ISSN 0002-3272 Vol. 581:Alteration effects in the upper oceanic crust – data and comments (Technical Note) /
V.B. Kurnosov, B.P. Zolotarev, A.V. Artamonov,S.M. Lyapunov, G.L. Kashinzev, O.V. Chudaev, A.L. Sokolova, and S.A. Garanina – Moscow: GEOS, 2008. – 32 p. (Booklet) + full version (see CD-ROM volume or WWW PDF volume) – 1046 p.; il. 139.
This report presents new data on chemical and mineralogical composition and density of altered and fresh igneous rocks from key Deep Sea Drilling Project (DSDP)/Ocean Drilling Program (ODP) holes drilled on the following main tectonomagmatic structures of the ocean floor: mid-ocean ridges and abyssal plains and basins (DSDP Legs 37, 61, 63, 64, 65, 69, 70, 83, and 91 and ODP Legs 106, 111, 123, 129, 137, 139, 140, 148, and 169); seamounts and guyots (DSDP Legs 19, 55, and 62 and ODP Legs 143 and 144); intraplate rises (DSDP Legs 26, 33, 51, 52, 53, 72, and 74 and ODP Legs 104, 115, 120, 121, and 183); and marginal seas (DSDP Legs 19, 59, and 60 and ODP Legs 124, 125, 126, 127, 128, and 135). Study results of altered gabbro from the Southwest Indian Ridge (ODP Leg 118) and serpentinized ultramafic rocks from the Galicia margin (ODP Leg 103) are also presented. Samples were collected by the authors from the DSDP/ODPrepositories, as well as during some Glomar Challengerand JOIDES Resolutionlegs. This report also includes descriptions of thin sections, geochemical diagrams, data on secondary mineral assemblages, and recalculated results of chemical analyses with corrections for rock density. The atomic content of each element can be quantified in grams per standard volume (g/1000 cm3). The suite of results can be used to estimate mass balance, but parts of the data need additional work, which depends on locating fresh analogs of the altered rocks studied here. Results of quantitative estimation of element mobility in recovered sections of the upper oceanic crust as a whole are shown for certain cases: Hole 504B (Costa Rica Rift) and Holes 856H, 857C, and857D (Middle Valley, Juan de Fuca Ridge).