4. Assuming that the P velocity in the ocean is 1.5 km/s, estimate the minimum and...

 

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4. Assuming that the P velocity in the ocean is 1.5 km/s, estimate the minimum and maximum water depths shown in Figure 1.8. If the crustal P velocity is 5 km/s, what is the depth to the top of the magma chamber from the seafloor? Hint: Remember that the times are for surface-to-reflector-to-surface paths (i.e., two legs between the surface and the reflector). jn tho chear modulus D 3.0 East WEst 3.5 Laver 24 4.0 AMC 4.5 Figure 1.8 An image of the axial magma chamber (AMC) beneath the East Pacific Rise near 14°15'S abtained through migration processing of reflection seismic data (from Kent et al., 1994). The profile is about 7 km across, with the vertical axis representing the two-way travel time of compressional waves between the surface of the ocean and the reflection point. The sea floor is the reflector at about 3.5 s in the middle of the plot, while the magma chamber appears at about 4.0 s and is roughly 750 m wide. Shallow axial magma chambers are commonly seen beneath fast-spreading oceanic ridges, such as those in the eastern Pacific, but not beneath slow-spreading ridges, such as the Mid-Atlantic Ridge. Time (s) 4. Assuming that the P velocity in the ocean is 1.5 km/s, estimate the minimum and maximum water depths shown in Figure 1.8. If the crustal P velocity is 5 km/s, what is the depth to the top of the magma chamber from the seafloor? Hint: Remember that the times are for surface-to-reflector-to-surface paths (i.e., two legs between the surface and the reflector). jn tho chear modulus D 3.0 East WEst 3.5 Laver 24 4.0 AMC 4.5 Figure 1.8 An image of the axial magma chamber (AMC) beneath the East Pacific Rise near 14°15'S abtained through migration processing of reflection seismic data (from Kent et al., 1994). The profile is about 7 km across, with the vertical axis representing the two-way travel time of compressional waves between the surface of the ocean and the reflection point. The sea floor is the reflector at about 3.5 s in the middle of the plot, while the magma chamber appears at about 4.0 s and is roughly 750 m wide. Shallow axial magma chambers are commonly seen beneath fast-spreading oceanic ridges, such as those in the eastern Pacific, but not beneath slow-spreading ridges, such as the Mid-Atlantic Ridge. Time (s)