Table T18. Correlation of reflection traveltime with the lithostratigraphic column using measured P-wave velocities, Site 1179.
| Traveltime (s) | Depth (mbsf) |
Velocity (m/s) | Reflection strength |
Correlation | ||
|---|---|---|---|---|---|---|
|
Observed
|
Estimated
|
Corrected*
|
Interval
|
|||
| 0 | 0 | 1470 | Strong | Seafloor | ||
| 0.018 | 1579 | Weak | ? | |||
| 0.038 | 0.040 | 60 | 1486 | Weak | Small perturbation in PWL velocity at 60 mbsf | |
| 1622 | ||||||
| 0.075 | 0.080 | 120 | 1502 | Weak | Very slight increase in velocity at 120 mbsf | |
| 1400 | ||||||
| 0.100 | 0.105 | 155 | 1512 | Weak | Slight increase in density at 155 mbsf | |
| 2000 | ||||||
| 0.115 | 0.125 | 185 | 1520 | Weak | Increases in velocity and density at 185 mbsf | |
| 0.132 | 1027 | Weak | ? | |||
| 1530 | ||||||
| 0.152 | 0.149 | 223 | Weak | Unit I/Unit II: increase in density at 215-225 mbsf | ||
| 1540 | ||||||
| 2400 | ||||||
| 1546 | ||||||
| 0.162 | 0.165 | 247 | Weak | Unit II/Unit III: abrupt change in velocity and density at 245 mbsf | ||
| 1556 | ||||||
| 0.172 | Strong | ? | ||||
| 1566 | ||||||
| ? | 0.188 | 283 | Strong | Unit III/Unit IV: top of chert | ||
| 0.220 | Strong | ? | ||||
| 0.250 | 275 | Moderate | Unit IV/Unit V: top of basement | |||
Notes: * = Measured velocities have been corrected for in situ temperature at top and bottom of each lithostratigraphic unit: dV/dT = 3.2 m/s/°C. PWL = P-wave logger. Data from seismic profile line 2-1, Hakuho Maru, August 1996. ? = no correlation. This table is also available in ASCII format.