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The distribution of divalent trace elements between sulfides, oxides, silicates and hydrothermal solutions. I. Thermodynamic basis
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D. SubmarineGeologyand Geophysics Dept. of Earth Sci., Monash Univ., Clayton, Vic. 3168, Australia.
85:5094 Ferragne, A., C. Latouche and M. Parra, 1984. Lower Eocene red-clay sedimentation on the George Biigh/Rockall Channel. Geo-Marine Letts, 4(2):77-82. Inst. de Geol. du Bassin d'Aquitaine-351, Cours de la Liberation, 33405 Talence Cedex, France. 85:5095 Grousset, F. and O. Donard, 1984. Em'iclmaents in Hg, Cd, As, and Sb in recent sediments of Azores-Iceland Ridge. Geo-Marine Letts, 4(2): 117-124.
Evidence of submarine hydrothermal activity was found in the form of rift valley and transform fault (non-allochthonous) enrichments of Hg, Cd, As, and Sb in the 43°N to 47°N region of the Mid-Atlantic Ridge. A local hydrogenous flux is suggested as a possible source. Lab. Assoc. au CNRS, no. 197, Univ. Bordeaux I, 351 Crs. de la Liberation, 33405 Talence Cedex, France. (gsb) 85:5096 Hiscott, R.N., 1984. Clay mineralogy and claymineral provenance of Cretaceous and Paleogene strata, Labrador and Baffin shelves. Bull. can. Petrol. Geol., 32(3):272-280. Dept. of Earth Sci., Memorial Univ., St. John's, NF A1B 3X5, Canada. 85:5097 Stoffers, P., A. Sioulas, G.P. Glasby, W. Schmitz and A. Mangini, 1984. Sediments and mieronodules in the northern and central Peru Basin. Geologische Rdsch., 73(3): 1055-1080.
Because of the proximity of the basin to the CCD, surface sediments vary between calcareous oozes and siliceous muds. By far the most abundant clay mineral is smectite, thought to be of diagenetic origin. On a carbonate-free basis, the surface sediments are rather uniform in composition and similar to those of the equatorial Pacific. Sedimentation rates range 3 to 5 ram/1000 yr. Micronodule compositions show significant variations related to the size class of the micronodules and the depth of occurrence within the sediment column. The dominant mineral phase is todorokite. Inst. fur Sediment., Univ. Heidelberg, P.O. 103 020, D-6900 Heidelberg, FRG.
OLR(1985)32 (9)
DI40. Submarine hydrology (springs, hydrothermal deposits, etc.) 85:5098 Lafitte, Michel, 1984. A comparative mineralogical study of sulfides from E.P.R. 21 ° North, 13 ° North and from Cyprus deposits [supports a common mechanism of formation for these sulfldesl. C. r. Acad. Sci., Paris, (S6r. 11)299(20): 1397-1400. (In French, English abstract.) Lab. de Min. exper, et appl., Univ. P. et M.C., Tour 25, 4, place Jussieu, 75230 Paris Cedex 05, France. 85:5099 Sverjensky, D.A., 1985. The distribution of divalent trace elements between sulfides, oxides, silicates and hydrotbermal solutions. I. Thermodynamic basis. Geochim. cosmochim. Acta, 49(3):853-864. Dept. of Earth and Planet. Sci., Johns Hopkins Univ., Baltimore, MD 21218, USA.
DI70. Historical geology, stratigraphy 85:5100 Berger, W.H., J.S. Kitlingley, C.V. Metzler and E. Vincent, 1985. Two-step deglaciation: ~4C--dated high-resolution 8~sO records from the tropical Atlantic Ocean. Quat. Res., 23(2):258-271.
Globorotalia menardii abundances, 31 radiocarbon dates, and 150 oxygen isotope determinations were obtained for 8 box cores from the tropical Atlantic to construct a detailed 8~so record. The results indicate that the change from glacial to postglacial conditions was not abrupt. The onset of deglaciation is dated about 15,000 yrBP. A pause between 11,000 and 12,000 yrBP may be correlative with the Younger Dryas at 10,500 yrBP. A brief excursion of light oxygen values, following a second deglaciation phase centered around 10,000 yrBP may be the equivalent of the Gulf of Mexico meltwater spike. Scripps Inst. of Oceanogr., La Jolla, CA 92093, USA.
(hbf) 85:5101 Berger, W.H., J.S. Killingley and E. Vincent, 1985. Timing of deglaciation from an oxygen isotope curve for Atlantic deep-sea sedln~nts. Nature, Lond., 314(6007): 156-158.
Evidence is produced from box cores taken in the equatorial Atlantic that the last deglaciation occurred in two major steps separated by a brief pause. It is proposed that this pause is equivalent to the period of glacial readvance known as 'Younger
D. SubmarineGeologyand Geophysics Dept. of Earth Sci., Monash Univ., Clayton, Vic. 3168, Australia.
85:5094 Ferragne, A., C. Latouche and M. Parra, 1984. Lower Eocene red-clay sedimentation on the George Biigh/Rockall Channel. Geo-Marine Letts, 4(2):77-82. Inst. de Geol. du Bassin d'Aquitaine-351, Cours de la Liberation, 33405 Talence Cedex, France. 85:5095 Grousset, F. and O. Donard, 1984. Em'iclmaents in Hg, Cd, As, and Sb in recent sediments of Azores-Iceland Ridge. Geo-Marine Letts, 4(2): 117-124.
Evidence of submarine hydrothermal activity was found in the form of rift valley and transform fault (non-allochthonous) enrichments of Hg, Cd, As, and Sb in the 43°N to 47°N region of the Mid-Atlantic Ridge. A local hydrogenous flux is suggested as a possible source. Lab. Assoc. au CNRS, no. 197, Univ. Bordeaux I, 351 Crs. de la Liberation, 33405 Talence Cedex, France. (gsb) 85:5096 Hiscott, R.N., 1984. Clay mineralogy and claymineral provenance of Cretaceous and Paleogene strata, Labrador and Baffin shelves. Bull. can. Petrol. Geol., 32(3):272-280. Dept. of Earth Sci., Memorial Univ., St. John's, NF A1B 3X5, Canada. 85:5097 Stoffers, P., A. Sioulas, G.P. Glasby, W. Schmitz and A. Mangini, 1984. Sediments and mieronodules in the northern and central Peru Basin. Geologische Rdsch., 73(3): 1055-1080.
Because of the proximity of the basin to the CCD, surface sediments vary between calcareous oozes and siliceous muds. By far the most abundant clay mineral is smectite, thought to be of diagenetic origin. On a carbonate-free basis, the surface sediments are rather uniform in composition and similar to those of the equatorial Pacific. Sedimentation rates range 3 to 5 ram/1000 yr. Micronodule compositions show significant variations related to the size class of the micronodules and the depth of occurrence within the sediment column. The dominant mineral phase is todorokite. Inst. fur Sediment., Univ. Heidelberg, P.O. 103 020, D-6900 Heidelberg, FRG.
OLR(1985)32 (9)
DI40. Submarine hydrology (springs, hydrothermal deposits, etc.) 85:5098 Lafitte, Michel, 1984. A comparative mineralogical study of sulfides from E.P.R. 21 ° North, 13 ° North and from Cyprus deposits [supports a common mechanism of formation for these sulfldesl. C. r. Acad. Sci., Paris, (S6r. 11)299(20): 1397-1400. (In French, English abstract.) Lab. de Min. exper, et appl., Univ. P. et M.C., Tour 25, 4, place Jussieu, 75230 Paris Cedex 05, France. 85:5099 Sverjensky, D.A., 1985. The distribution of divalent trace elements between sulfides, oxides, silicates and hydrotbermal solutions. I. Thermodynamic basis. Geochim. cosmochim. Acta, 49(3):853-864. Dept. of Earth and Planet. Sci., Johns Hopkins Univ., Baltimore, MD 21218, USA.
DI70. Historical geology, stratigraphy 85:5100 Berger, W.H., J.S. Kitlingley, C.V. Metzler and E. Vincent, 1985. Two-step deglaciation: ~4C--dated high-resolution 8~sO records from the tropical Atlantic Ocean. Quat. Res., 23(2):258-271.
Globorotalia menardii abundances, 31 radiocarbon dates, and 150 oxygen isotope determinations were obtained for 8 box cores from the tropical Atlantic to construct a detailed 8~so record. The results indicate that the change from glacial to postglacial conditions was not abrupt. The onset of deglaciation is dated about 15,000 yrBP. A pause between 11,000 and 12,000 yrBP may be correlative with the Younger Dryas at 10,500 yrBP. A brief excursion of light oxygen values, following a second deglaciation phase centered around 10,000 yrBP may be the equivalent of the Gulf of Mexico meltwater spike. Scripps Inst. of Oceanogr., La Jolla, CA 92093, USA.
(hbf) 85:5101 Berger, W.H., J.S. Killingley and E. Vincent, 1985. Timing of deglaciation from an oxygen isotope curve for Atlantic deep-sea sedln~nts. Nature, Lond., 314(6007): 156-158.
Evidence is produced from box cores taken in the equatorial Atlantic that the last deglaciation occurred in two major steps separated by a brief pause. It is proposed that this pause is equivalent to the period of glacial readvance known as 'Younger