21 research outputs found
Rasprostraneniye i osobennosti zaleganiya subakvak'noy kriolitozons v rayone banok Semenovskaya i Vasil'evskaya (morye Laptevykh) po dannym seysmoakusticheskogo profilirovaniya (Distribution and peculiarity of bedding of the sub-sea permafrost near Semenovskoe and Vasilievsoe shoals (Laptev Sea) revealed by high-resolution seismic profiling, in Russian)
Ground-truthing 11- to 12-kHz side-scan sonar imagery in the Norwegia-Greenland Sea: Part I: Pockmarks on the Vestnesa Ridge and Storegga slide margin
The 230Th/U dating of sulfide ores in the ocean: Methodical possibilities, measurement results, and perspectives of application
Chetvertichnye otlozheniya, podzemnye Äľdy i Beregov Zapadnogo Taymyra (Quaternary deposits, ice complex and coastal dynamics of Western Tayimyr, in Russian)
Hydrothermal activity on the ultra-slow spreading southern Knipovich Ridge
We report first evidence for hydrothermal activity from the southern Knipovich Ridge, an ultra-slow spreading ridge segment in the Norwegian-Greenland Sea. Evidence comes from optical backscatter anomalies collected during a systematic side-scan sonar survey of the ridge axis, augmented by the identification of biogeochemical tracers in the overlying water column that are diagnostic of hydrothermal plume discharge (Mn, CH4, ATP). Analysis of coregistered geologic and oceanographic data reveals that the signals we have identified are consistent with a single high-temperature hydrothermal source, located distant from any of the axial volcanic centers that define second-order segmentation along this oblique ridge system. Rather, our data indicate a hydrothermal source associated with highly tectonized seafloor that may be indicative of serpentinizing ultramafic outcrops. Consistent with this hypothesis, the hydrothermal plume signals we have detected exhibit a high methane to manganese ratio of 2–3:1. This is higher than that typical of volcanically hosted vent sites and provides further evidence that the source of the plume signals reported here is most probably a high-temperature hydrothermal field that experiences some ultramafic influence (compare to Rainbow and Logachev sites, Mid-Atlantic Ridge). While such sites have previously been invoked to be common on the SW Indian Ridge, this may be the first such site to be located along the Arctic ultra-slow spreading ridge system