Results 61 to 70 of about 6,547 (194)

Petrological variability of recent magmatism at Axial Seamount summit, Juan de Fuca Ridge

Geochemistry, Geophysics, Geosystems, 2013
A combined study of mapping, observational, age constraint, and geochemical data at the summit of Axial Seamount, Juan de Fuca Ridge, has revealed its recent petrological history. Multiple basalt types erupted at the summit in a time sequence.
Brian M. Dreyer, David A. Clague, James B. Gill   +2 more
doaj   +1 more source

Juan de Fuca Ridge atlas, SeaMARC II acoustic imagery

, 1984
This open file comprises approximately 15,000 km2 of SeaMARC II side-scan acoustic imaging data from the northern Juan de Fuca and Explorer Ridges. These data are presented in two formats: a mosaic at a scale of 1:250,000 and individual swath images (10 km x 12 km) at a scale of 1:50,000.
E E Davis, R G Currie, B S Sawyer, D M Hussong   +3 more
openaire   +1 more source

Cores drilled into active smokers on Juan de Fuca Ridge

Eos, Transactions American Geophysical Union, 1992
The October 1991 Chronology expedition to the Endeavour Segment of the Juan de Fuca Ridge sought to exploit shipboard and land‐based radioisotope analyses based on detailed geological observations and comprehensive sampling to determine the absolute ages of an actively venting ridge‐axis hydrothermal field.
Debra Stakes, Willard S. Moore, Tom Tengdin, Leon Holloway, Meg Tivey, Mark Hannington, John Edmond, James F. Todd   +7 more
openaire   +1 more source

Sulfide geochronology along the Endeavour Segment of the Juan de Fuca Ridge [PDF]

, 2013
Forty-nine hydrothermal sulfide-sulfate rock samples from the Endeavour Segment of the Juan de Fuca Ridge, northeastern Pacific Ocean, were dated by measuring the decay of 226Ra (half-life of 1600 years) in hydrothermal barite to provide a history of ...
Alt, Ark, Baker, Bohnenstiehl, Butterfield, Butterfield, Carbotte, Carbotte, Cherkashov, Clague, Converse, Damm, David A. Clague, Davis, Davis, Deborah S. Kelley, Delaney, Delaney, Ditchburn, Ditchburn, Embley, Glickson, Glickson, Goldstein, Grasty, Hannington, Hannington, Hooft, James F. Holden, John R. Delaney, John W. Jamieson, Johnson, Johnson, Kadko, Kadko, Kappel, Karsten, Kelley, Kelley, Kelley, Kim, Kreemer, Kristall, Kristall, Kuznetsov, Kuznetsov, Lalou, Lalou, Lalou, Lalou, Lalou, Langmuir, Larson, Lilley, Linda E. Kimpe, Lowell, Macdonald, Margaret K. Tivey, Mark D. Hannington, Moore, Munch, Petersen, Proskurowski, Reyes, Riddihough, Robigou, Ronde, Ronde, Seyfried, Shilov, Solomon, Sours-Page, Stakes, Tivey, Tivey, Volpe, Wang, Wilcock   +77 more
core   +1 more source

Activity and phylogenetic diversity of sulfate-reducing microorganisms in low-temperature subsurface fluids within the upper oceanic crust

Frontiers in Microbiology, 2015
The basaltic ocean crust is the largest aquifer system on Earth, yet the rates of biological activity in this environment are unknown. Low-temperature (
Alberto eRobador, Sean Patrick Jungbluth, Doug eLaRowe, Robert eBowers, Michael eRappe, Jan eAmend, James eCowen   +6 more
doaj   +1 more source

Hydrothermal circulation at the Cleft-Vance overlapping spreading center : results of a magnetometric resistivity survey [PDF]

, 1998
We report on a magnetometric resistivity sounding carried out in the overlapping spreading center between the Cleft and Vance segments of the Juan de Fuca Ridge.
Adams, Adams, Alt, Archie, Baker, Baker, Becker, Becker, Bischoff, Chadwick, Chave, Christeson, Constable, Cox, Delaney, Edwards, Embley, Embley, Evans, Evans, Evans, Haymon, Kappel, Kappel, Kelley, Kent, Khamla Sananikone, Lonsdale, Macdonald, Marion Jegen, McDonald, Morton, Nehlig, Nehlig, Nesbitt, Nobes, Nobes, Pezard, Quist, Rob L. Evans, Rosenberg, Sleep, Sohn, Spahr C. Webb, Stevenson, Tivey, Travis, Wilcock, Wolfgram, Yang, Young   +50 more
core   +1 more source

Seismic anisotropy of the shallow crust at the Juan de Fuca Ridge [PDF]

Geophysical Research Letters, 2000
Microearthquake data recorded on four ocean bottom seismometers are used to study shear‐wave splitting on the Endeavour Segment of the Juan de Fuca Ridge. The covariance matrix decomposition method is used to determine the sensor orientation from explosive shot data and to estimate the anisotropy parameters for 238 earthquake records.
Almendros González, Francisco Javier, Barclay, Andrew H., Wilcock, William S. D., Purdy, M.   +3 more
openaire   +2 more sources

Sulfur isotope rations of sulfide minerals from the deposit of the Tsuchikura mine, Shiga Prafecture, Japan [PDF]

, 1998
Sulfur isotope rations of sulfide minerals in the ore specimens from the deposit of the Tsuchikura mine are distrib-uted in a range from -0.8 to 5.4%, mostly from +0.5 to 3.0%, close to the previous data (from +1 to +3%) by Miyake and Sasaki (1980).
Harada, Kaori, Kase, Katsuo, Yamamoto, Masahiro   +2 more
core   +1 more source

Distribution of hydrothermal manganese over the Juan De Fuca Ridge

Geophysical Research Letters, 1981
Bottom waters from five hydrographic stations, spaced equally along a 400‐km section of the Juan de Fuca Ridge north of the Blanco Fracture Zone, contain anomalously high concentrations of total dissolvable manganese (TDM). The two bottom‐most bottles from each hydrocast (∼ 100 to 200 m above bottom) range from 8.3 to 108.9 nmol kg−1 with a median ...
C. J. Jones, H. P. Johnson, J. R. Delaney   +2 more
openaire   +1 more source

Hot Rocks and Massive Sulfide: Northern Juan de Fuca Ridge.

Eos, Transactions American Geophysical Union, 1992
Leg 139 of the Ocean Drilling Program (ODP), completed on September 11, was the first part of a proposed two‐leg program to investigate hydrothermal processes and products at seafloor‐spreading centers covered with sediment. Sedimented spreading centers are unique and provide ideal targets for drilling; a regionally continuous, relatively impermeable ...
BONI, MARIA, Ocean Drilling Program Leg 139 Scientific Party   +1 more
openaire   +3 more sources