The deep ocean, covering a vast expanse of the globe, relies almost exclusively on a food supply originating from primary production in surface waters. With well-documented warming of oceanic surface waters and conflicting reports of increasing and decreasing primary production trends, questions persist about how such changes impact deep ocean communities. A 24-y time-series study of sinking pa...

The Canary Island Seamount Province forms a scattered hotspot track on the Atlantic ocean floor ~1300 km long and ~350 km wide, perpendicular to lithospheric fractures, and parallel to the NW African continental margin. New (40)Ar/(39)Ar datings show that seamount ages vary from 133 Ma to 0.2 Ma in the central archipelago, and from 142 Ma to 91 Ma in the southwest. Combining (40)Ar/(39)Ar ages ...

The historically productive copper-bearing Besshi-type sulphide deposits in the Japanese accretionary complex were formed as volcanogenic massive sulphide deposits on the deep-sea floor of the Panthalassa Ocean. Here we report that eleven typical Besshi-type deposits yielded Re-Os isochron ages around 150 Ma (148.4 ± 1.4 Ma from the composite isochron) in Late Jurassic time. This date coincides...

During the past decades, Ocean Bottom Seismometers (OBS) have played a key role in permanent seismic activity monitoring at sea as well as allowing a better understating of the earth interior. Data collected by the instrument can provide information on the ocean bottom sub-layers down to a depth of 40 km beneath the ocean floor. The accuracy of the results directly depends on the time drift of ...

The recent speculation that the magnetic anomalies observed over oceanic ridges might be explained in terms of ocean-floor spreading and periodic reversals of the earth's magnetic field may now be reexamined in the light of suggested reversals during the past 4 million years and the newly described Juan de Fuca Ridge.

Deep-sea hydrothermal vents and cold seeps are submarine springs where nutrient-rich fluids emanate from the sea floor. Vent and seep ecosystems occur in a variety of geological settings throughout the global ocean and support food webs based on chemoautotrophic primary production. Most vent and seep invertebrates arrive at suitable habitats as larvae dispersed by deep-ocean currents. The recen...

This report summarizes written and oral contributions from many interested scientists, including 46 participants (Appendix 1) at a workshop executive summary 1 mapping the ocean floor 3 the need for bathymetry from space 3 sensing bathymetry from space 4 new science 6 ocean circulation, mixing, and climate 6 beyond plate tectonics 10 forecasting tsunamis 14 other applications of improved bathym...

A procedure for automatic mosaic construction over long image sequences is presented. This mosaic is used by an underwater vehicle to estimate its motion with respect to the ocean floor. The system exploits texture cues to solve the correspondence problem. The dynamic selection of a reference image extracted from the mosaic improves motion estimation, bounding accumulated error. Experiments wit...

The ocean floor is home to a wealth of species, some of which—such as this bamboo coral (Isidella tentaculum)—have only recently been discovered. Proponents of seabed mining claim it causes less ecological damage than terrestrial extraction. But some researchers are concerned that seabed mining could overwhelm deep-sea ecosystems, adding to concerns about the health of the oceans.