewart and Spivack 2004). These large variations in Cl isotope compositions are found in marine environments, including mid-ocean ridge basalts, seafloor and hydrothermal alteration products, and sedimentary pore... 

Pillow basalts Large mounds of basalt that form when lava is extruded onto the seafloor at active spreading centers. 

Thompson G. (1983a) Basalt-seawater interaction. In Hydrothermal Processes at Seafloor Spreading Centers (eds. P.A. Rona, K. Bostrom, L. Laubjer and K.L. Smith), pp. 225-278. Plenum Press, New York. 

The situation in any single plume appears to be complex the Hawaii case is illustrative. Dixon et al. (1997) estimated H2O concentrations of 525 75 ppm in the source for North Arch basalts, a seafloor field of alkalic basalts north of Oahu. Wallace (1998) estimated 450 190 ppm H2O in the source for Kilauea basalts, and Dixon and Clague (2001) inferred 400 30 ppm H2O in the source for Loihi seamount basalts. Dixon and Clague (2001) argue that these differences are consistent with a mantle plume with multiple components, such as a wet rim and dry core plume model as proposed by Sen et al. (1996). 

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