Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Space-time relations of hydrothermal sulfide-sulfate-silica deposits at the northern Cleft Segment, Juan de Fuca Ridge

Conference · · Geological Society of America, Abstracts with Programs; (United States)
OSTI ID:5067396
;  [1];  [2];  [3];  [4]
  1. Geological Survey, Menlo Park, CA (United States)
  2. PMEL/NOAA, Newport, OR (United States)
  3. Geological Survey of Canada, Ottawa, Ontario (Canada)
  4. Univ. of Miami, FL (United States). Rosenstiel School of Marine and Atmospheric Science
+ Show Author Affiliations
Submersible investigations along the northern Cleft Segment of the Juan de Fuca Ridge indicate that a newly erupted sheet flow and two recent megaplume events are spatially related to a NNE-trending fissure system that is now the locus for active hydrothermal venting and deposition of massive sulfide mounds and chimneys. Samples from active high-temperature vent sites located east and north of the sheet flow terrain include zoned Cu-sulfide-rich chimneys (Type 1), bulbous anhydrite-rich chimneys (Type 2), and columnar Zn-sulfide-rich chimneys (Type 3). Type 1 chimneys with large open channelways result from the focused discharge of fluid at temperatures between 310 and 328 C from the Monolith sulfide mound. Type 2 chimneys are constructed on the Monolith and Fountain mounds where discharge of fluid at temperatures between 293 and 315 C is diffuse and sluggish. Type 3 chimneys, characterized by twisting narrow channelways, are deposited from focused and relatively low-temperature fluid discharging directly from basalt substrate. Inactive sulfide chimneys (Type 4) located within 100 m of the fissure system have bulk compositions, mineral assemblages, colloform and bacteroidal textures, and oxygen isotope characteristics consistent with low-temperature (< 250 C ) deposition from less robust vents. Field relations and [sup 210]Pb ages (> 100 years) indicate that the Type 4 chimneys formed prior to the sheet flow eruption. The sulfide mounds and Type 1 and Type 2 chimneys at the Monolith and Fountain vents, however, are an expression of the same magmatic event that caused the sheet flow eruption and megaplume events.
OSTI ID:
5067396
Report Number(s):
CONF-9305259--
Conference Information:
Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 25:5
Country of Publication:
United States
Language:
English

Similar Records

Geology of the northern Cleft segment, Juan de Fuca Ridge: Recent lava flows, sea-floor spreading, and the formation of megaplumes
Journal Article · Thu Aug 01 00:00:00 EDT 1991 · Geology; (United States) · OSTI ID:5877503
Southern Juan De Fuca Ridge and Escanaba Trough, Gorda Ridge: Comparison of hydrothermal deposits in sediment-free and sediment-covered ridge settings
Conference · Fri Jun 01 00:00:00 EDT 1990 · AAPG Bulletin (American Association of Petroleum Geologists); (USA) · OSTI ID:6317651
Geology, mineralogy, and chemistry of sediment-hosted clastic massive sulfides in shallow cores, Middle Valley, northern Juan de Fuca Ridge
Journal Article · Tue Nov 30 23:00:00 EST 1993 · Economic Geology (plus the Bulletin of the Society of Economic Geologists); (United States) · OSTI ID:7049377

Related Subjects

15 GEOTHERMAL ENERGY
152002* -- Geothermal Data &amp; Theory-- Properties of Minerals &amp; Rocks
58 GEOSCIENCES
580000 -- Geosciences
AGE ESTIMATION
CHEMISTRY
DEVELOPED COUNTRIES
ENERGY SYSTEMS
FUMAROLES
GEOCHEMISTRY
GEOLOGIC DEPOSITS
GEOLOGIC FISSURES
GEOLOGIC STRUCTURES
GEOTHERMAL SYSTEMS
HYDROTHERMAL SYNTHESIS
HYDROTHERMAL SYSTEMS
ISOTOPE DATING
MINERALS
NORTH AMERICA
OREGON
PACIFIC OCEAN
SEAS
SULFIDE MINERALS
SURFACE WATERS
SYNTHESIS
USA
WASHINGTON