Sulfide geochronology along the Northern Equatorial Mid-Atlantic Ridge

Tectonic structure, evolution, and the nature of oceanic core complexes and their detachment fault zones (13°20′N and 13°30′N, Mid Atlantic Ridge)

“…Early surveys carried out during Russian cruises located and defined several extinct hydrothermal fields throughout the 13°30′N detachment using a deep‐towed self‐potential system, in addition to TV‐camera surveys and sampling [ Bortnikov et al ., ; Cherkashev et al ., ; Cherkashov et al ., ; Pertsev et al ., ]. These data and results clearly demonstrate that hydrothermal activity has been present in space and time throughout the exposed fault surface, from its termination near the ridge axis to the limit of the corrugated surface to the west.…”

“…As at the 13°20′N OCC, the corrugated surface is covered by sediment and rubble, with hydrothermal deposits limited to the active Irinovskoe hydrothermal field (see below). In contrast, the 13°30′N corrugated surface shows sulfide rubble and mounds across much of its surface, corresponding to the hydrothermal fields identified in prior studies [ Cherkashov et al ., ; Pertsev et al ., ]. The fault scarps also reveal hydrothermal deposits resulting from fluid percolation both through the detachment fault zone and the overlying sediment and rubble (Figure C).…”

Exploring the Ecology of Deep-Sea Hydrothermal Vents in a Metacommunity Framework

“…In general, at spreading ridges the shortest-lived vent fields occur at fastspreading ridges, where they are under magmatic control, and the longest-lived (i.e., "thousands of years"; German et al, 2016) at slow-spreading systems controlled by tectonics. The age of a vent (time since initiation of hydrothermal activity) differs from longevity (duration of most recent hydrothermal activity), since hydrothermal activity may wax and wane over time (Cherkashov et al, 2017). Age tends to be inversely related to spreading rate (Jamieson et al, 2013), ranging from ∼100 years at 13 • N vent field on the fast-spreading EPR (Lalou et al, 1985) to ∼20,000 years at the TAG active field on the slow-spreading MAR (Cherkashov et al, 2017), but less is known about longevity.…”

“…The age of a vent (time since initiation of hydrothermal activity) differs from longevity (duration of most recent hydrothermal activity), since hydrothermal activity may wax and wane over time (Cherkashov et al, 2017). Age tends to be inversely related to spreading rate (Jamieson et al, 2013), ranging from ∼100 years at 13 • N vent field on the fast-spreading EPR (Lalou et al, 1985) to ∼20,000 years at the TAG active field on the slow-spreading MAR (Cherkashov et al, 2017), but less is known about longevity. Hydrothermal systems at volcanic arcs may be active for several thousands of years (e.g., Kermadec arc; de Ronde et al, 2007), whereas others may have decadal spans of activity that are more intimately related to volcanic cycles (Embley et al, 2014).…”

“…One is that the high disturbance rates at these eastern Pacific sites likely result in species assemblages at individual fields that do not reach equilibrium. In contrast, sites of particular interest for exploitation include large sulfide deposits that may have been active for thousands of years (Tao et al, 2014;German et al, 2016;Cherkashov et al, 2017), thus accumulating species diversities that are at or near equilibrium. Additionally, the close proximity of source communities in the studies on eastern and northeastern Pacific explain, in part, the relative rapid recovery.…”