Sulfide geochronology along the Endeavour Segment of the Juan de Fuca Ridge
Jamieson, John W.
Hannington, Mark D.
Clague, David A.
Kelley, Deborah S.
Delaney, John R.
Holden, James F.
Tivey, Margaret K.
Kimpe, Linda E.
MetadataShow full item record
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 hydrothermal venting at the site over the past 6000 years. This dating method is effective for samples ranging in age from ∼200 to 20,000 years old and effectively bridges an age gap between shorter- and longer-lived U-series dating techniques for hydrothermal deposits. Results show that hydrothermal venting at the active High Rise, Sasquatch, and Main Endeavour fields began at least 850, 1450, and 2300 years ago, respectively. Barite ages of other inactive deposits on the axial valley floor are between ∼1200 and ∼2200 years old, indicating past widespread hydrothermal venting outside of the currently active vent fields. Samples from the half-graben on the eastern slope of the axial valley range in age from ∼1700 to ∼2925 years, and a single sample from outside the axial valley, near the westernmost valley fault scarp is ∼5850 ± 205 years old. The spatial relationship between hydrothermal venting and normal faulting suggests a temporal relationship, with progressive younging of sulfide deposits from the edges of the axial valley toward the center of the rift. These relationships are consistent with the inward migration of normal faulting toward the center of the valley over time and a minimum age of onset of hydrothermal activity in this region of 5850 years.
Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013); 2084–2099, doi:10.1002/ggge.20133.
Showing items related by title, author, creator and subject.
A preliminary 1-D model investigation of tidal variations of temperature and chlorinity at the Grotto mound, Endeavour Segment, Juan de Fuca Ridge Xu, Guangyu; Larson, Benjamin I.; Bemis, Karen G.; Lilley, Marvin D. (John Wiley & Sons, 2017-01-18)Tidal oscillations of venting temperature and chlorinity have been observed in the long-term time series data recorded by the Benthic and Resistivity Sensors (BARS) at the Grotto mound on the Juan de Fuca Ridge. In this ...
Seismic structure of the Endeavour Segment, Juan de Fuca Ridge : correlations with seismicity and hydrothermal activity Van Ark, Emily M.; Detrick, Robert S.; Canales, J. Pablo; Carbotte, Suzanne M.; Harding, Alistair J.; Kent, Graham M.; Nedimovic, Mladen R.; Wilcock, William S. D.; Diebold, John B.; Babcock, Jeffrey M. (American Geophysical Union, 2007-02-03)Multichannel seismic reflection data collected in July 2002 at the Endeavour Segment, Juan de Fuca Ridge, show a midcrustal reflector underlying all of the known high-temperature hydrothermal vent fields in this area. On ...
Recent seismic studies at the East Pacific Rise 8°20'–10°10'N and Endeavour Segment : insights into mid-ocean ridge hydrothermal and magmatic processes Carbotte, Suzanne M.; Canales, J. Pablo; Nedimovic, Mladen R.; Carton, Helene; Mutter, John C. (The Oceanography Society, 2012-03)As part of the suite of multidisciplinary investigations undertaken by the Ridge 2000 Program, new multichannel seismic studies of crustal structure were conducted at the East Pacific Rise (EPR) 8°20'–10°10'N and Endeavour ...