Galapagos rift

Bischoff, J.L., Rosenbauer, R.J., Aruscavage, P.J., Baedecker, A.L. and Crock, J.G. (1983) Seafloor massive sulfide deposits from 2I°N, East Pacific Rise Juan de Fuca Ridge and Galapagos rift Bulk chemical composition and economic implications. Econ. Geo ., 78, I711-1720. 

Figure 4.6 Large excesses of juvenile He in hydrothermal waters sampled at specific vent fields in the Galapagos Rift. Note ambient sea water concentration near origin (cf. Table 4.6). Reproduced from Jenkins et al. (1978).

More detailed examination and sampling allows association of hydrothermal circulation with specific vent fields. In such waters samples in the Galapagos Rift by the Alvin deep submersible, Jenkins, Edmond, and Corliss (1978) report juvenile He enrichments which dwarf the normal saturation concentrations by factors up to 11 for 4He and 60 for 3He (Figure 4.6). A particularly significant feature of this report is that added He occurs roughly in proportion to added heat AT up to 12°C in sampled water), corresponding to about 7.6 x 10 xcal/atom of 3He (Figure 4.7). Jenkins et al. note that if this value is representative, hydrothermal circulation may indeed account for the depression of conductive heat flow relative to models for total heat flux. As... 

Lupton, J. E., Weiss, R. F., Craig, H. (1977b). Mantle helium in hydrothermal plumes in the Galapagos Rift. Nature, 267, 603 1. 

Corliss J. B., Lyle M., and Dymond J. (1978) The chemistry of hydrothermal mounds near the Galapagos rift. Earth Planet Sci. Lett 40, 12-24. 

Haymon R. M. (1989) Hydrothermal processes and products on the Galapagos Rift and East Pacific Rise, chap. 8. In The Eastern Pacific Ocean and Hawaii, The Geology of North America (eds. E. L. Winterer, D. M. Hussong, and R. W. Decker). Geol. Soc. Am., Boulder, CO, vol. N, pp. 125-144. 

SEPR 2rN EPR 13 N EPR 11 N EPR 9-10"N EPR ODR 504B Galapagos Rift Axial Seamount SJFR... 

Explorer Ridge, Endeavour Ridge, Axial Seamount, Cleft Segm ent. East Pacific Rise, Galapagos Rift, TAG, Snake Pit, Mid-Atlantic Ridge 24.5°N... 

Perfit, M.R., Fornari, D.J., Malahoff, A. and Embley, R.W., 1983. Geochemical studies of abyssal lavas recovered by DSRV Alvin from eastern Galapagos Rift, Inca Transform, and Equador Rift, 3. Trace Element abundances and pertogenesis. Journal of Geophysical Research, 88 10551-10572. 

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