Anhydrite precipitation and the extent of hydrothermal recharge zones at ocean ridge crests

Anhydrite precipitation and the extent of hydrothermal recharge zones at ocean ridge crests

[1] We develop mathematical models to investigate anhydrite precipitation in hydrothermal recharge zones at ocean ridge axes. We first consider constant flow during hydrothermal recharge to estimate the depth, the depth interval over which anhydrite precipitation would occur, and the initial rate of porosity reduction. We find that the smaller the downward mass flux, the shallower and more broa...

Analyses of the Velebit Mountain Ridge Crests

Generally the ridge crests spread in the dinaridic direction that is NW-SE what is mainly the characteristic of the older tectonic phase. The turn point in morphogenesis of the External Dinarides and thus of the Velebit Mt. occurs with the change in the shift of the Adriatic microplate toward N and NNW what is reflected on the orientation and morphology of the ridge crests as well as on the oth...

Fine-scale segmentation of volcanic/hydrothermal systems along fast-spreading ridge crests

Fine-scale (3rd and 4th order) segments of the mid-ocean ridge (MOR) are morphologically defined units of crustal accretion with enigmatic origins. At fast-spreading centers, 3rd order segments are bounded by discontinuities in the structure of the axial high. Most 3rd order segments are 20F10 km long, and terminate at ridge axis discontinuities (RADs) exhibiting 0.2–3 km lateral offsets and/or...

High-Resolution 3D Simulations of Mid-ocean Ridge Hydrothermal Systems

Rapid hydrothermal cooling above the axial melt lens at fast-spreading mid-ocean ridge

Axial melt lenses sandwiched between the lower oceanic crust and the sheeted dike sequences at fast-spreading mid-ocean ridges are assumed to be the major magma source of oceanic crust accretion. According to the widely discussed "gabbro glacier" model, the formation of the lower oceanic crust requires efficient cooling of the axial melt lens, leading to partial crystallization and crystal-melt...