Sedimentology, Mineralogy, and Geochemistry of Green Clay Samples from the Galapagos Hydrothermal Mounds, Holes 506, 506C, and 507D, Deep Sea Drilling Project Leg 70 (Preliminary Data)

Honnorez, J.; Karpoff, Anne Marie; Trauth-Badaut, D.

doi:10.2973/dsdp.proc.70.109.1983

Cited by 22 publications

(21 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Octahedral and tetrahedral compositions were calculated assuming total structural iron to be present as Fe 3+, because the EDX analyses were unable to distinguish Fe 2+ from Fe 3+. This assumption, however, is reasonable because wet chemical analyses carried out on the <2-#m size fractions showed very little or no Fe 2+ (Honnorez et al, 1983).…”

Section: Methodsmentioning

confidence: 99%

“…These measure- Figure 1. Location of site 509B (Deep Sea Drilling Project leg 70) and schematic diagram of the internal structure and geometry ofa hydrothermal mound of the Galapagos Spreading Center (after Honnorez et al, 1983). ments indicated high and variable total heat flow, with local fluid discharges of about 30~ at -< 10 -s m/s (Becker et al, 1983).…”

Section: Geological Setting and Sample Selectionmentioning

confidence: 99%

“…The mounds are located in areas of high heat flow (8 to 10 heat flow units) above small, vertical basement faults (Williams et al 1974). Clay minerals in the Galapagos mounds were described by Hoffert et al (1980), Honnorez et al (1981Honnorez et al ( , 1983, Kurnosov et al (1983), and Varentsov et aL (1983) as Fe-rich smectite and Fe-rich mica, i.e., nontronite and celadonite, respectively. The origin and subsequent precipitation of these minerals from solutions exiting from a highly permeable ocean basement in the vent area was ascribed by Honnorrez eta[.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Fe-Smectite-Glauconite Transition in Hydrothermal Green Clays from the Galapagos Spreading Center

Buatier

Honnorez

Ehret

1989

Clays and clay miner.

View full text Add to dashboard Cite

Abstract--X-ray powder diffraction (XRD) and energy-dispersive X-ray analyses (EDX) of individual clay particles from hydrothermal mounds in the Galapagos spreading center (GSC) (Deep Sea Drilling Project, hole 509B) and high-resolution transmission electron microscopy (HRTEM) of the <2-urn size fraction of these sediments were carried out to document the mineralogy, geochemistry, and evolution of their clay horizons. The hydrothermal clay minerals of the GSC mounds were found to be intercalated with pelagic sediments and occurred as irregular interstratified illite/smectite according to X-ray powder diffraction analyses. On the basis ofTEM, HRTEM, and EDX data, two types of clays appeared to coexist; these types differed in morphology, potassium content, and mode of stacking sequence. Lath-shaped particles having regular 10-~, spacings were identified as glauconite, and filmy or veil-like particles, having curly edges and variable 10-13-fk spacings were identified as Fe-smectite (nontronite and Fe-montmorillonite). The absence of lattice fringes between Fe-smectite and glauconite crystallites was observed by HRTEM in clay aggregates. This structural discontinuity between Fe-smectite and glauconite layers suggests that a dissolution-recrystallization mechanism was responsible for the textural and chemical transition from the filmy Fe-smectite to the lath-like glauconite.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Geological Setting and Sample Selectionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Fe-Smectite-Glauconite Transition in Hydrothermal Green Clays from the Galapagos Spreading Center

Buatier

Honnorez

Ehret

1989

Clays and clay miner.

View full text Add to dashboard Cite

show abstract

“…These deposits usually form at redox boundaries within the sediment or at the sediment-water interface. The third category of deposits precipitates from discharging hydrothermal fluids close to the ridge-axis, or on ridge flanks with a thin sedimentary cover (Honnorez et al, 1983;Buatier et al, 1995;Buatier et al, 2000).…”

Section: Introductionmentioning

confidence: 99%

Characterization of metalliferous sediment from a low-temperature hydrothermal environment on the Eastern Flank of the East Pacific Rise

et al. 2008

View full text Add to dashboard Cite

Metalliferous deposits are described from the eastern flank of the East Pacific Rise (EPR) offshore Costa Rica, close to a basaltic seamount called "Dorado high".Based on heat-flow data and porewater profiles, the site is an area of active low temperature hydrothermal discharge. We focus on the mineralogical and chemical analyses from a 124 cm long gravity core (GC50), located on the north-western slope of the 100 m high Dorado high. In this core, the sediments consist of detrital clay minerals as well as authigenic minerals such as zeolites, apatites, and Fe/Mn-rich oxyhydroxides. In contrast, the reference sediments from adjacent areas without hydrothermal activity are olive gray hemipelagic muds composed of volcanic glass particles, clay minerals, siliceous microfossils, and some detrital quartz and feldspar.Bulk sediment chemistry and chemical enrichment factors calculated with respect to the reference sediment indicate that the most important chemical changes occurred at the base of the core from 100 to 124 cm bsf, with strong enrichments in MnO, CaO, P 2 O 5 , and Fe 2 O 3 . These enrichments are correlated with the occurrence of authigenic Fe-oxyhydroxide (goethite) and Mn oxide (todorokite and vernadite, at 100 cm bsf), and hydrothermal apatite (110-124 cm bsf). In the upper section of the core from 12 to 70 cm, the sediment is composed of abundant smectite and authigenic phillipsite, and only minor chemical changes can be observed with respect to the reference sediments.The ubiquitous presence of phillipsite suggests that the entire sedimentary column of core GC50 was first affected by diagenesis. However, below 70 cm bsf, these phillipsites are partially dissolved and Fe oxides occur from 110 to 124 cm, followed 2 upward by Mn oxides at 100 cm. This transition from Fe to Mn rich sediments can be interpreted in terms of an upward increasing redox potential. PAAS-normalized REE patterns of GC50 sediments present clearly negative Ce and positive Y anomalies inherited from seawater at the base of core GC50. These anomalies decrease upward, which we interpret together with the transition from Fe to Mn-rich sediments by an upward migrating low temperature hydrothermal fluid. Thus, after a first stage of diagenesis, the discharge of a low temperature hydrothermal fluid occurred through the sedimentary column, leading to the precipitation of hydrothermal compounds that are lacking towards the surface.

show abstract

“…Crystallochemical investigations of these Fe-rich clays have revealed mixed-layer minerals composed of smectite and illite (Hoffert et al, 1978;Honnorez et al, 1983), Al-poor nontronite (Murnane & Clague, 1983;McMurty et al, 1983), or smectite "close to the pure Fe 3+ end-member of the nontronite-beidellite series" (Singer et al, 1984). Clay minerals approaching ferripyrophyllite (Chukbrov et al, 1978a) have never been identified in an ocean environment.…”

mentioning

confidence: 99%

Ferripyrophyllite and related Fe³⁺-rich 2:1 clays in Recent deposits of Atlantis II Deep, Red Sea

1992

View full text Add to dashboard Cite

Iron-rich dioctahedral 2:1 clays were sampled in metalliferous sediments from Atlantis II Deep (Red Sea), and studied by XRD, TEM, FTIR and Mössbauer spectroscopy. One sample with the structural formula (Si3·94Fe3+0·06)(Fe3+1·90Mg0·10)K0·1(Mg, Ca)0·03 is closer to the theoretical end-member ferripyrophyllite Si4Fe3+2O10(OH)2 than any other Fe-rich clay previously described. Other samples appear as mixed-layered clays: ferripyrophyllite-hydroferripyrophyllite or hydroferripyrophyllite-celadonite.

show abstract

Sedimentology, Mineralogy, and Geochemistry of Green Clay Samples from the Galapagos Hydrothermal Mounds, Holes 506, 506C, and 507D, Deep Sea Drilling Project Leg 70 (Preliminary Data)

Cited by 22 publications

References 12 publications

Fe-Smectite-Glauconite Transition in Hydrothermal Green Clays from the Galapagos Spreading Center

Fe-Smectite-Glauconite Transition in Hydrothermal Green Clays from the Galapagos Spreading Center

Characterization of metalliferous sediment from a low-temperature hydrothermal environment on the Eastern Flank of the East Pacific Rise

Ferripyrophyllite and related Fe³⁺-rich 2:1 clays in Recent deposits of Atlantis II Deep, Red Sea

Contact Info

Product

Resources

About

Sedimentology, Mineralogy, and Geochemistry of Green Clay Samples from the Galapagos Hydrothermal Mounds, Holes 506, 506C, and 507D, Deep Sea Drilling Project Leg 70 (Preliminary Data)

Cited by 22 publications

References 12 publications

Fe-Smectite-Glauconite Transition in Hydrothermal Green Clays from the Galapagos Spreading Center

Fe-Smectite-Glauconite Transition in Hydrothermal Green Clays from the Galapagos Spreading Center

Characterization of metalliferous sediment from a low-temperature hydrothermal environment on the Eastern Flank of the East Pacific Rise

Ferripyrophyllite and related Fe3+-rich 2:1 clays in Recent deposits of Atlantis II Deep, Red Sea

Contact Info

Product

Resources

About

Ferripyrophyllite and related Fe³⁺-rich 2:1 clays in Recent deposits of Atlantis II Deep, Red Sea