Initial Reports Volume 191
Chapter 4, Table 19. Correlations of reflection traveltime with the lithostratigraphic column, Site 1179.

Notes: * = Depths estimated using z = -3030 x ln(1 - 0.52t) (Carlson et al., 1986). ** = Velocity estimated from v(z) = 1590 exp(0.00033z) (Carlson et al., 1986). PWL = P-wave logger, GRA = gamma-ray attenuation, NGR = natural gamma ray. ? = no correlation. 

Seismic line 2-1					Seismic line 2-4				
One-way traveltime (s)	Depth* (mbsf)	Velocity calculated** (m/s)	Velocity Interval	One-way traveltime (s)	Depth* (mbsf)	Velocity calculated** (m/s)	Velocity Interval	Reflection strength	Correlation

0	0	1590		0	0	1590			
			1556			1556		 
0.018	28	1605		0.018	28	1605	Weak	?
			1600							
0.038	60	1622				1607	Weak	Small perturbation in PWL velocity at 60 mbsf
			1649	0.057	91	1639	Weak	Very slight change in GRA density
0.075	121	1655				1615	Weak	Very slight increase in velocity at 120 mbsf
			1651							
0.100	162	1677		0.100	162	1677	Weak	Slight increase in density at 155 mbsf
			1669			1669		
0.115	187	1691		0.115	187	1691	Weak	Increases in velocity and density at 185 mbsf
			1684			1687		
0.132	215	1707		0.138	226	1713	Weak	Unit I/Unit II at ~221-222 (221.5) m: increase in density at 215-225 mbsf
			1701			1706		
0.152	249	1726		0.155	255	1729		Strong	Unit II/Unit III at ~247 m: abrupt changes in velocity and density at 245 mbsf
			1716			1721		
0.162	267	1736		0.170	280	1744	Weak	Changes in PWL velocity, GRA density, and NGR at 260-270 mbsf
			1725			1733		
0.172	284	1746		0.180	298	1754	Strong	Unit III/Unit IV: top of chert at ~283 mbsf
			1755			1764		
0.220	368	1795		0.230	386	1806	Strong	Unit IV/Unit V:  top of basement at ~375 mbsf
			1795							
0.250	422	1828					Moderate	?