[PDF] Top 20 Seismic structure of the lithosphere and upper mantle beneath the ocean islands near mid-oceanic ridges

... azimuths. We visually picked the waveforms having clear P - waves in the vertical component for further analysis. First, the Z, N and E components are rotated into Z (vertical), R (radial), and T (transverse) system ... See full document

... below islands where 3-D effects are con- strained by ...Indian Ocean and Tristan da Cunha in the South Atlan- tic, to estimate and invert ...profile beneath Gan island exhibits no anomalous behavior ... See full document

... isotherm. Lithosphere thickness estimates based on heat flow studies ...rigid mantle roots under these ...the upper mantle results in a chemical boundary layer with a higher viscosity, while ... See full document

... velocity structure beneath the South Pacific superswell down to a depth of 200 km by analyzing fundamental Rayleigh wave records from permanent and temporary land-based and seafloor seismometers in the ... See full document

... to oceanic spreading. Yet the role that pre-existing lithospheric structure, melt, mantle flow, or active upwellings may play in this process is ...of seismic anisotropy are often used to ... See full document

... discontinuity structure with predicted depths of phase transitions and mineral reactions calculated with Perple_X (Connolly 2005) (see ...and mid ocean ridge basalt (MORB) compositions (Table ...bulk ... See full document

... of seismic anisotropy at oceanic spreading centres offer insights into mid-ocean ridge processes and the formation of new ...of seismic anisotropy beneath mid-ocean ... See full document

... apparently near-conductive val- ues in the upper crust ( ∼ 200 mW m −2 ) to much lower values (< 100 mW m −2 ) at depths greater than ∼ 700 m from the basement ... See full document

... After a detailed search for events that have suitable geometry for sampling the superdome edge and possible plume, we found four events (Figure 4.17) that could be analyzed as presented below. The record section in ... See full document

... zonal geologic terrains associated with the collision tec- tonics of the opening of the Japan Sea in the Middle Miocene and the migration of the PHS plate that oc- curred until 6 Ma (Takahashi and Saito 1997). Although ... See full document

... reconstructed mantle sections for pipe Mir, Internatsionalnaya pipes (Ashchepkov et ...The mantle section beneath the Internatsionalnaya pipe according to the P- Fe # garnet trend may be also fertile ... See full document

... a seismic survey consisting of MCS and wide-angle seismic measurements using dense ocean bot- tom seismograph (OBS) receivers to update the velocity model of the SB, which is a typical backarc ... See full document

... the mantle return flows. The thickness of the lithosphere in the south of the West Philippine Basin reached about 100 km, which is much thicker than the results of previous studies for this ... See full document

... Most discussions of the MORB source composition focus on something called the depleted MORB source or the depleted mantle. To deduce its composition the discussions usually focus on something called “normal MORB”. ... See full document

... the mid-latitude region de®ned as 1,000±200 mbar, 288±688 latitude, for each ...the mid-latitude ...the mid-latitude region and the surface ¯uxes of sensible heat, although the contribution of ... See full document

... Tethys lithosphere thrusts be- neath the Eurasia, and the slab detachment reached into the lower mantle (Hafkenscheid et ...the oceanic crust may decouple from the subducted slab under the con- ... See full document

... A second important outcome of our simulations is that the integrated strength of faults must include contributions from both the brittle and the ductile parts of the crust, at least for major faults. The significance of ... See full document

... One-dimensional reference models are employed almost in every seismological method aimed at imaging of Earth’s inte- rior (tomography, receiver functions, underside reflections). However, results of those methods can be ... See full document

... Identify at least two characteristics of seafloor rocks change in a consistent way as distance from mid ocean ridges increases..[r] ... See full document

... adakite relative to classical island arc rocks defined by [40], (Fig. 10). Figure 13 shows a spider diagram plot for representative samples from different domes normalized to primitive mantle composition [68]. All ... See full document