This page contains data associated with:

Saffer, D., Silver, E., Fisher, A., Tobin, H., Moran, K., 2000. Inferred pore pressures at the Costa Rica subduction zone: implications for dewatering processes, Earth Planet. Sci. Lett., 177 (3-4): 193-207.

There are three tables on this page:

Table 1: Sample Specification. Lists all samples collected during ODP Leg 170 for consolidation and permeability measurements (Saffer et al., 2000) and for Vp and Vs measurements. Explanation of column headings is given at the bottom of the data table.

Table 2: Summary of Consolidation Results. Lists the results of consolidation tests for each sample tested (and reported in Saffer et al., 2000). The results in the table include calculated overburden stress, maximum past burial stress, overconsolidation ratio, and characteristics of consolidation and rebound behavior. Explanation of column headings is given at the bottom of the data table.

Table 3: Summary of Permeability Results. Lists permeability measured at each of several void ratios for our samples. Each permeability value listed here was determined from measured of pressure differences across the sample at several (4-7) constant flow rates. Explanation of column headings is given at the bottom of the data table.

Table 1: Sample Specifications

Table 1 lists all samples collected during ODP Leg 170 for consolidation and permeability measurements (Saffer et al., 2000) and for Vp and Vs measurements (Tobin et al., 1999). Explanation of column headings is given at the bottom of the data table.

Sample IDa	Sectionb	Intervalc	Depth
		(cm)	(mbsf)
1039B-5H	2	135 - 150	33.35
1039B-6H	2	135 - 150	42.85
1039B-10H	2	135 - 150	80.85
1039B-11H	2	135 - 150	90.35
1039B-15X	8	15 - 30	132.27
1039B-16X	8	0 - 15	141.54
1039B-16X	8	0 - 15	141.54
1039B-21X	6	135 - 150	189.05
1039B-25X	5	0 - 15	224.7
1039B-26X	6	135 - 150	237.25
1039B-29X	6	135 - 150	266.25
1039B-30X	4	135 - 150	272.95
1039B-34X	4	135 - 150	311.45
1039B-34X	7	31 - 46	314.91
1039B-35X	7	14 - 29	324.34
1039B-39X	6	135 - 150	362.45
1039B-40X	7	29 - 43	372.49
1040B-9X	7	0 - 15	72.74
1040B-11X	7		93.1
1040B-20X	7	19 - 36	170.59
1040C-5R	2	80 - 95	199.9
1040C-10R	5	120 - 135	253
1040C-15R	5	135 - 150	301.45
1040C-17R	3	75 - 82	317.05
1040C-18R	1	121 - 136	324.21
1040C-19R	4	43 - 58	337.53
1040C-20R	6	77 - 92	350.47
1040C-21R	5	99 - 114	358.79
1040C-22R	6	135 - 150	370.25
1040C-23R	3	38 - 53	374.38
1040C-25R	2	20 - 35	391.9
1040C-27R	2	40 - 55	411.3
1040C-29R	1	135 - 150	429.95
1040C-30R	4	0 - 15	442.7
1040C-34R	1	135 - 150	478.05
1040C-38R	2	135 - 150	518.15
1040C-40R	2	0 - 15	536
1040C-42R	3	135 - 150	558.05
1040C-46R	4	135 - 150	598.15
1040C-50R	2	135 - 150	633.45
1040C-52R	2	16 - 31	651.66
1041A-10X	6	25 - 40	76.07
1041B-4R	6	20 - 35	190.61
1041B-18R	3	39 - 53	320.94
1043A-10X	2	82 - 97	83.02
1043A-12X	8	14 - 29	109.55
1043A-14X	5	84 - 99	126.04
1043A-15X	2	15 - 23	130.01
1043A-16X	5	0-15	143.92
1043A-17X	1	87-102	148.77
1043A-18X	2	0-15	159
1043A-19H	1	135-150	168.45
1043A-19H	5	135-150	174.15
1043A-21X	2	135-150	188.85
1043A-24X	5	135-150	222.15
1043A-28X	5	100-115	260.3

Legend for Table 1:

a: Sample ID includes ODP site (hole) number, and the type of core barrel used: H=hydraulic piston core, X=extended core barrel, R=rotary core barrel.

b: already on site

c: already on site

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Table 2: Summary of Consolidation Results

Table 2 lists the results of consolidation tests for each sample tested (and reported in Saffer et al., 2000). The results in the table include calculated overburden stress, maximum past burial stress, overconsolidation ratio, and characteristics of consolidation and rebound behavior. Explanation of column headings is given at the bottom of the data table. To access detailed data from consolidation tests on each sample, click on the sample ID numbers in Table 2. For additional information about methods used to process consolidation data, to estimate minimum and maximum preconsolidation stresses (as discussed in Saffer et al., 2000), or for any other questions, please e-mail Demian Saffer.

sample IDa	depth	OBb	Po' c	Pc' d	OCR e	U f	unit g	Svc h	Ivc i	Src j	Irc k
	(mbsf)	(kPa)	(kPa)	(kPa)		(kPa)
1039-10H	80.85	1110	290	290	0.99	0	1B	-1.62	7.41	-0.03	2.61
1039-16X	141.54	1930	510	1050	2.04	-530	2B	-3.13	12.99	-0.18	2.76
1039-21X	189.05	2590	690	640	0.94	40	3B	-0.37	2.75	-0.03	1.55
1039-26X	237.25	3320	940			940	3B
1039-29X	266.25	3760	1090			1090	3B
1039-34X	314.91	4480	1320			1320	3C
1039-39X	362.45	5190	1550			1550	3C
1040C-27R	411.3	7340	3210	1940	0.60	1270	1B	-0.50	2.92	-0.04	1.20
1040C-30R	442.7	7850	3410	1610	0.47	1800	2A	-0.58	3.34	-0.09	1.49
1040C-34R	478.05	8420	3620			3620	2B
1040C-38R	518.15	9050	3850	1370	0.36	2480	3B	-0.46	2.70	-0.03	1.08
1040C-42R	558.05	9720	4110	1650	0.40	2460	3B	-0.39	2.60	-0.04	1.29
1040C-46R	598.15	10340	4330	1690	0.39	2640	3C	-0.42	2.81	-0.04	1.37
1040C-46R	598.15	10340	4330	2320	0.54	2010	3C	-0.42	2.81	-0.04	1.37
1040C-50R	633.45	10920	4560			4560	3C
1040C-52R	651.66	11200	4670	1570	0.34	3090	3C	-0.22	1.72	-0.02	0.95

Legend for Table 2:

a: Sample ID includes ODP site (hole) number, and the type of core barrel used: H=hydraulic piston core, X=extended core barrel, R=rotary core barrel.

b: OB is overburden stress, calculated from LWD density data by integrating the weight of material overlying the sample.

c: Po' is predicted effective stress for sample, assuming hydrostatic pore pressure. This is calculated by: Po'=OB-(rwater*g*z), where g is gravitational acceleration and z is depth.

d: Pc' is estimated pre-consolidation stress, determined using the Casagrande construction (see Holtz & Kovacs [1981] for a detailed description of this method).

e: OCR is overconsolidation ratio, calculated by OCR=(Pc'/Po'). A value of unity corresponds to normally consolidated sediments.

f: U is excess pore pressure, calculated by U=(Po'-Pc'). A value of zero corresponds to normally consolidated sediments.

g: Lithologic Unit as described in ODP Leg 170 Initial Reports Volume. Units U1A and B consist of dark olive green diatomaceous ooze with ash layers. Unit U2 is distinguished by a sharp decrease in biogenic sediment, and is a dark olive-green silty clay interbedded with light olive-green calcareous clay; ash layers are common throughout Unit U2. Unit U3 records a dramatic increase in biogenic sedimentation, changing to calcareous and siliceous oozes; ash layers are sparse.

h: Svc is the slope of the virgin consolidation curve, determined using void ratios calculated from dry weight at end of consolidation tests. This slope defines the change in void ratio per log unit axial stress change.

i: Ivc is the intercept of the virgin consolidation curve at zero effective axial stress.

j: Src is the slope of the rebound curve determined during unloading of samples. This slope defines the change in void ratio per log unit axial stress change.

k: Irc is the intercept of the rebound curve at zero effective axial stress, for rebound from the maximum effective stress in each test.

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Table 3: Summary of Permeability Measurements

Table 3 lists permeability measured at each of several void ratios for our samples. Each permeability value listed here was determined from measured of pressure differences across the sample at several (4-7) constant flow rates. Explanation of column headings is given at the bottom of the data table.

Sample IDa	eb	log kc
		(m2)
1039B-10H-2	3.02	-15.9
1039B-10H-2	2.94	-16.0
1039B-10H-2	2.13	-16.4
1039B-10H-2	1.62	-16.4
1039B-16X-8	4.00	-14.8
1039B-16X-8	3.66	-15.5
1039B-16X-8	3.10	-16.4
1039B-16X-8	2.12	-17.1
1039B-16X-8	2.07	-17.6
1039B-26X-6	1.63	-14.2
1039B-26X-6	1.58	-14.8
1039B-26X-6	1.45	-15.0
1039B-26X-6	1.36	-15.3
1039B-26X-6	1.26	-15.2
1039B-26X-6	1.13	-15.5
1040C-30R-4	2.55	-16.8
1040C-30R-4	2.26	-16.9
1040C-30R-4	3.45	-15.8
1040C-30R-4	3.70	-15.1

Legend for Table 3:

a: Sample ID includes ODP site (hole) number, and the type of core barrel used: H=hydraulic piston core, X=extended core barrel, R=rotary core barrel.

b: e = sample void ratio during permeability measurement.

c: log k = log of permeability (m²).

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