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Geochemistry, Geophysics, Geosystems
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Supporting Information for
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Phosphorites, Co-rich Mn nodules, and Fe-Mn crusts from Galicia Bank, NE
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Atlantic: Reflections of Cenozoic tectonics and paleoceanography
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Geological Survey of Spain (IGME), C/ Ríos Rosas 23, 28003 Madrid, Spain
U. S. Geological Survey (USGS), Pacific Coastal and Marine Science Center, Santa
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Cruz, CA, United States
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Estación de Bioloxía Mariña da Graña, Universidade de Santiago de Compostela, Rúa
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da Ribeira 1–4 (A Graña), 15590 Ferrol, Spain
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*Corresponding Author: F.J. González, Geological Survey of Spain (IGME), C/Ríos
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Rosas 23, 28003 Madrid, Spain. (fj.gonzalez@igme.es)
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Contents of this file
Text S1 to S5
Figures S1 to S3
Tables S1 to S3
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Introduction
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This supporting information provides a general description of samples recovered and Lab
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methods (geophysics, mineralogy and geochemistry); supplementary information of
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geological setting and additional figures of seismic profiles in the studied area; XRD
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mineralogical data and diffractograms and EPMA geochemical analysis of mineral phases
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in phosphorites and ferromanganese deposits.
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Text S1.
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1. Data and methods
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1.1. Bathymetry and seismic reflection data
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36
MHRS profiles were collected using an array of five GI-guns© (two of 45 ci,
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two of 13 ci, and one of 24 ci) with a total volume of 140 ci. The GI-guns© were
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fired at a shot-spacing of 25 m, corresponding approximately every 10 s and
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recording 8 s. Data were received using a high-resolution seismic data acquisition
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system. The total active streamer was 600 m, consisting of 72 channels. The
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average penetration reached by the acoustic signal was about 2.5 s two-way travel
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time (TWTT). The MBES data were collected with the hull-mounted Simrad EM-
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12 dual echosounder system, which collected bathymetric and backscatter data.
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The MBES operated at a frequency of 12/13 kHz at a ping rate of 10 s. It has a fan
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width of 150º consisting of 162 beams of 1.8°/3.5° each. Our bathymetric data were
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combined with those obtained for the mapping of the Exclusive Economic Zone
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(ZEEE) of Spain in the area of the Galicia margin, collected from 2001 to 2005.
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In order to constrain the age of episodes of mineralization that occurred in
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the region of Galicia Bank, we carried out a seismo-stratigraphic analysis of high-
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resolution multichannel seismic data to identify major regional discontinuities.
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This task ties in to previous studies on Mesozoic-Cenozoic stratigraphy, magnetic
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anomalies, and seismo-stratigraphic architecture determined for Galicia Bank and
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along the adjacent continental margins of the northern Iberian Peninsula (Groupe
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Galicia, 1979; Mauffret and Montadert, 1988; Murillas et al., 1990; Cande and
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Kent, 1992; Sibuet, 1992; Thinon, 1999; Vázquez et al., 2008; Ercilla et al., 2011).
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57
1.2. Sample analyses techniques
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Dredge (2 m by 0.8 m) hauls recovered slabs of white phosphorite
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impregnated with black Fe-Mn oxides, black Mn nodules, Fe-rich reddish nodules,
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and several fragments of igneous, metamorphic, and sedimentary rocks from
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basement outcrops and ice-rafted drop stones. In addition, a large collection of
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living and dead cold-water Scleractinia corals (Lophelia Pertusa, Madrepora
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Occulata) and other encrusting organisms was recovered (Somoza et al., 2014).
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Large slabs of phosphorite (<1m in maximum dimension) were collected at four
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stations: DRR36, DRR38, DRR47 and DRR81 (Fig. 2). Individual samples range
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from a few grams for nodules to ≈100 kg for large pavement-like slabs. Fe-Mn
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nodules and crusts were collected at nine stations: DRR-20, DRR21, DRR25,
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DRR36, DRR37, DRR38, DRR41, DRR47, DRR81 and DRR91 (Fig. 2). Thin Fe-
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Mn crusts coat all the hard substrates present in the area (basement rocks, drop
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stones, phosphorite slabs and nodules, and Fe-Mn deposits). Fe-Mn patinas,
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impregnations, and breccias of variable centimetre thicknesses occur on the
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surface and underside surface of many phosphorite slabs from stations DRR47 and
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DRR81 (Fig. 2). Previously MBES backscatter data and MHRS profiles indicated
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the presence of these deposits.
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Analyses were carried out in the Central Labs of the Geological Survey of
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Spain (IGME), the Pacific Coastal and Marine Science Center of the United States
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Geological Survey (USGS), the “CAI de Geocronología y Geoquímica Isotópica”,
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and the “Centro Nacional de Microscopía Electrónica” at the Complutense
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University of Madrid (UCM).
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Thin and polished sections of phosphorite and Fe-Mn nodules and crusts
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were prepared and studied under the petrographic and electron (SEM-EPMA)
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microscopes. Bulk mineralogical X-ray powder diffraction (XRD) profiles from 2θ
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2–60° in 0.005 steps were obtained for 21 sub-samples using XPERT PRO of
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PANalytical, Cu-Kα radiation (40 kV and 40 mA) with graphite monochromator,
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High Score software and ICDD data base. Samples for EPMA analysis were
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selected based on the microscopic observations to represent all the mineral deposit
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types. Analyses were conducted using a JEOL Superprobe JXA-8900 M, operating
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at 15–20 kV and 50 mA, fitted with wavelength dispersive spectrometers (WDS).
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Back-scattered electron images were also obtained with this instrument. Profiles
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across nodular samples were obtained to check the presence of compositional
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zoning. Standards included pure metals, synthetic and natural minerals, all from
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international suppliers. Sub-millimetre ferromanganese laminae of vernadite that
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encrusts phosphorite slabs and nodules were analysed using EPMA for samples
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DRR38-2 and DRR81-5. In addition, the external margin (vernadite patina) of Co-
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rich manganese nodule DRR81-1 and Fe-rich nodule DRR38-8 were studied by
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EPMA.
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The Fe-Mn crusts and phosphorite slabs were separated into distinct layers
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and textural types (massive, laminated and brecciated) for chemical and
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mineralogical analyses. Major and trace elements contents of bulk samples were
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analysed by X-ray fluorescence (XRF) using a MagiX of PANalytical instrument
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with Rh radiation, and by induction coupled plasma atomic emission spectrometry
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(ICP-AES) respectively. Au and Na were measured using a VARIAN FS-220
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atomic absorption spectrometre. Accuracy of the data was checked by using
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international standard reference materials, and precision based on duplicate
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samples was found to be better than ±5%.
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Loss on ignition (LOI) was determined by calcination at 950 °C and S was
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measured using ELTRA CS-800 equipment. REY concentrations of selected
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samples were determined by ICP mass spectrometry (ICP-MS) using an Agilent
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7500 ce instrument. The standard reference materials SO-1 (CCMET), GSP-1
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(USGS) and BCR-1 (USGS) were used to test the analytical procedure for REY
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determinations. The accuracy and precision obtained were better than 10% for all
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REY. REY were normalised to shale (Post-Archean Australian Shale, PAAS;
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McLennan, 1989) for plotting. The Ce anomaly (Ce*) was calculated as Ce* = Log
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(Ce/(2/3La+1/3Nd)), all values normalised to PAAS. The Pearson product moment
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correlation coefficient was used to produce correlation matrices.
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Sr isotopic analyses are used to constraint the timing of phosphogenesis and
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the history of mineralization fluids in the Galicia Bank region. Nd isotopes were
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also measured to determine the source of the mineralization fluids. The isotopic
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analyses were based on bulk mineralized samples, micro-drilling of selected parts,
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and leaching experiments (Table 3). All samples were dried to constant weight and
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ground to 160 mesh. The bulk samples were digested in HCl–HNO3–HF mixture to
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allow analysis of the bulk sample. Details of protocols of sample preparation are
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given in Galindo et al. (1994) and Darbyshire and Shepherd (1994). The leaching
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procedure uses 5 ml of 2.5N HCl for 20 min to obtain the carbonate fraction. After
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leaching, the dissolutions were centrifuged at 4000 rpm for 10 min, and then the
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supernatant was decanted and evaporated.
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For Sr isotope ratio analyses, Sr was separated from the samples using
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standard ion exchange techniques detailed in Galindo et al. (1994). Sr isotope ratio
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measurements were made on a automate collector Phoenix TIMS mass
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spectrometer with 9 collectors at the Center of Geochronology and Isotopic
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Geochemistry of the Complutense University of Madrid. Reproducibility and
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accuracy of Sr isotope runs were checked periodically by running the Standard
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Reference Material NBS 987 along with the samples, with a mean 87Sr/86Sr value of
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0.710240 ±0.00001 (2σ external standard deviation, n=14). The Sr isotopic ratios
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were normalized to 86Sr/88Sr=0.1194.
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Reproducibility and accuracy of Nd isotope runs were checked periodically
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by running the Standard Reference Material LaJolla along with the samples, with
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a mean
140
n=27).
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Reproducibility of Sr and Nd isotopic measurements was determined by repeat
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analysis of samples and standards, which show analytical errors of 0.01% for
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87Sr/86Sr
144
((143Nd/144Nd)sample/(143Nd/144Nd)CHUR - 1) * 10,000, where CHUR (Chondritic
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Uniform Reservoir) is equivalent to the bulk Earth
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(DePaolo and Wasserburg, 1976). ƐNd(t) was calculated using
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0.115.
143Nd/144Nd
value of 0.511848 ± 0.000003 (2σ external standard deviation,
The Nd isotopic ratios were normalized to
and 0.006% for
148
149
Text S2.
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2. Geological setting
143Nd/144Nd
146Nd/144Nd=0.7219.
of the standard deviation. Nd(0) =
143Nd/144Nd
ratio or ~0.512638
147Sm/144Nd/
CHUR(0)
=
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Galicia Bank is bordered by two different margins (e.g. Boilllot et al., 1989):
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(1) to the west, a passive rifted margin that resulted from the extension and
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breakup between America and Iberia during the Early Cretaceous. Samples
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recovered from the basement of the Galicia margin, especially at the fault scarps
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where basement crops out, reveal the nature of that margin. Metamorphic and
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plutonic rocks belong to two Variscan zones defined for on-land deposits
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(Capdevila and Mougenot, 1988). Tonalites and granodiorites, commonly found in
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the Ossa Morena zone, have been collected from Galicia Bank, Vasco de Gama and
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Vigo seamounts. Amphibolite, eclogite, gneiss, high-pressure granulite, and granite
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sampled along the northern Galicia margin belong to the Central Iberian Zone; (2)
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north of Galicia Bank occurs a Paleogene active margin. There, short-duration,
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latest Mesozoic-Early Cenozoic convergence between the Iberian and European
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plates transformed a Cretaceous passive margin into an active margin related to
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the southward subduction of the ocean lithosphere (Boillot and Mallod, 1988). The
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accretionary prism produced by this subduction appears to have been actively
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forming at least during Lutetian (middle Eocene) to Burdigalian (early Miocene)
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times (Alvarez-Marrón et al. 1997). Thus, the northwestern slope of Galicia Bank
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is composed of outcrops of mafic igneous rocks (basalts and gabbros) and
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peridotites (lherzolites, metasomatized peridotites, harzburgites) (Boillot et al.,
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1980; Cornen et al., 1999; Chazot et al., 2005). This zone has been interpreted as
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the margin of oceanic lithosphere accreted to the Iberian plate as a result of
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Cenozoic subduction. (Malod et al., 1993) and exhumed sub-continental
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lithospheric mantle respectively (e.g. Boillot et al., 1988). Syn- and post-rift
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hydrothermal activity at shallow levels of the lithosphere has been proposed to
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explain the serpentinization of peridotite (e.g. Boillot et al., 1989).
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177
178
179
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Figure S1. NW-SE A04 multichannel seismic profile across the base and the Sancho
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Seamount. Vertical exaggeration is x8 (V= 2.0Km/s). Upper left is the location of seismic
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profile and dredge station. A large suite of phosphorite slabs were collected from the top
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of the seamount linked to the D1 discontinuity. Below on the right, phosphorite slab
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showing a set of parallel fractures and partially replaced by Mn oxides (black) around the
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margins and along fractures; pale-brown carbonate sediments fill cavities that were first
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lined by Mn oxide.
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188
189
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191
192
193
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Figure S2. W-E A24 multichannel seismic profile across southern Galicia Bank (see Fig.
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2). Vertical exaggeration is x32 (V= 2.0Km/s). Mineral deposition can be associated with
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the seismic stratigraphy: Type 1, phosphorite hardground marks the D1 discontinuity;
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Type 2, hydrogenetic Fe-Mn crusts are associated with the U2 contourite unit; Type 3, Co-
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rich Mn nodules and Fe-Mn replaced phosphorite are linked to acoustic blanking related
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to upflow zones of fluids and sediment; Type 4, Fe-rich nodules are associated with
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contourites formed by the MOW.
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Text S3.
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3. Mineralogy
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The XRD patterns of bulk samples and EPMA analyses show fluorapatite
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as the primary mineral and carbonate CFA as accessory (Figs.S3A and B).
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Fluorapatite has three main X-ray reflections at 2.79 Å, 2.69 Å and 2.77 Å. The
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crystallite size must be large as indicated by the sharp X-ray reflections on the
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XRD patterns. We cannot distinguish crystal morphologies, but the XRD patterns
209
show resolved peaks reflecting moderate to high crystallinity of the phosphate
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mineral phases. Pyrite was not detected in the phosphate slabs or nodules.
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With respect to ferromanganese oxides, vernadite has two X-ray reflections at 2.45
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Å and 1.41 Å in Fe-Mn crusts. Asbolane has X-ray reflections at 4.81Å, 2.45 Å, 9.6
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Å, 1.71 Å and 1.41 Å (Fig. S3D). The XRD patterns of bulk Co-rich nodules show
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10 Å manganates as predominant: romanechite as the primary Mn mineral and
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coronadite and todorokite as accessories (Figs. S3C and E ). Goethite has two X-
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ray reflections at 2.47 Å and 4.20 Å being the principal mineral in Fe-rich nodules
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followed by lepidocrocite (Fig. S3F).
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219
Figure S3. XRD profiles for (A) phosphorite; (B) brecciated and Fe-Mn replaced
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phosphorite that replaced limestone; (C, E) Co-rich Mn nodule; (D) hydrogenetic Fe-Mn
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crust; (F) Fe-rich nodule. ca=calcite, CFA=carbonate fluorapatite, to=todorokite,
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bi=birnesite,
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goe=goethite, lep=lepidocrocite.
rom=romanechite,
ver=vernadite,
asb=asbolane,
cor=coronadite,
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225
Text S4.
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4. Electron Micro Probe Analysis and Pearson correlation Index
227
228
For six samples of phosphorites, P has a positive correlation with F (0.82)
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and Na (0.8) (Table S1). The terrigenous elements Si, Al, Mg, K and Ti show
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positive correlations among members of that group (0.8-0.9). Fe exhibits a positive
231
correlation with Mn (0.86) and a negative correlation with Ca (-0.93). Ca shows a
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negative correlation with Mn (-0.96) and Mg (-0.86).
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Microprobe analyses of phosphate minerals in slabs and nodules show that
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CFA in slabs significantly concentrates F (up to 4.1 wt%), CaO (48.2 to 53.2 wt%),
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P2O5 (29.8 to 34.3 wt%), and SO3 (up to 1.4 wt%; Table S2). Phosphorite slabs
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showing replacement by Fe-Mn oxyhydroxides have characteristic geochemical
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zonations: Fe and Mn are strongly enriched in the replaced margins compared to
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the unaltered phosphorite slabs (up to 49.7 wt% MnO and 7.8 wt% FeO); Sr, Ba,
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Ni, Co and Pb are also enriched along with the Mn and Fe, but P2O5 contents are
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lower (Table S2, analyses DRR47-2-(3, 4, 12)). Phosphate nodules have P2O5
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contents that are slightly lower than the phosphorite slabs (from 27.2 to 30.3 wt%),
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and the nodules show higher contents in FeO (up to 5.3 wt%) and MnO (up to 5.8
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wt%).
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Elements in the Fe-Mn deposits are associated with different mineral
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phases: vernadite, goethite, 7 Å and 10 Å manganates, aluminosilicates, biogenic
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carbonate clasts or carbonates filling porosity, Mn-carbonates, and CFA.
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Microprobe point analyses of vernadite, which encrusts the surface of Fe-Mn
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nodules and phosphates, show variable contents of major, minor and trace metals
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among different samples but also among laminations in the same sample (Table
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S3). For vernadite, Mn/Fe ratios are close to 1 with high Co contents (up to 1.3
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wt%) and Pb (up to 0.67 wt%) and minor Ni. In other samples, Mn/Fe ratios are
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higher (up to 500) accompanied by Ni contents (up to 3 wt%) and Cu contents (up
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to 0.3 wt%). The 7 Å and 10 Å manganates in the Co-rich Mn nodules, such as
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DRR81-1, concentrate Mn (up to 60.7 wt% MnO), with high contents in Mg, Ca,
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Na, and K, and also elements of potential economic interest: Co (up to 5.6 wt%),
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Ba (up to 6.6 wt%), Ni (up to 1.2 wt%), and Cu (up to 0.2 wt%). Mn-carbonate
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laminae in these nodules concentrate Ca, Mn, Mg, Co and P. The goethite in Fe-
258
rich nodules concentrates only Fe (up to 75 wt% FeO), with low concentrations of
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other metals. Detrital phyllosilicates host Al, Si and K and frequently also Fe and
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Mg, whereas bioclasts in phosphorite and Fe-Mn nodule content show high Ca, Mg
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and Sr.
262
263
Text S5.
264
5. References
265
Boillot, G., Grimaud, S., Mauffret, A., Mougenot, D., Kornprobst, J., Mergoil-
266
Daniel, J., and G. Torrent (1980), Ocean-Continent Boundary Off the Iberian
267
Margin: a Serpentinite Diapir West of the Galicia Bank. Earth Planet. Sci. Lett.,
268
48(1), 23-34.
269
Boillot, G., Mougenot, D., Girardeau, J., and E. L. Winterer (1989), Rifting
270
Processes on the West Galicia Margin, Spain. In: A.J. Tankard and H.R. Balkwill
271
(Eds.) Extensional Tectonics and Stratigraphy of the North Atlantic Margins.
272
AAPG Memoir 46, 363-377.
273
Chazot, G., Charpentier, S., Kornprobst, J., Vannucci, R., and B. Luais (2005),
274
Lithospheric Mantle Evolution during continental Break-Up: The Wes Iberia Non-
275
Volcanic Passive Margin. J. Petrol., 46 (12), 2527-2568.
276
Cornen, G., Girardeau, J., and C. Monnier (1999), Basalts, underplated gabbros
277
and pyroxenites record the rifting process of the West Iberian margin. Min. and
278
Petrol., 67, 111-142
279
Darbyshire, D. P. F., and T. J. Shepherd (1985), Nd and Sr isotope constraints on
280
the origin of the Cornubian Batholith, SW England. J. Geol. Soc. London, 142,
281
1159-1177.
282
DePaolo, D.J., and G.J. Wasserburg (1976), Nd isotopic variations and
283
petrogenetic models, Geophys. Res. Lett., 3, 249-252.
284
Ercilla, G., Casas, D., Vázquez, J.T., Iglesias, J., Somoza, L., Juan, C., Medialdea,
285
T., León, R., Estrada, F., García-Gil, S., Farrán, M., Bohoyo, F., García, M., and
286
A. Maestro (2011), Imaging the recent sediment dynamics of the Galicia Bank
287
region (Atlantic, NW Iberian Peninsula). Mar. Geoph. Res., 32 I, 1–2, 99–126.
288
Galindo, C., Tornos, F., Darbyshire, D. P. F., and C. Casquet (1994), Sm/Nd dating
289
and isotope constraints for the origin of the barite-fluorite (Pb-Zn) veins of the
290
Sierra del Guadarrama (Spanish Central System, Spain). Chem. Geol., 112 (3-4),
291
351-364.
292
Groupe Galicia (1979), The continental margin off Galicia and Portugal: acoustical
293
stratigraphy, dredge stratigraphy and structural evolution. In: Sibuet JC, et al.
294
(Ed.), Init. Rep. DSDP 47. U.S. Goverment printing Office, Washington D.C., 633–
295
662
296
Malod, J. A., Murillas, J., Kornprobst ,J.,
297
lithosphere at the edge of a Cenozoic active continental margin (northwestern
298
slope of Galicia Bank, Spain). Tectonophysics, 221, 195-206.
299
Mauffret, A., and L. Montadert (1988), Seismic stratigraphy off Galicia. In:
300
Boillot, G., Winterer, E.L., et al. (Eds). Proc. ODP. Sci. Results, 103: 13–30.
301
Murillas, J., Mougenot, D., Boillot, G., Comas, M. C., Banda E., and A. Mauffret
302
(1990), Structure and evolution of the Galicia Interior Basin (Atlantic western
303
Iberian continental margin). Tectonophysics, 184, 297-319.
304
Cande, S. and D. Kent (1992), A new geomagnetic polarity time scale for the late
305
Cretaceous and Cenozoic, J. Geophys. Res., 97, 13917-13951.
306
Somoza, L., Ercilla, G., Urgorri, V., León, R., Medialdea, T., Paredes, M.,
307
González, F. J., and M. A. Nombela (2014), Detection and mapping of cold-water
308
coral mounds and living Lophelia reefs in the Galicia Bank, Atlantic NW Iberia
309
margin. Mar. Geol., 349, 73-90.
310
Sibuet, J. C. (1992), New Constraints on the formation of the nonvolcanic
311
continental Galicia-Flemish Cap conjugate margins. J. Geol. Soc., 149, 829-840.
312
Thinon, I. (1999), Structure profonde de la Marge Nord Gascogne et du Bassin
313
Armoricain, Université de Bretagne Occidentale, Brest, 327 pp.
314
Vázquez, J.T., Medialdea, T., Ercilla, G., Somoza, L., Estrada, F., Fernández-
315
Puga, M.C., Gallart, J., Gràcia, E., Maestro, A., and M. Sayago (2008), Cenozoic
and G. Boillot (1993), Oceanic
316
deformational structures on the Galicia Bank Region (NW Iberian continental
317
margin).
Mar.
Geol.,
249
(1–2),
128–149.
Al
Pearson Correlation
Al
1
.634
.113
K
.875*
Na
.643
Ca
-.779
Mg
.936**
Ti
.624
Si
Pearson Correlation
.634
1
-.086
.904*
.120
-.034
.378
P
Pearson Correlation
.113
-.086
1
.031
.798
-.278
K
Pearson Correlation
.875*
.904*
.031
1
.412
Na
Pearson Correlation
.643
.120
.798
.412
Ca
Pearson Correlation
-.779
-.034
-.278
324
Mg
Pearson Correlation
.936**
.378
325
Ti
Pearson Correlation
.624
Fe
Pearson Correlation
Mn
Pearson Correlation
318
319
320
321
Si
P
Fe
.565
Mn
.726
.499
-.178
-.041
-.014
.722
.271
.076
-.396
.693
.581
.173
.308
1
-.777
.578
.827*
.688
.612
-.396
-.777
1
-.860*
-.514
-.931**
-.959**
-.014
.693
.578
-.860*
1
.389
.655
.882*
.499
.722
.581
.827*
-.514
.389
1
.416
.308
.565
-.178
.271
.173
.688
-.931**
.655
.416
1
.857*
.726
-.041
.076
.308
.612
-.959**
.882*
.308
.857*
1
322
323
326
327
328
329
330
Table S1: Pearson correlation matrix for major elements contained in the phosphorites from Galicia Bank region, n=6.
331
* The correlation is significant at the 0.05 level. ** The correlation is significant at the 0.01 level.
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
Sample
DRR81-5 (N= 3)
Mean
Max
Al2O3
FeO
CaO
MgO
MnO
P2O5
K2O
Na2O
SiO2
TiO2
SO3
F
Cl
SrO
BaO
0.64
0.95
0.44
0.64
50.73
51.74
0.25
0.31
0.16
0.45
31.28
31.85
0.12
0.19
0.86
0.92
1.63
2.48
0.11
0.16
1.35
1.41
3.45
3.59
<DL
0.03
<DL
0.13
0.31
0.92
Min
0.31
0.19
48.80
0.17
<DL
30.43
0.04
0.73
0.58
0.05
1.32
3.29
<DL
<DL
<DL
DRR47-1 (N= 4)
Mean
Max
0.82
1.05
1.14
3.94
49.82
51.92
0.63
0.88
0.20
0.63
30.28
30.58
0.17
0.23
0.91
1.01
2.94
3.97
<DL
0.12
1.24
1.35
3.31
3.35
<DL
0.02
<DL
0.05
<DL
0.03
Min
0.48
0.11
47.87
0.45
<DL
29.75
0.08
0.86
1.65
<DL
1.12
3.27
<DL
<DL
<DL
DRR47-2 (N= 7)
Mean
Max
0.87
2.14
0.37
0.89
50.28
53.19
0.29
0.47
0.06
0.39
32.33
34.28
0.07
0.21
0.78
0.85
1.94
4.21
0.33
2.15
1.13
1.21
3.51
4.09
<DL
<DL
<DL
0.10
<DL
0.09
Min
0.32
0.17
48.17
0.14
<DL
30.73
<DL
0.66
0.55
<DL
1.01
3.05
<DL
<DL
<DL
DRR47-2-3
2.53
7.65
9.07
1.63
15.43
5.02
0.52
0.76
4.46
0.22
0.35
0.53
0.60
<DL
0.30
DRR47-2-4
2.02
5.75
6.90
4.12
49.69
3.67
0.81
1.06
0.52
0.26
0.19
0.24
0.09
0.11
1.47
DRR47-2-12
DRR38-2a (N= 8)
Mean
Max
0.86
2.60
45.10
1.11
7.57
26.58
0.09
0.93
0.20
<DL
1.00
2.94
0.04
0.20
0.18
0.72
2.38
3.53
5.25
49.65
56.09
0.51
0.66
2.81
5.76
28.39
30.29
0.11
0.36
0.86
0.97
1.09
4.99
nd
nd
nd
nd
3.45
4.15
0.10
0.19
0.19
0.23
0.07
0.14
357
Min
0.10
0.55
47.29
0.14
0.45
27.27
<DL
0.78
0.16
nd
nd
3.03
0.02
<DL
<DL
358
DRR38-2b (N= 4)
Mean
Max
0.25
0.51
0.24
0.44
50.69
57.18
0.42
0.56
0.08
0.26
28.51
32.27
0.03
0.13
0.98
1.23
0.37
0.92
nd
nd
nd
nd
3.05
3.44
0.08
0.11
0.26
0.38
<DL
<DL
Min
0.03
0.08
47.45
0.32
<DL
24.03
<DL
0.61
<DL
nd
nd
2.52
0.05
0.11
<DL
DRR38-2c (N= 2)
Fe-Mn ox. layer
Max
2.13
47.77
9.49
2.53
37.13
3.12
0.5
1.2
2.95
nd
nd
0.23
0.68
0.17
1.73
Min
1.22
16.21
5.33
1.43
13.21
3.1
0.1
0.6
1.33
nd
nd
0.18
0.64
<DL
0.32
347
348
349
350
351
352
353
354
355
356
359
360
361
362
363
Table S2: Phosphorite mineralizations using EPMA: DRR81-5 and DRR47-1: CFA in phosphorite slabs. DRR47-2: CFA in phosphorite pebbles.
364
DRR47-2-(3, 4, 12): Fragmented phosphorite with replacement by Fe-Mn oxyhydroxides. DRR38-2a: CFA in phosphorite nodule layers. DRR38-2b:
365
CFA in phosphorite nodule nucleus. DRR38-2c: Fe-Mn oxyhydroxides in phosphorite nodule layers. <DL: below detection limit. Nd: not determined.
Sample
DRR47-1 (N= 4)
Mean
Max
Min
DRR47-2 (N= 4)
Mean
Max
Min
DRR81-1 (N= 9)
Mean
Max
Min
DRR81-1-4 (Co-rich ox)
DRR81-1-8 (Mn-carb)
DRR38-5 (N= 6)
Mean
Max
Min
DRR38-8-5
DRR38-8-6
DRR81-5-5
DRR81-5-4 (ox. movil.)
Al2O3
FeO
CaO
MgO
MnO
P2O5
K2O
Na2O
SiO2
TiO2
SO3
F
Cl
Sr
Ba
Ni
Co
Cu
Pb
Zn
Mo
5.32
7.06
2.69
5.92
15.35
0.10
1.79
2.23
1.17
8.33
11.02
4.47
45.86
50.98
41.17
0.32
0.63
0.13
0.41
0.50
0.31
1.22
1.49
1.10
1.13
2.23
0.16
0.24
0.35
0.12
0.24
0.33
0.14
<DL
<DL
<DL
0.05
0.07
0.04
0.08
0.12
0.06
0.40
0.98
0.14
1.93
2.97
0.89
0.78
1.31
0.17
0.23
0.27
0.19
0.39
0.67
0.11
0.24
0.29
0.16
0.13
0.18
0.07
151
513
3
3.37
6.54
1.47
30.22
60.43
4.99
1.76
2.80
0.85
2.31
2.88
1.74
22.23
56.81
0.50
1.23
2.36
0.22
0.46
0.92
0.13
0.72
1.18
0.22
2.49
4.00
0.53
0.30
0.47
0.19
0.24
0.30
0.15
<DL
<DL
<DL
0.33
0.90
0.05
0.37
0.37
0.37
1.53
5.30
0.06
0.38
0.57
0.24
0.12
0.16
0.10
0.16
0.20
0.12
0.13
0.17
0.08
0.19
0.25
0.13
<DL
<DL
<DL
4
11
0.01
0.81
1.33
0.18
2.48
1.49
0.29
0.57
0.10
0.22
0.14
5.66
26.49
0.86
2.16
38.01
3.10
3.84
2.60
5.87
3.21
53.23
60.73
28.81
50.62
14.48
0.26
0.79
0.05
0.09
1.01
0.91
1.12
0.46
0.90
0.12
1.46
1.91
0.82
1.97
0.75
0.41
1.12
0.08
0.13
0.08
<DL
<DL
<DL
nd
nd
<DL
<DL
<DL
nd
nd
0.10
0.12
0.09
0.18
0.11
0.12
0.20
0.03
0.07
0.08
0.23
0.33
0.17
0.09
0.11
3.29
6.58
1.65
0.56
0.39
0.24
0.40
0.09
1.20
0.53
1.59
2.10
0.57
5.61
2.11
0.15
0.19
0.10
<DL
<DL
<DL
<DL
<DL
nd
nd
<DL
<DL
<DL
nd
nd
<DL
<DL
<DL
nd
nd
241
637
100
226
103
0.70
1.35
0.09
8.18
4.19
5.44
4.30
69.12
75.37
62.63
14.09
19.99
13.90
0.87
0.80
3.47
0.20
1.01
2.49
2.77
1.12
3.13
4.99
2.30
12.25
6.08
6.53
10.20
0.44
1.02
0.08
33.10
22.24
27.42
53.76
0.75
1.04
0.56
0.78
1.17
0.87
0.10
0.07
0.11
0.02
0.12
0.15
0.23
1.00
0.23
0.40
0.16
0.75
1.17
1.05
1.21
2.38
2.83
1.81
1.42
1.60
1.01
0.28
<DL
<DL
<DL
nd
nd
0.73
0.07
<DL
<DL
<DL
nd
nd
0.94
0.17
<DL
<DL
<DL
<DL
<DL
<DL
<DL
0.23
0.55
0.10
0.68
1.72
0.35
0.07
<DL
<DL
<DL
<DL
<DL
0.08
0.06
0.06
0.06
0.06
<DL
0.10
0.10
0.15
<DL
<DL
<DL
1.06
0.51
0.83
0.87
0.10
0.10
0.10
0.62
1.12
0.87
0.23
<DL
<DL
<DL
<DL
<DL
<DL
0.53
<DL
<DL
<DL
nd
nd
0.16
0.08
<DL
<DL
<DL
nd
nd
<DL
0.15
<DL
<DL
<DL
nd
nd
0.08
<DL
0.02
0.02
0.01
1
1
2
61
366
367
Table S3: Fe-Mn oxyhydroxides using EPMA: DRR47-1: Transitional hydrothermal-hydrogenetic oxyhydroxides in a partly replaced phosphorite
368
slab. DRR47-2: Replacement by Fe-Mn oxyhydroxides in a fragmented phosphorite. DRR81-1: 10 Å manganates in a Co-rich Mn nodule. DRR81-1-
369
4: Co-Ni fibrous manganate. DRR81-1-8: Mn-rich carbonate layer. DRR38-5: Goethite in a Fe-rich nodule. DRR38-8-(5, 6) and DRR81-5-5:
370
Hydrogenetic oxyhydroxides in Fe-Mn crusts. DRR81-5-4: Mg-rich Mn oxide formed by diagenetic remobilization. <DL: below detection limit. Nd:
371
not
determined.
Mn/Fe