 | | Report (volume) | | massive sulfide mound in the NESCA area in the Escanaba Trough , offshore of northern California, depth 3232...Diffuse venting of hydrothermal fluid through pyrrhotite-rich massive sulfide rubble supports a hydrothermal...Hydrothermal, and Biologic Studies at Escanaba Trough, Gorda Ridge, Offshore Northern California JANET...hydrothermal, and biologic studies at Escanaba Trough, Gorda Ridge, offshore northern California I Janet...references. 1. Geology-Escanaba Trough. 2. Hydrothermal vents-Escanaba Trough. 3. Hydrothermal vent faunaEscanaba |  | | Report (chapter) | | sulphide deposits at the Middle Valley and Escanaba Trough spreading centres: ODP Leg 169 R. H. J A M...drilled during Ocean Drilling Program Leg 169 at two locations along the Juan de Fuca/Gorda spreading centres...impregnations and cross-cutting copper-rich veins. Ridge-parallel normal faulting is probably involved in...recovered from the Central Hill hydrothermal site, Escanaba Trough, suggests mineralization forms only a thin...formation of a large ore deposit in this area. Ocean Drilling Program (ODP) Leg 169 was the second leg |  | Von Damm, K.L., Parker, C.M., Zierenberg, R.A., Lilley, M.D., Olson, E.J., Clague, D.A., McClain, J.S. (2005) The Escanaba Trough, Gorda Ridge hydrothermal system: Temporal stability and subseafloor complexity. Geochimica et Cosmochimica Acta, 69 (21) 4971-4984 doi:10.1016/j.gca.2005.04.018 | Journal (article/letter/editorial) | | doi:10.1016/j.gca.2005.04.018 The Escanaba Trough, Gorda Ridge hydrothermal system: Temporal stability... OLSON,3 D. A. CLAGUE,4 and J. S. MCCLAIN2 1 Complex Systems Research Center, Institute for the Study...from the active hydrothermal system in Escanaba Trough, Gorda Ridge in 2000 and 2002 remain unchanged from...chemistry of the hydrothermal system are much more complex within the sediment cover than would be expected...whether the system had evolved since 1988. Escanaba Trough is one of only four active hydrothermal systems |  | Clague, D.A., Friesen, Walter, Quinterno, Paula, Morgensson, L.A., Holmes, Mark L., Morton, Janet, Bouse, Robin M., Davis, Alice (1984) Preliminary geological, geophysical, and biological data from the Gorda Ridge. Open-File Report Vol. 1984 (84-364) US Geological Survey doi:10.3133/ofr84364 | Report (issue) | | Geological, Geophysical, and Biological Data from the Gorda Ridge by David Clague, Walter Friesen, Paula Quinterno...Survey editorial standards INTRODUCTION The Gorda Ridge, an oceanic spreading center with a full-spreading...coast of northern California and southern Oregon (Figure 1). The ridge consists of three segments of ridgecrest...the ridge at about 42°N. The entire Gorda Ridge is only about 160 n. miles long and the southern 50 n...miles of the ridge is covered by turbidites. This section is called the Escanaba Trough. Morphologically |  | | Journal (article/letter/editorial) | | Association in Pyrrhotite-Rich Massive Sulfide Deposits, Escanaba Trough, Southern Gorda Ridge TUOMO O. TÖRMÄNEN*...in pyrrhotite-rich massive sulfide samples from the sediment-covered floor of the Escanaba trough, the...the slow-spreading, southernmost segment of Gorda Ridge. These concentrations reflect the presence of...flaky morphology and occur in samples in which pyrrhotite is oxidized and replaced by Fe oxyhydroxides...and sulfur. Mounds and chimneys dominated by pyrrhotite and containing lesser amounts of isocubanite |  | | Journal (article/letter/editorial) | | smectite and chlorite groups (McMurtry and Yeh, 1981; De Carlo et al., 1983; McMurtry et al., 1983; 1993;...the ridge-transform intersection between the St. Paul Fracture Zone (FZ) and Intra-Transform Ridge Segment...Segment “A” at the Mid-Atlantic Ridge (D'Orazio et al., 2004). The sample was dredged from the summit area...on the southern summit bench of the Red Seamount, a tholeiitic off-axial seamount at 21°N East Pacific...Pacific Rise (EPR) (Alt et al., 1987). Samples from basalt-hosted sediment-covered hydrothermal systems were |  | Bogdanova, O. Yu., Lein, A. Yu., Dara, O. M., Ozhogina, E. G., Lisitzin, A. P. (2016) Pyrrhotite mineralization as a search criterion for sulfide deposits at sediment-covered spreading centers. Doklady Earth Sciences, 470 (1) 928-932 doi:10.1134/s1028334x16090038 | Journal (article/letter/editorial) | | 2016, Vol. 470, No. 1, pp. 72–76. GEOCHEMISTRY Pyrrhotite Mineralization as a Search Criterion for Sulfide...Abstract—Pyrrhotite ores forming the hydrothermal vents of the Hydrothermal Hills in the Southern Trough...sulfide deposits of pyrrhotite mineralization was revealed: the presence of pyrrhotite associations to hydrocarbons...of Cu, Zn, and Pb; the enrichment of sulfur of pyrrhotite and hydrogen sulfide of hydrothermal solutions...1134/S1028334X16090038 By the northern course of the East Pacific Rise (EPR), three sulfide deposits were found on |  | | Journal (article/letter/editorial) | | Valley massive sulphide deposit, northern Juan de Fuca Ridge: Pb isotope constraints Finlay M. Stuart... Scottish UniÕersities Research Reactor Centre, East Kilbride G75 0QF, UK b Department of Earth Sciences...deposit during Ocean Drilling Program Leg 139 at Middle Valley, northern Juan de Fuca Ridge, have 206 Pbr204...measured in hydrothermal sulphides from the East Pacific Ocean. 206 Pbr204 Pb ratios overlap the range of...local nature of hydrothermal circulation at mid-ocean ridges. The 3 Her4 He of hydrothermal fluids in |  | Zierenberg, Robert A., Koski, Randolph A., Morton, Janet L., Bouse, Robin M. (1993) Genesis of massive sulfide deposits on a sediment-covered spreading center, Escanaba Trough, southern Gorda Ridge. Economic Geology, 88 (8) 2069-2098 doi:10.2113/gsecongeo.88.8.2069 | Journal (article/letter/editorial) | | ghercontentsofZn, Pb,Ag, As,Sb,andSnthandoes pyrrhotite-richmassivesulfide.Polymetallicmassivesulfidehaslow...averagingmorethan1 g/t Au. Massivesulfidefromthe Escanaba troughis enrichedin groupIV, V, andVI elementsrelativeto...ZIERENBERG ET AL. die Valley (northernJuande Fuca Ridge),and the cino fracture zone on the south and...approxiaboutthe tectonicsettingsand the natureof ore- Escanaba formingprocesses inancientpalcorift,sediment-dom-...inantenvironments. Data fromthe Escanaba trough, hough,1980; Wilson,1989). The Escanaba consistent with the slow-spreading |  | | Report (issue) | | SULFIDE SAMPLES DREDGED IN 1986 FROM ESCANABA TROUGH, SOUTHERN GORDA RIDGE Laura M. Benninger1 Randolph A...dredged in 1986 from Escanaba Trough, the sediment-covered southern end of Gorda Ridge (Figure 1). The dredge...characteristics of two locations in Escanaba Trough were investigated: the southern or SESCA site at 40°45'N latitude...seismic-reflection and photographic survey in Escanaba Trough (Morton et al., 1987b). Volcanic edifices that...gravity core and water column sampling in Escanaba Trough, are reported in Morton et al., 1987b. High |  | | Journal (article/letter/editorial) | | S0016-7037(01)00660-3 Metal mobility in sediment-covered ridge-crest hydrothermal systems: Experimental and theoretical...sedimentary organic matter blanketing midocean ridge crests has a potentially strong impact on metal...hemipelagic mud from Middle Valley, northern Juan de Fuca Ridge, with seawater and a Na-Ca-K-Cl fluid of...Basin, Gulf of California, and Escanaba Trough, southern Juan de Fuca Ridge, large sulfide deposits are...oceanic spreading centers. Hydrothermal activity in ridge-crest environments characterized by low sedimentation |  | | Journal (article/letter/editorial) | | Middle Valley Sulfide Deposits, Northern Juan de Fuca Ridge: Radiogenic Isotope Systematics T. BJERKGÅRD...sediment-filled rift valley at the northern Juan de Fuca Ridge, are among the largest and richest sulfide...deposits on the modern sea floor. Drilling during Ocean Drilling Program Leg 169 allowed a complete hydrothermal...rift valley at the northernmost end of the Juan de Fuca Ridge, about 150 km † Corresponding author: e-mail...Goodfellow and Blaise, 1988) and has been drilled by the Ocean Drilling Program on two occasions, during Leg 139 |  | Zeng, Zhigang, Ma, Yao, Chen, Shuai, Selby, David, Wang, Xiaoyuan, Yin, Xuebo (2017) Sulfur and lead isotopic compositions of massive sulfides from deep-sea hydrothermal systems: Implications for ore genesis and fluid circulation. Ore Geology Reviews, 87. 155-171 doi:10.1016/j.oregeorev.2016.10.014 | Journal (article/letter/editorial) | | fields in the East Pacific Rise (EPR), Mid-Atlantic Ridge (MAR), Central Indian Ridge NU (CIR), Southwest...Southwest Indian Ridge (SWIR), and North Fiji Basin (NFB). The sulfur MA isotopic compositions of the...sub-seafloor hydrothermal systems in sediment-free mid-ocean ridges and mature back-arc basins. Furthermore,...minerals in the super-fast and fast spreading mid-ocean ridges (MORs) exhibit less spread in their the δ34S...from modern seafloor hydrothermal systems in mid-ocean ridges (MORs) D and back-arc basins (BABs) have |  | | Journal (article/letter/editorial) | | various geological settings, including the Okinawa Trough (sediment-rich Hakurei and sediment-poor NU Jade...Vienna MA Woods fields), and the Central Indian Ridge (mafic/ultramafic-hosted Kairei and basalt-hosted...mmol/kg, which sufficiently lowers fO2-fS2 to the pyrrhotite stability field; however, low H2S concentrations...calculations at 350°C indicate that neither pyrite nor pyrrhotite is stable in the initial hot fluids of the TAG...TAG and ultramafic-hosted Mid-Atlantic Ridge systems due to the low H2S concentrations. With 2 ACCEPTED |  | | Journal (article/letter/editorial) | | hydrothermal JADE field in the Okinawa back-arc trough Received: 5 October 1995 / Accepted: 10 May 1996...isotope signatures of VMS-type deposits at mid-ocean ridges is distinctly different. In the absence of...The JADE field is located in the Okinawa back-arc trough, which extends from Kyushu to Taiwan (Fig. 1)....km in the NE (Kimura 1985). The central Okinawa trough consists of several segments which are aligned...barite increase together with realgar, orpiment, pyrrhotite, marcasite, stibnite, cinnabar, and Pb-As-sulfosalts |  | | Journal (article/letter/editorial) | | Environmental Sciences Division, Oak Ridge N ational Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6036 INTRODUCTION...be a relatively common phenomenon on the world ridge-crest system. It is a consequence of the emplacement...extending from the ridge axes (zero crustal age) to several thousand kilometers away on the ridge flank� (crustal...rates, at sediment-covered and sediment-starved ridge axes, and at temperatures ranging from just a few...systems. Not (21 °24'N, 38°03'E) and the Mariana Trough ( 1 8° 1 3'N, 144°4 1'E). shown are the Red Sea |  | | Report (issue) | | WITH SEDIMENT-HOSTED SULFIDES FROM ESCANABA TROUGH, SOUTHERN GORDA RIDGE Keith A. Kvenvolden John B. Rapp...submersible in Escanaba Trough, the sediment-covered, southern end of the Gorda Ridge spreading axis...molecular distributions of hydrocarbons in the two pyrrhotite-rich samples recovered by submersible are similar...with the hydrocarbon composition of the first pyrrhotite-rich sample containing petroleum discovered at...active Escanaba Trough. INTRODUCTION Escanaba Trough is the southern-most segment of the Gorda Ridge |  | Davis, A. S., Clague, D. A., Zierenberg, R. A., Wheat, C. G., Cousens, B. L. (2003) SULFIDE FORMATION RELATED TO CHANGES IN THE HYDROTHERMAL SYSTEM ON LOIHI SEAMOUNT, HAWAI'I, FOLLOWING THE SEISMIC EVENT IN 1996. The Canadian Mineralogist, 41 (2) 457-472 doi:10.2113/gscanmin.41.2.457 | Journal (article/letter/editorial) | | and sulfide crystals. The presence of wurtzite, pyrrhotite, and chalcopyrite indicate high-temperature fluids...(>250°C), the first such occurrence documented for an ocean-island volcano. The composition of the sulfide minerals...similar to that of sulfides from black smokers at mid-ocean ridges. Samples from barite-rich mounds, built after...plume, resemble white smoker deposits from mid-ocean ridges. The ␦34S of the sulfide is lower than that...des sulfates hydrothermaux dans les échantillons de sédiment prélevés lors d’une mission d’urgence au |  | | Journal (article/letter/editorial) | | Valley, Juan de Fuca Ridge DAMON A. H. TEAGLE† Southampton Oceanography Centre, School of Ocean and Earth...of the bare-rock Endeavour segment of the Juan de Fuca Ridge, is host to the base metal-rich (Cu-Zn) Bent...steep-sided body ~200 m across and ~100-m-thick. Ocean Drilling Program (ODP) hole 856H penetrates through...basalts, ~0.7), that mimic profiles for midocean ridge hydrothermal fluids, require fluid-rock exchange...vents or through more diffuse leakage. In contrast, ocean crust spreading close to sources of abundant clastic |  | | Report (issue) | | Mapping and Research: Working Together in the Pacific EEZ U.S. GEOLOGICAL SURVEY CIRCULAR 1092 AVAILABILITY...Mapping and Research: Working Together in the Pacific EEZ MILLINGTON LOCKWOOD, National Oceanic and Atmospheric...Mapping and Research : working together in the Pacific EEZ I Millington Lockwood and Bonnie A. McGregor...Includes bibliographical references. 1. Ocean bottom-Pacific Coast (U.S.)-Maps-Congresses. I. Lockwood...Program-Challenges and Choices John Carey 9 Mapping the Ocean Floor from the DMA-Defense Hydrographic Initiative |  | | Report (issue) | | Mineralogy of Sand in Turbidites from Escanaba Trough, Northeast Pacific Ocean by Florence L. Wong1 Open-File... MINERALOGY OF SAND IN TURBIDITES FROM ESCANABA TROUGH, NORTHEAST PACIFIC OCEAN Florence L. Wong U.S. Geological...Park, California INTRODUCTION The Escanaba Trough, southern Gorda Ridge, is a seafloor spreading center...susceptibility data on sediment cores from Escanaba Trough have placed the Holocene/Pleistocene boundary...detected on terraces uplifted on either side of Escanaba Trough as well as locally elevated sediment hills |  | Mills, R.A., Thomson, J., Elderfield, H., Hinton, R.W., Hyslop, E. (1994) Uranium enrichment in metalliferous sediments from the Mid-Atlantic Ridge. Earth and Planetary Science Letters, 124 (1) 35-47 doi:10.1016/0012-821x(94)00083-2 | Journal (article/letter/editorial) | | in metalliferous sediments from the Mid-Atlantic Ridge R.A. Mills a, J. Thomson b, H. Elderfield ‘, R...Previous studies of metal-rich sediments at mid-ocean ridge spreading centres have suggested that U/Fe ratios...to site. A suite of cores from the Mid-Atlantic Ridge has been analysed for U and Fe content and most...sediments have been observed throughout the mid-ocean ridge system [l-4], provide an areally important sink...0012-821X/94/$07.00 area at 26”N on the Mid-Atlantic Ridge in the 1970s [4,51 and have subsequently been studied |  | Morton, J.L., Normark, W.R., Ross, Stephanie L., Koski, R.A., Holmes, M.L., Shanks, Wayne C., Zierenberg, R.A., Lyle, M.W., Benninger, L.M. (1987) Preliminary report, cruises L1-86-NC and L2-86-NC, Escanaba Trough, Gorda Ridge. Open-File Report Vol. 1987 (87-375) US Geological Survey doi:10.3133/ofr87375a | Report (issue) | | report, cruises L1-86-NC and L2-86-NC, Escanaba Trough, Gorda Ridge Janet L. Morton , William R. Normark...sampled at the sediment-covered Escanaba Trough, southern Gorda Ridge, during S.P. Lee cruises L1-86-NC...within the sedimentary fill along the axis of Escanaba Trough. The sulfide and other hydrothermal minerals...depth. INTRODUCTION Gorda Ridge is located in the northeast Pacific Ocean 200 to 300 km west of northern...California and southern Oregon, within the U.S. Exclusive Economic Zone (EEZ). Escanaba Trough comprises the |  | | Journal (article/letter/editorial) | | Precipitation of gold during conductive cooling of mid-ocean ridge black smoker (MOR) fluids occurs at low temperatures...In this case, the lower stability of the AuHS° complex at low ƒO2 (buffered by fayalite, magnetite, and...aqueous species to very low temperatures. These complex systematics make prediction of Au and Ag grades...sebastian.fuchs@bgr.de 1 GEOMAR – Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1-3, 24148 Kiel,...1977 (Lonsdale 1977) and black smokers at East Pacific Rise a few years later (Francheteau et al. 1979; |  | | Journal (article/letter/editorial) | | Universities Research and Reactor Centre , Rankine Avenue, East Kilbride , G75 OQF, Scotland, United Kingdom Published...Universities Research and Reactor Centre, Rankine Avenue, East Kilbride, G75 OQF Scotland, United Kingdom Abstract...chalcopyrite, and locally contains abundant magnetite, pyrrhotite, and chromite. The gangue contains predominantly...continuation into the Bitlis and Zagros oceans (the southern branch of Neo-Tethys) began opening mainly during...represent relicts of the closed section of the southern branch of Neo-Tethys. Ophiolites in southeastern |
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