Anselmetti, F.S., Isern, A.R., Blum, P., and Betzler, C. (Eds.) Proceedings of the Ocean Drilling Program, Scientific Results Volume 194 7. DATA REPORT: COMPRESSIBILITY , PERMEABILITY , AND GRAIN SIZE OF SHALLOW SEDIMENTS, SITES 1194 AND 1198 1 Brandon Dugan, 2, 3 Chris Marone, 2 Tiancong Hong, 2 and Misty Migyanka 2 ABSTRACT Uniaxial strain consolidation experiments were conducted to deter- mine elastic and plastic properties and to estimate the permeability of sediments from 0 to 200 meters below seafloor at Ocean Drilling Pro- gram Sites 1194 and 1198. Plastic deformation is described by compres- sion indices, which range from 0.19 to 0.37. Expansion indices, the elastic deformation measured during unload/reload cycles on samples, vary from 0.02 to 0.029. Consolidation experiments provide lower bounds on permeability between 5.4 10 –16 m 2 and 1.9 10 –18 m 2 , de- pending on the consolidation state of the sample. INTRODUCTION Carbonate and siliciclastic sediments of the Marion Plateau, offshore Australia, were investigated during Ocean Drilling Program (ODP) Leg 194 (Fig. F1). In this study, we focus on the physical properties of Pliocene to late Miocene sediments at Sites 1194 (0–100 meters below sea floor [mbsf]) and 1198 (100–200 mbsf) (Table T1). Site 1194 is lo- cated east of the Northern Marion Platform in 373.9 m of water (Fig. F1B). It was drilled to 427.1 mbsf and penetrated sediment Megase- quences D and B (Isern, Anselmetti, Blum, et al., 2002). From 0 to 100 mbsf, Site 1194 is dominated by mudstone and wackestone. Site 1198 is 16° S 146°E 150° 154° 24° 20° 400 0 km Australia 1000 m 1000 m 2000 m 4000 m 3000 m 20° S 21° 152°E 153° 0 100 km Site 1194 Site 1198 200 m 600 m Study region Study region B A F1. Location and bathymetry of study region, p. 7. T1. Samples used in consolidation experiments, p. 16. 1 Dugan, B., Marone, C., Hong, T., and Migyanka, M., 2004. Data report: Compressibility, permeability, and grain size of shallow sediments, Sites 1194 and 1198. In Anselmetti, F.S., Isern, A.R., Blum, P., and Betzler, C. (Eds.), Proc. ODP, Sci. Results, 194, 1–28 [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/ publications/194_SR/VOLUME/ CHAPTERS/003.PDF>. [Cited YYYY- MM-DD] 2 Department of Geosciences, The Pennsylvania State University, 305 Deike Building, University Park PA 16802, USA. 3 Present address: U.S. Geological Survey, 384 Woods Hole Road, Woods Hole MA 02543, USA. [email protected]Initial receipt: 29 June 2003 Acceptance: 3 March 2004 Web publication: 13 August 2004 Ms 194SR-003
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Anselmetti, F.S., Isern, A.R., Blum, P., and Betzler, C. (Eds.)Proceedings of the Ocean Drilling Program, Scientific Results Volume 194
7. DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE OF SHALLOW SEDIMENTS, SITES 1194 AND 11981
Brandon Dugan,2, 3 Chris Marone,2 Tiancong Hong,2 and Misty Migyanka2
ABSTRACT
Uniaxial strain consolidation experiments were conducted to deter-mine elastic and plastic properties and to estimate the permeability ofsediments from 0 to 200 meters below seafloor at Ocean Drilling Pro-gram Sites 1194 and 1198. Plastic deformation is described by compres-sion indices, which range from 0.19 to 0.37. Expansion indices, theelastic deformation measured during unload/reload cycles on samples,vary from 0.02 to 0.029. Consolidation experiments provide lowerbounds on permeability between 5.4 � 10–16 m2 and 1.9 � 10–18 m2, de-pending on the consolidation state of the sample.
INTRODUCTION
Carbonate and siliciclastic sediments of the Marion Plateau, offshoreAustralia, were investigated during Ocean Drilling Program (ODP) Leg194 (Fig. F1). In this study, we focus on the physical properties ofPliocene to late Miocene sediments at Sites 1194 (0–100 meters belowsea floor [mbsf]) and 1198 (100–200 mbsf) (Table T1). Site 1194 is lo-cated east of the Northern Marion Platform in 373.9 m of water (Fig.F1B). It was drilled to 427.1 mbsf and penetrated sediment Megase-quences D and B (Isern, Anselmetti, Blum, et al., 2002). From 0 to 100mbsf, Site 1194 is dominated by mudstone and wackestone. Site 1198 is
16°S
146°E 150° 154°
24°
20°
4000 km
Australia
1000 m
1000 m 2000
m
4000 m
3000
m
20°S
21°
152°E 153°
0 100km
Site1194
Site1198
200 m
600 m
Study region
Studyregion
BA
F1. Location and bathymetry of study region, p. 7.
T1. Samples used in consolidation experiments, p. 16.
1Dugan, B., Marone, C., Hong, T., and Migyanka, M., 2004. Data report: Compressibility, permeability, and grain size of shallow sediments, Sites 1194 and 1198. In Anselmetti, F.S., Isern, A.R., Blum, P., and Betzler, C. (Eds.), Proc. ODP, Sci. Results, 194, 1–28 [Online]. Available from World Wide Web: <http://www-odp.tamu.edu/publications/194_SR/VOLUME/CHAPTERS/003.PDF>. [Cited YYYY-MM-DD]2Department of Geosciences, The Pennsylvania State University, 305 Deike Building, University Park PA 16802, USA.3Present address: U.S. Geological Survey, 384 Woods Hole Road, Woods Hole MA 02543, USA. [email protected]
Initial receipt: 29 June 2003Acceptance: 3 March 2004Web publication: 13 August 2004Ms 194SR-003
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 2
located northwest of the Southern Marion Platform in 319.4 m of water(Fig. F1B). Drilling Site 1198 to 522 mbsf recovered sediments from Me-gasequences D, C, and B (Isern, Anselmetti, Blum, et al., 2002). Westudied Site 1198 from 100 to 200 mbsf, where the lithology is mud-stone to skeletal grainstone.
We measured the sample deformation that results from an appliedvertical effective stress under uniaxial strain conditions. This providesinsights into the void ratio (or porosity), density, and permeability ofthe sediments during burial and consolidation. These properties influ-ence heat and chemical transport in and around the Marion Plateauand affect the strength of the sediments.
MATERIALS AND METHODS
Whole-round core samples were sealed in the core liner during Leg194 to preserve the natural sample saturation. For each experiment, acore was removed from its liner and a vertically oriented, cylindricalsubsample was trimmed and inserted in the fixed-ring consolidationcell. Each vertically oriented subsample had a diameter of 47.9 mm andan initial height of 19 mm. The mass (m) and volume (V) of each sub-sample was measured to calculate bulk density (�b = m/V). All variablesare defined in the nomenclature table (Table T2). Porous endcaps at thetop and bottom of the cylindrical samples facilitated even drainagefrom the sample ends.
Initial sample porosity (�o) was calculated with equation 1 (Fig. F2;Table T1), assuming a water density (�w) of 1000 kg/m3, a grain density(�s) of 2600 kg/m3, and 100% water saturation:
�o = (�s – �b)/(�s–�w). (1)
The initial porosity calculations neglect salt in the pore fluid. Calcula-tions that account for salt mass in the system (Blum, 1997) result in lessthan 0.7% change in initial porosity.
Consolidation Experiments
Ten consolidation experiments were performed; five on samplesfrom Site 1194 and five on samples from Site 1198 (Table T1; Fig. F2).Each sample was placed in the load frame, where contact between thesample, porous disks, and ram were established manually. Vertical stresswas then computer-controlled throughout the consolidation experi-ment. Stress was increased at 0.1-MPa increments to ~0.5 MPa and thenby 0.5-MPa increments to ~4 MPa. The samples were then unloaded to1 MPa, reloaded to 4 MPa, and then loaded by 0.5-MPa stress incre-ments to 6 MPa. Experiments concluded with unloading at 1-MPa inter-vals. Each stress increment (increase or decrease) occurred at ~0.1 MPa/sand was followed by a stress hold to allow excess pressure dissipationand completion of primary consolidation. After the completion of pri-mary consolidation and onset of secondary compression, another stressincrement was applied. Stress holds for the completion of primary con-solidation were <15 min for these samples. Analysis of sample height asa function of time (log-time method) (Lambe and Whitman, 1979;Craig, 1992) was used to confirm the completion of primary consolida-tion, dissipation of excess pore pressure, and onset of secondary com-
T2. Nomenclature, p. 17.
Dep
th (
mbs
f)
0
20
40
60
80
100
120
140
160
180
20035 5040 45
Porosity, φ (%) Core, section
Hole 1198A
Hole 1194A
1194A-5H-3
1194A-8H-3
1194A-11H-3
1198A-15H-3
1198A-18H-3
1198A-21H-3
1198A-13H-3
F2. Initial porosity and depth of experimental samples, p. 8.
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 3
pression. Sample height was measured throughout the experiments andsample diameter was constant; this allowed sample volume and poros-ity to be calculated throughout the entire experiment with equation 2(nomenclature is defined in Table T2):
The sample void ratio (e = �/[1–�]) and stress at the end of each stresshold are used to calculate the compression (cc) and expansion (ce) indi-ces of the samples. The compression index in equation 3 characterizesplastic deformation along the linear portion of the e-log(�v�� plot, whichis interpreted to represent primary (virgin) consolidation (e.g., Craig,1992):
cc = (e�v� – e�v�+��v�)/log[(�v�+��v�)/(�v�)]. (3)
The expansion index in equation 4 describes the elastic portion ofthe e-log(�v�� plot characterized by the linear unloading/reloading paths(e.g., Craig, 1992):
ce = (e�v� – e�v�+��v�)/log[(�v�+��v�)/(�v�)]. (4)
Sample deformation during stress holds provided estimates of the co-efficient of consolidation (cv) and of the permeability (k) of the samplesat multiple consolidation states during virgin deformation (Table T3).The log-time method was used to estimate cv for primary consolidation(see Lambe and Whitman, 1979; Craig, 1992), and k was calculated us-ing cv with equation 5:
k = cvmvµ, (5)
where
mv = the coefficient of volume compressibility (mv = [1/(1+eo)][–�e/��v�]) for a given effective vertical stress increment (��v�),
µ = the dynamic viscosity of water (we assume µ = 0.001 Pa·s),eo = the initial void ratio, and�e = the change in void ratio during the stress hold (Table T2).
Grain Size Analysis
A Malvern Master-Sizer Dynamic Laser Light Scattering/Light Diffrac-tion Particle Size Distribution Analyzer was used to determine grain sizeon seven samples from Sites 1194 and 1198. The particle size analyzercan measure particle sizes from 0.05 to 900 µm.
We evaluated the grain size distribution for each core section in thestudy (Table T3).
Dry sediment samples were mixed with deionized water to make asediment-water mixture. The mixture was placed in a sonicator andstirred to establish a uniform concentration of particles in the water.The mixture was then analyzed to evaluate the grain size distribution;d10, d50, and d90 are reported (d10 = the grain size at which 10% of sam-ple is finer, d50 = the grain size at which 50% of sample is finer, and d90
is the grain size at which 90% of sample is finer) (Tables T2, T3). Dupli-
T3. Consolidation and grain size results, p. 18.
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 4
cate and triplicate analyses were performed and standards were ana-lyzed to demonstrate reproducibility of the distributions.
RESULTS
Results from the experiment are included in Tables T4, T5, T6, T7,T8, T9, T10, T11, T12, and T13 and Figures F3, F4, F5, F6, F7, F8, andF9. Compression indices (cc) for the samples ranged from 0.19 to 0.37,and expansion indices were approximately 10% of the compression in-dices (0.02 < ce < 0.029) (Table T3). Sample 194-1194A-5H-3, 135–137cm, had the greatest decrease in void ratio during loading (Fig. F3). Thiswas the shallowest sample, and its entire deformation path was plasticdeformation. Samples 194-1194A-8H-3, 138–140 cm, and 194-1198A-21H-3, 140–142 cm, had the highest compression indices (Table T3) butexperienced plastic deformation for stresses exceeding ~1 MPa (Figs.F4B, F9); they had less total deformation than Sample 194-1194A-5H-3,135–137 cm, which had a lower compression index.
Estimated permeability (Table T3) was greatest (5.4 � 10–16 m2) forSample 194-1198A-15H-3, 135–137 cm, at an effective vertical stress of0.99 MPa. The same sample had the lowest estimated permeability (1.9� 10–18 m2) of all the experiments at an effective vertical stress of 5.3MPa. The consolidation experiments were performed without samplebackpressure; therefore, partial air saturation may have developed. Par-tial air saturation impedes water drainage; thus, the consolidation-based permeability could be lower than the absolute permeability ofthe sample with 100% water saturation. Moran et al. (1995) comparedconsolidation-estimated permeability to low-gradient permeabilitymeasurements and documented that consolidation-estimated permea-bility was equal to or lower than direct low-gradient measurements ofpermeability. With the possibility of partial air saturation and the con-solidation method of estimating permeability, our estimates are consid-ered a lower bound on permeability for these sediments.
Holes 1194A and 1198A have similar d10 and d50 that do not vary sig-nificantly with depth (Table T3). Exceptions to this are (1) increased d10
(1.3 µm) of Sample 194-1194A-11H-3, 135–137 cm, and (2) increasedd50 (54 µm) of Sample 194-1198A-13H-3, 139–141 cm (Table T3). Themajor grain size variation between the sites is d90; Hole 1194A has amaximum d90 = 89 µm, and d90 decreases with depth. In contrast, Hole1198A is dominated by d90 > 100 µm and shows no depth trend (TableT3).
ACKNOWLEDGMENTS
This research used samples and/or data provided by the Ocean Drill-ing Program (ODP). ODP is sponsored by the U.S. National ScienceFoundation (NSF) and participating countries under management ofJoint Oceanographic Institutions (JOI), Inc. This research was supportedby a JOI/U.S. Science Advisory Committee grant (Dugan). Reviews andcomments by P. Blum, D. Saffer, and E. Screaton strengthened themanuscript.
T4. Stress and porosity, Sample 194-1194A-5H-3, 135–137 cm, p. 19.
T5. Stress and porosity, Sample 194-1194A-8H-3, 135–137 cm, p. 20.
T6. Stress and porosity, Sample 194-1194A-8H-3, 138–140 cm, p. 21.
T7. Stress and porosity, Sample 194-1194A-8H-3, 142–144 cm, p. 22.
T8. Stress and porosity, Sample 194-1194A-11H-3, 135–137 cm, p. 23.
T9. Stress and porosity, Sample 194-1198-13H-3, 135–137 cm, p. 24.
T10. Stress and porosity, Sample 194-1198A-13H-3, 139–141 cm, p. 25.
T11. Stress and porosity, Sample 194-1198A-15H-3, 135–137 cm, p. 26.
T12. Stress and porosity, Sample 194-1198A-18H-3, 135–137 cm, p. 27.
T13. Stress and porosity, Sample 194-1198A-21H-3, 140–142 cm, p. 28.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
Por
osity
, φ (
%)
45
40
35
30
25
0.3
F3. Deformation behavior, Section 194-1194A-5H-3, p. 9.
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 5
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
A
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B
Effective vertical stress, σv' (MPa)
0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
C
F4. Deformation behavior, Section 194-1194A-8H-3, p. 10.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
F5. Deformation behavior, Section 194-1194A-11H-3, p. 11.
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
A
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B
F6. Deformation behavior, Section 194-1198A-13H-3, p. 12.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
F7. Deformation behavior, Section 194-1198A-15H-3, p. 13.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
F8. Deformation behavior, Section 194-1198A-18H-3, p. 14.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
F9. Deformation behavior, Section 194-1198A-21H-3, p. 15.
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 6
REFERENCES
Blum, P., 1997. Physical properties handbook: a guide to the shipboard measurementof physical properties of deep-sea cores. ODP Tech. Note, 26 [Online]. Availablefrom World Wide Web: <http://www-odp.tamu.edu/publications/tnotes/tn26/INDEX.HTM>. [Cited YYYY-MM-DD]
Craig, R.F., 1992. Soil Mechanics: London (Chapman and Hall).Isern, A.R., Anselmetti, F.S., Blum, P., et al., 2002. Proc. ODP, Init. Repts., 194 [Online].
Available from World Wide Web: <http://www-odp.tamu.edu/publications/194_IR/194ir.htm>. [Cited 2003-06-29]
Lambe, T.W., and Whitman, R.V., 1979. Soil Mechanics (SI ver.): New York (Wiley).Moran, K., Gray, W.G.D., and Jarrett, C.A., 1995. Permeability and stress history of
sediment from the Cascadia margin. In Carson, B., Westbrook, G.K., Musgrave,R.J., and Suess, E. (Eds.), Proc. ODP, Sci. Results, 146 (Pt. 1): College Station, TX(Ocean Drilling Program), 275–280.
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 7
Figure F1. A. Location and bathymetry of the study region (shaded box), offshore Australia. Contour inter-val = 1000 m. B. Bathymetry of the Marion Plateau study region documenting the location of Sites 1194and 1198 (solid circles). Contour interval = 200 m.
16°S
146°E 150° 154°
24°
20°
4000 km
Australia
1000 m
1000 m 2000
m
4000 m
3000
m
20°S
21°
152°E 153°
0 100km
Site1194
Site1198
200 m
600 m
Study region
Studyregion
BA
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 8
Figure F2. Initial porosity and depth of experimental samples from Holes 1194A and 1198A. Core and sec-tion for each sample are labeled.
Dep
th (
mbs
f)
0
20
40
60
80
100
120
140
160
180
20035 5040 45
Porosity, φ (%) Core, section
Hole 1198A
Hole 1194A
1194A-5H-3
1194A-8H-3
1194A-11H-3
1198A-15H-3
1198A-18H-3
1198A-21H-3
1198A-13H-3
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 9
Figure F3. Deformation behavior for Sample 194-1194A-5H-3, 135–137 cm. Void ratio is plotted on a linearscale on the left y-axis and equivalent porosity is plotted on the right y-axis. Gray arrows illustrate loading/unloading/reloading paths. Raw data are provided in Table T4, p. 19.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
Por
osity
, φ (
%)
45
40
35
30
25
0.3
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 10
Figure F4. Deformation behavior for (A) Sample 194-1194A-8H-3, 135–137 cm, (B) Sample 194-1194A-8H-3, 138–140 cm, and (C) Sample 194-1194A-8H-3, 142–144 cm. Void ratio is plotted on a linear scale on theleft y-axis and equivalent porosity is plotted on the right y-axis. Gray arrows illustrate loading/unloading/reloading paths. Raw data are provided in Tables T5, p. 20, T6, p. 21, and T7, p. 22.
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
A
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B
Effective vertical stress, σv' (MPa)
0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
C
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 11
Figure F5. Deformation behavior for Sample 194-1194A-11H-3, 135–137 cm. Void ratio is plotted on a lin-ear scale on the left y-axis and equivalent porosity is plotted on the right y-axis. Gray arrows illustrate load-ing/unloading/reloading paths. Raw data are provided in Table T8, p. 23.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 12
Figure F6. Deformation behavior for (A) Sample 194-1198A-13H-3, 135–137 cm, and (B) Sample 194-1198A-13H-3, 139–141 cm. Void ratio is plotted on a linear scale on the left y-axis and equivalent porosityis plotted on the right y-axis. Gray arrows illustrate loading/unloading/reloading paths. Raw data are pro-vided in Tables T9, p. 24, and T10, p. 25.
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
A
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 13
Figure F7. Deformation behavior for Sample 194-1198A-15H-3, 135–137 cm. Void ratio is plotted on a lin-ear scale on the left y-axis and equivalent porosity is plotted on the right y-axis. Gray arrows illustrate load-ing/unloading/reloading paths. Raw data are provided in Table T11, p. 26.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 14
Figure F8. Deformation behavior for Sample 194-1198A-18H-3, 135–137 cm. Void ratio is plotted on a lin-ear scale on the left y-axis and equivalent porosity is plotted on the right y-axis. Gray arrows illustrate load-ing/unloading/reloading paths. Raw data are provided in Table T12, p. 27.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 15
Figure F9. Deformation behavior for Sample 194-1198A-21H-3, 140–142 cm. Void ratio is plotted on a lin-ear scale on the left y-axis and equivalent porosity is plotted on the right y-axis. Gray arrows illustrate load-ing/unloading/reloading paths. Raw data are provided in Table T13, p. 28.
Effective vertical stress, σv' (MPa)0.01 0.1 1 10
Voi
d ra
tio, e
0.9
0.8
0.7
0.6
0.5
0.4
0.3
Por
osity
, φ (
%)
45
40
35
30
25
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 16
Table T1. Samples used in consolidation experi-ments.
Core, section, interval (cm) Age
Depth (mbsf)
Initial porosity (%)
194-1194A-5H-3, 135–137 Pliocene 37.55 42.68H-3, 135–137 late Miocene 66.05 41.28H-3, 138–140 late Miocene 66.08 44.88H-3, 142–144 late Miocene 66.12 43.411H-3, 135–137 late Miocene 94.55 37.7
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 17
Table T2. Nomenclature.
Note: L = length, T = time, M = mass.
Variable Definition Dimensions SI unit
cc Compression index Dimensionless —ce Expansion index Dimensionless —cv Coefficient of consolidation L2/T m2/sd10 Grain size at which 10% of sample is finer L µmd50 Grain size at which 50% of sample is finer L µmd90 Grain size at which 90% of sample is finer L µme Void ratio Dimensionless —eo Initial void ratio Dimensionless —�e Change in void ratio Dimensionless —k Permeability L2 m2
m Sample mass M kgmv Coefficient of volume compressibility LT2/M 1/PaV Sample volume L3 m3
B. DUGAN ET AL.DATA REPORT: COMPRESSIBILITY, PERMEABILITY, AND GRAIN SIZE 18
Table T3. Summary of consolidation and grain size results.
Note: cc = compression index, ce = expansion index. d10 = grain size at which 10% of sample isfiner, d50 = grain size at which 50% of sample is finer, d90 = grain size at which 90% of sam-ple is finer.