Seismic tremor at the 9°50′N East Pacific Rise eruption site

Seismic heterogeneity in the upper crust eruption site on the East Pacific Rise , 9 ø 50 ' N near the 1991

We report the results of a small-aperture uppercrustal tomography experiment conducted on the East Pacific Rise near 9ø50'N, the site of a volcanic eruption in 1991. The experiment geometry comprised 3 ocean bottom seismometers and 491 airgun shots fired in a 16 x 16 km 2 area. Twoand three-dimensional inversions indicate that the average upper crustal velocities, both on and off axis, increase...

Subsurface structure of a submarine hydrothermal system in ocean crust formed at the East Pacific Rise, ODP/IODP Site 1256

[1] ODP/IODP Hole 1256D penetrates an in situ section of ocean crust formed at the East Pacific Rise, through lavas and sheeted dikes and ∼100 m into plutonic rocks. We use mineralogy, oxygen isotopes, and fluid inclusions to understand hydrothermal processes. The lavas are slightly altered at low temperatures (<150°C) to phyllosilicates and iron oxyhydroxides, with a stepwise increase in grade...

Persistent effects of disturbance on larval patterns in the plankton after an eruption on the East Pacific Rise

To predict how benthic communities will respond to disturbance, it is necessary to understand how disturbance affects the planktonic larval supply available to recolonize the area. Deep-sea hydrothermal vent fauna along the East Pacific Rise (EPR) experience frequent local extinctions due to tectonic and magmatic events, but the effects on regional larval abundance and diversity are unknown. We...

Whole mantle shear structure beneath the East Pacific Rise

[1] We model broadband seismograms containing triplicated S, S, and S along with ScS to produce a pure path one-dimensional model extending from the crust to the core-mantle boundary beneath the East Pacific Rise. We simultaneously model all body wave shapes and amplitudes, thereby eliminating depth-velocity ambiguities. The data consist of western North American broadband recordings of East Pa...

Electrical structure beneath the northern MELT line on the East Pacific Rise at 15°45'S