Serpentine seamounts

Benton LD, Tera F (2000) Lithium isotope systematics of the Marianas revisited. J Conf Abst 5 210 Benton LD, Savov 1, Ryan JG (1999) Recycling of subducted lithium in forearcs Insights from a serpentine seamount. EOS Trans, Am Geophys Union 80 S349... 

Benton L. D., Ryan J. G., and Tera F. (2001) Boron isotope systematics of slab fluids as inferred from a serpentine seamount, Mariana forearc. Earth Planet. Sci. Lett. 187, 273-282. 

Haggerty J. A. (1991) Evidence from fluid seeps atop serpentine seamounts in the Mariana forearc clues for emplacement of the seamounts and their relationship to forearc tectonics. Mar. Geol. 102, 293-309. 

Mottl M. J. (1992) Pore waters from serpentine seamounts in the Mariana and Izu-Bonin Eorearcs, Leg 125 evidence for volatiles from the subducting slab. Proc. ODP Sci. Results 125, 373-385. 

Figure 3 Plots of element abundances versus depth below seafloor (meters) for serpentinized ultramafic clasts from hole 779A in Conical Seamount, Mariana fore-arc, collected during ODP leg 125 (Ryan et al. (1996a)). Shaded fields represent the range of enriched and depleted mantle compositions (source McDonough and Sun, 1995).

Fryer P. and Mottl M. (1992) Lithology, mineralogy, and origin of serpentine muds recovered from Conical and Torishima forearc seamounts results from Leg 125 drilling. Proc. OOP Sci. Results 125, 343-362. 

The seamounts are built on fore-arc crust 20-35 km above the downgoing Pacific plate, and are essentially mud volcanoes erupting finegrained serpentine with entrained, highly serpenti-nized blocks of harzburgite and dunite, and... 

The objective of this chapter is to review available stable isotopic data on seafloor hydrothermal systems. However, this goes far beyond a simple literature review because much new, previously unpublished data, collected by the author, is included. In addition, an important goal of this chapter is to interpret the stable isotope systematics of seafloor hydrothermal systems in the context of fluid-rock reactions and geochemical reaction calculations. Boiling and supercritical phase-separation, volcanic eruption and dike-emplacement events, addition of magmatic volatiles, and bacterial fractionation processes will be discussed where applicable. In addition to the commonly measured stable isotopes of C, O, H, and S, stable isotope ratios of B, Li, N, Cl, Cu, and Fe are included where data are available. Much new data has appeared since the last comprehensive overview of stable isotopes in seafloor hydrothermal systems (Shanks et al. 1995). This includes a wealth of information on hydrothermal systems related to volcanic arcs, back-arc spreading centers, seamounts, and serpentinized ultramafics. 

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