stratigraphic framework and heavy- mineral resource potential of the ...
STRATIGRAPHIC FRAMEWORK AND HEAVYMINERAL RESOURCE POTENTIAL OF THE INNER CONTINENTAL SHELF, CAPE FEAR AREA, NORTH CAROLINA: FIRST INTERIM PROGRESS REPORT
NORTH CAROLINA GEOLOGICAL SURVEY OPEN-FILE REPORT 91-3
DIVISION OF LAND RESOURCES DEPARTMENT OF ENVIRONMENT, HEALTH, AND NATURAL RESOURCES
STRATIGRAPHIC FRAMEWORK AND HEAVYMINERAL RESOURCE POTENTIAL OF THE INNER CONTINENTAL SHELE CAPE FEAR AREA, NORTH CAROLINA: FIRST INTERIM PROGRESS REPORT by Charles W . Hoffman, Patricia E. Gallagher, and Larry Zarra
DIVISION OF LAND RESOURCES Charles H. Gardner, State Geologist
NORTH CAROLINA GEOLOGICAL SURVEY OPEN-FILE REPORT 91-3 1991
srATE OF NORTH CAROLINA JAMES G. MAKI'IN, GOVERNOR
DEPAKfMENT OF ENVIRONMENt HEALTH, AND NATURAL RESOURCES WILLIAM W • COBE~ JR., SECRETARY
CONTENTS Abstract Introduction Previous Work . Methodology..................
1
1 4 5
Results..................................................................................................................................... 6 General.... Lithologic Descriptions and Stratigraphic Correlations Heavy Minerals Summary Acknowledgements References Cited
6 6 13 17 17 17
FIGURES 1 2 3 4 5
Regional location map Detailed location map Heavy-mineral distributions by location and water depth Heavy-mineral distributions by lithology and age of sediment Heavy-mineral distributions by combined age and lithology of sediment
2
3 14 15 16
TABLES 1 Lithologic and stratigraphic data for vibracore samples 2 Sample length, water depth, bulk weight, weight percent plus 10 mesh, and weight percent heavy minerals for vibracore samples
7 10
APPENDIX Grain size distribution of spiral light subsample for non-carbonate vibracore samples
19
Stratigraphic Framework and Heavy-Mineral Resource Potential of the Inner Continental Shelf, Cape Fear Area, North Carolina: First Interim Progress Report by Charles W. Hoffman, Patricia E. Gallagher, and Larry Zarra ABSTRACT
This report presents results from the first phase of a multi-year study to define the geologic framework and assess the potential for heavy-mineral resources of the inner continental shelf off southeastern North Carolina. Examination and determination of weight percent heavy minerals (S.G >2.96) has been completed for 68 samples from 19 vibracores. Upper Cretaceous through Holocene age sediments were recovered in the vibracores. Lithologies include carbonates, muddy quartz sands, and clean quartz sands typical of continental shelf depositional settings. The average weight percent heavy minerals for all samples (as a percent of the total sample) was 0.57 percent with a range from 0.00 percent to 3.69 percent and a standard deviation of 0.59 percent. Although these numbers are not encouraging in terms of the heavy-mineral resource potential, more work is needed before making a definitive assessment. INTRODUCTION
This report presents an interim review of progress for the initial phase of a multi-year research project planned to develop an integrated geologic framework and assess the potential for heavy-mineral resources of the inner continental shelf off southeastern North Carolina (Figures 1 and 2). The overall effort is a joint project by the North Carolina Geological Survey (NCGS), the U. S. Geological Survey (USGS), and North Carolina State University. Partial funding for the work is provided through a cooperative agreement between the U. S. Department of the Interior, Minerals Management Service (MMS) and the Continental Margins Committee of the Association of American State Geologists (AASG). The North Carolina Department of Environment, Health, and Natural Resources is a participant in the program by virtue of a subagreement administered and coordinated for MMS by the University of Texas - Bureau of Economic Geology. The remaining support is being provided by the participating research organizations. The MMS-AASG cooperative agreement covering work reported herein is number 14-12-0001-30432; the subagreement number is 30432-NC. This report presents lithologic, biostratigraphic, and heavy-mineral data derived from study of a set of vibracores (Figures 1 and 2) and compares the results 1
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distribution of heavy minerals according to the age of the sediment. Some differentiation is evident by this graph. Namely, Oligocene age material (despite four carbonate samples weighting the average down) is approximately double any other category. A combination of both age and lithology is used in Figure 5 to categorize heavy-mineral content of these samples. A single core, number 1159 which contains clean quartz sand of Oligocene age, stands out on the graph. Otherwise, no patterns emerge from this graph that are not evident from the preceding graphs of these same parameters. SUMMARY
The 19 vibracores examined as part of this study provide an initial body of data that will be expanded and refined in ongoing and forthcoming phases of this research program. Although it is an important beginning and will be an integral part of the ultimate understanding we expect to reach regarding the geologic framework and mineral resource potential of the study area, no definitive conclusions can be drawn at this early juncture. The general conceptual framework and mineral resource models suggested by previous reconnaissance work in the region have not been appreciably altered or reinforced. ACKNOWLEDGEMENTS
The cooperation of Andrew Grosz, who provided guidance, use of USGS laboratory facilities, and comments on the manuscript is gratefully acknowledged. Steve Snyder of N. C. State University also provided assistance and cooperation for parts of this phase of research and commented on the manuscript. Michael Dixon, geologic technician with the NCGS, performed much of the sample processing. Joel Hutwelker, N. C. State University Minerals Research Laboratory, provided grain size data on the spiral light fraction of the samples. REFERENCES OTED
Grosz, A. E., Berquist, C. R., Jr., and Fischler, C. T., 1990, A procedure for assessing heavy-mineral resources potential of continental shelf sediments, in Berquist, C. R., Jr., editor, Heavy-mineral studies - Virginia inner continental shelf: Virginia Division of Mineral Resources Publication 103, p. 13-30. Grosz, A E., Hoffman, C. W., Gallagher, P. E., Reid, J. C., and Hathaway, J. C., 1990, Heavy-mineral resource potential of surficial sediments on the Atlantic Continental Shelf offshore of North Carolina: a reconnaissance study: North Carolina Geological Survey Open-File Report 90-3, 58 p.
17
Hine, A. C., and Snyder, S. W., 1985, Coastal Lithosome preservation: evidence from the shoreface and inner continental shelf off Bogue Banks, North Carolina: Marine Geology, v. 63, p. 307-330. Meisburger, E. E, 1977, Sand Resources on the inner Continental Shelf of the Cape Fear region, North Carolina, U. S. Army Corps of Engineers, Coastal Engineering Research Center Technical Paper 77-11,20 p. Meisburger, E. E, 1979, Reconnaissance geology of the inner Continental Shelf, Cape Fear region, North Carolina, U. S. Army Corps of Engineers, Coastal Engineering Research Center Technical Paper 79-3, 135 p. Snyder, S. W., 1982, Seismic stratigraphy within the Miocene Carolina phosphogenic province: chronostratigraphy, paleotopographic controls, sea-level cyclicity, Gulf Stream dynamics, and the resulting depositional framework [M. S. Thesis]: Chapel Hill, North Carolina, University of North Carolina at Chapel Hill, 183 p. Zarra, Larry, 1991, Subsurface stratigraphic framework for Cenozoic strata in Brunswick and New Hanover Counties, North Carolina: North Carolina Geological Survey Information Circular 27, 1 sheet.
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10.0
l5..0
21M
Eo- 3s.o
~
~
0
E-i
=
~
~25.0
r.Jil
'iIil30.0
~
40.0
-0.25
-G.2S
0.00
0.00
0.75
0.75
1.75
2.2S
1146.2
2..75
1.75
2.25
2.75
GRAIN SIZE (0)
L2S
1146.4
GRAIN SIZE (0)
L25
APPENDIX - Grain size distribution of spiral light subsample for non-carbonate vibracore samples (continued).
3.25
:US
3.75
3.75
.us
4.2S
>4.25
>4.25
(X)
I\)
1.75
us 2.75 3.2S
3.75
4.25 >4.2S
r:r::I
25.0
5.0
-LOO
0.0
10.0
~
15.0
~
0
!2
1:10.
=20.0
U
L25 2.25
2.75
GRAIN SIZE (0)
1.75
3.2S
3.75
4.25
>4.25
~
~
~ o
1:10.
~
U
15.0
20.0
25.0
0.0 I -1.00
5.0
10.0
I
-1.00
0.0
~
1149.3
GRAIN SIZE (0)
L25
Eo- 30.0
0.75
0.75
Z
0.00
0.00
5.0
10.0
Eo- 30.0
-O.1S
-0.25
~
;
35.0
0.0 .LOG
5.0
10.0
g,..
5:o= 15.0
20.0
25.0
35.0
~
r:r::I
-
=
1:10.20.0 Eo0 15.0
U
~
Eo- 30.0
~ 35.0
riIi1 30.0 U l:lC 25.0 riIi1
3s.o
40.0
1149.1
I -0.25
-0.25
I
0.00
I
0.00
i
I 0.75
0.75
1.75
2.25
1149.2
2.75
1.75
2.25
2.75
GRAIN SIZE (0)
1.25
1149.4
GRAIN SIZE (0)
1.25
Ih»:.:·:·»:jml
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.2S
3.75
3.75
4.2S
4.25
>US
>4.2S
r\)
co
30.0
.0.25
0.00
0.75
us 1.75
us 2.75 3.2S
3.75
4.25
~4.25
-
~
-LOG
0.0
10.0
-D.25
0.00
0.75 1.75 Z.2S
2.75
GRAIN SIZE (0)
1.25
3.25
3.75
4.25
:>4.2S
30.0
40.0
50.0
60.0
0.0 -1.00
; zo.o ~ 10.0
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=
E-t
...... ....
~
Q...
riIi1
Cl
40.0
~ 30.0
Q...
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riIi1 50.0 U
E-c 70.0
~
E-t 60.0
;Z
-0.25
0.00
0.0 ~~~:i:iiiiiii~ -1.00 -0.25 0.00
5.0
80.0
1154.3
GRAIN SIZE (0)
~
70.0
·1.00
0.0
5.0
10.0
~
~ 10.0
zo.O
zs.o
30.0
Cl 15.0
= &3
E-c
Q...
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=:
U
35.0
15.0
E-c 20.0
a
~
~
40.0
35.0
2:25.0
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Siril
~
45.0
4S.O
40.0
1154.1
0.75
0.75
us
2.75
1.75
Z.2S
1154.4
2.75
GRAIN SIZE (0)
1.75
1154.2
GRAIN SIZE (0)
1.25
1.25
APPENDIX - Grain size disbibution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
W
a
2.75 3.25
3.75 4.25
>4.25
U
i
60.0
70.0 ..
0.0 -1.00
10.0
1.75
2.25
··,~·
Ir·y....·.. . . . . ..,.........' Fw.. .w··......·...........·····I···w.·.....w.,
~
~
30.0
Eo- 50.0 Z riIi1 ~ 40.0
60.0
0.0 -LOO
~
~
0.0 I -LOO
I
0.75
I
0.00
I
-0.25
1.75
2.25
2.75
GRAIN SIZE (0)
L25
3.25
3.75
4.25
>4.25
~
=
0.0 -1.00
10.0
J
20.0 10.0
10.0 I
1159.3
GRAIN SIZE (0)
1.25
~
~
1-004
Co:' 20.0 1-004 riIi1
0.75
Eo-
S 30.0
5a20.0
0.00
50.0
~40.0
~ 30.0
-0.25
cr::
riIi1
E-c
~
gs4O.G
U
riIi1 50.0
~
~
~20.0
~30.0
E4M
U
60.0
70.0
~60.0
riIi1so.o
80.0
70.0
1159.1
-0.25
-0.25
0.00
0.00
0.75
0.75
1.75
2.25
1159.2
2.75
1.75
2.25
2.75
GRAIN SIZE (0)
1.25
1159.4
GRAIN SIZE (0)
1.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
>4.25
.us >4.25
U> ........
p..
~
::c to' S
p..
g".
U
20.0
·1.00
-G.2S
o.o~
5.0
10.0
15.0
=
~
Z
25.0
0.00
0.75 L75
2.25
%.75
GRAIN SIZE (0)
:L25
2001R.l
3.25
3.75
4.25
>4.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
NORTH CAROLINA GEOLOGICAL SURVEY OPEN-FILE REPORT 91-3
DIVISION OF LAND RESOURCES DEPARTMENT OF ENVIRONMENT, HEALTH, AND NATURAL RESOURCES
STRATIGRAPHIC FRAMEWORK AND HEAVYMINERAL RESOURCE POTENTIAL OF THE INNER CONTINENTAL SHELE CAPE FEAR AREA, NORTH CAROLINA: FIRST INTERIM PROGRESS REPORT by Charles W . Hoffman, Patricia E. Gallagher, and Larry Zarra
DIVISION OF LAND RESOURCES Charles H. Gardner, State Geologist
NORTH CAROLINA GEOLOGICAL SURVEY OPEN-FILE REPORT 91-3 1991
srATE OF NORTH CAROLINA JAMES G. MAKI'IN, GOVERNOR
DEPAKfMENT OF ENVIRONMENt HEALTH, AND NATURAL RESOURCES WILLIAM W • COBE~ JR., SECRETARY
CONTENTS Abstract Introduction Previous Work . Methodology..................
1
1 4 5
Results..................................................................................................................................... 6 General.... Lithologic Descriptions and Stratigraphic Correlations Heavy Minerals Summary Acknowledgements References Cited
6 6 13 17 17 17
FIGURES 1 2 3 4 5
Regional location map Detailed location map Heavy-mineral distributions by location and water depth Heavy-mineral distributions by lithology and age of sediment Heavy-mineral distributions by combined age and lithology of sediment
2
3 14 15 16
TABLES 1 Lithologic and stratigraphic data for vibracore samples 2 Sample length, water depth, bulk weight, weight percent plus 10 mesh, and weight percent heavy minerals for vibracore samples
7 10
APPENDIX Grain size distribution of spiral light subsample for non-carbonate vibracore samples
19
Stratigraphic Framework and Heavy-Mineral Resource Potential of the Inner Continental Shelf, Cape Fear Area, North Carolina: First Interim Progress Report by Charles W. Hoffman, Patricia E. Gallagher, and Larry Zarra ABSTRACT
This report presents results from the first phase of a multi-year study to define the geologic framework and assess the potential for heavy-mineral resources of the inner continental shelf off southeastern North Carolina. Examination and determination of weight percent heavy minerals (S.G >2.96) has been completed for 68 samples from 19 vibracores. Upper Cretaceous through Holocene age sediments were recovered in the vibracores. Lithologies include carbonates, muddy quartz sands, and clean quartz sands typical of continental shelf depositional settings. The average weight percent heavy minerals for all samples (as a percent of the total sample) was 0.57 percent with a range from 0.00 percent to 3.69 percent and a standard deviation of 0.59 percent. Although these numbers are not encouraging in terms of the heavy-mineral resource potential, more work is needed before making a definitive assessment. INTRODUCTION
This report presents an interim review of progress for the initial phase of a multi-year research project planned to develop an integrated geologic framework and assess the potential for heavy-mineral resources of the inner continental shelf off southeastern North Carolina (Figures 1 and 2). The overall effort is a joint project by the North Carolina Geological Survey (NCGS), the U. S. Geological Survey (USGS), and North Carolina State University. Partial funding for the work is provided through a cooperative agreement between the U. S. Department of the Interior, Minerals Management Service (MMS) and the Continental Margins Committee of the Association of American State Geologists (AASG). The North Carolina Department of Environment, Health, and Natural Resources is a participant in the program by virtue of a subagreement administered and coordinated for MMS by the University of Texas - Bureau of Economic Geology. The remaining support is being provided by the participating research organizations. The MMS-AASG cooperative agreement covering work reported herein is number 14-12-0001-30432; the subagreement number is 30432-NC. This report presents lithologic, biostratigraphic, and heavy-mineral data derived from study of a set of vibracores (Figures 1 and 2) and compares the results 1
o
10
20
30
Kilometers
...•:. /./dl((Y
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@2002
Onslow Bay
~ AREA OF FIGURE 2
71 3:
Nautical
0
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....:•........;"
Figure 1. Map showing location and USGS core number for two vibracores in northern Onslow Bay that were used in this study. 2
4~/34°20'N
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Wilmington
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~ :1 2.96) for each sample expressed as a percent of the total sample. The average weight percent for all samples was 0.57 percent with a range from 0.00 percent to 3.69 percent and a standard deviation of 0.59 percent. Although the average weight percent heavy minerals value is not suggestive of a good potential for heavy-mineral resources, conclusive judgment of the potential for resources based on such a small and diverse sampling over such a large area would be premature. Determination of the quality of the heavy-mineral concentrates (that is the abundance of the various species) is yet to be done. Additionally, many more vibracores from the study area, some representing stratigraphic units or depositional settings not tested by this initial set of cores, are yet to be examined. The weight percent heavy minerals reported for the Cape Fear area in Grosz and others (1990) are in line with the values obtained in this initial work. As a result of that earlier work, one of the chief premises of continued research in this region is that unique conditions that are favorable for the development of heavymineral deposits may exist locally and that the potential for heavy-mineral resources in the area can not be dismissed without more thorough testing. The weight percent heavy minerals data for this first set of vibracores is illustrated versus several parameters in Figures 3, 4, and 5. In most cases, the number of members (n) in a given class are not sufficient to permit meaningful interpretations regarding the heavy-minerals content of that group. Classes having less than three members were not considered. These data are displayed simply for the purpose of organizing the results according to a variety of logical parameters. As additional vibracores are opened and data are added to these or similar displays, systematic patterns of heavy-minerals distribution may emerge. As shown in Figure 3, the distribution of heavy minerals does not seem to be significantly affected by either the geographic location of or the water depth at the vibracore site. In Figure 4, part A, the distribution of heavy minerals is shown versus lithology. Not surprisingly, the heavy-mineral content of quartz sands is markedly higher than that of the carbonates. Figure 4, part B, presents the 13
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.
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..
(0=12)
LONG BAY
m
. ~~
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LOCATION
(0=18)
(0=38)
FRYING ONSLOW PAN SHOALS BAY
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0
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01
CLEAN QUARTZ SAND (0=21)
Bolol Pleistocene (n=8)
Pliol Pleistocene (n=20)
AGE OF SEDIMENT
(n=14)
(n=19) (0=3)
(n=19)
LITHOLOGY
PUoc:ene
Oligocene Upper Cretaceous
CARBONATE
0.00
~ 0.20
~ 0.30
~
~
~ Q".
0.00
MUDDY QUARTZ SAND (n=28)
0.50
u ~ 0.40
~
Z
E-c
=
~
~
~
0.60
0.70
~
"~ :i!1
0.80
r:n ~
0.10
T
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
Figure 4. Distribution of heavy minerals (as weight percent of bulk sample) by A) lithology of sample, and B) age of sediment in sample - classes with less than 3 members (Middle Eocene and Miocene) not shown.
~
~
~
..
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~
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c
:i
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A)
B)
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=
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16
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distribution of heavy minerals according to the age of the sediment. Some differentiation is evident by this graph. Namely, Oligocene age material (despite four carbonate samples weighting the average down) is approximately double any other category. A combination of both age and lithology is used in Figure 5 to categorize heavy-mineral content of these samples. A single core, number 1159 which contains clean quartz sand of Oligocene age, stands out on the graph. Otherwise, no patterns emerge from this graph that are not evident from the preceding graphs of these same parameters. SUMMARY
The 19 vibracores examined as part of this study provide an initial body of data that will be expanded and refined in ongoing and forthcoming phases of this research program. Although it is an important beginning and will be an integral part of the ultimate understanding we expect to reach regarding the geologic framework and mineral resource potential of the study area, no definitive conclusions can be drawn at this early juncture. The general conceptual framework and mineral resource models suggested by previous reconnaissance work in the region have not been appreciably altered or reinforced. ACKNOWLEDGEMENTS
The cooperation of Andrew Grosz, who provided guidance, use of USGS laboratory facilities, and comments on the manuscript is gratefully acknowledged. Steve Snyder of N. C. State University also provided assistance and cooperation for parts of this phase of research and commented on the manuscript. Michael Dixon, geologic technician with the NCGS, performed much of the sample processing. Joel Hutwelker, N. C. State University Minerals Research Laboratory, provided grain size data on the spiral light fraction of the samples. REFERENCES OTED
Grosz, A. E., Berquist, C. R., Jr., and Fischler, C. T., 1990, A procedure for assessing heavy-mineral resources potential of continental shelf sediments, in Berquist, C. R., Jr., editor, Heavy-mineral studies - Virginia inner continental shelf: Virginia Division of Mineral Resources Publication 103, p. 13-30. Grosz, A E., Hoffman, C. W., Gallagher, P. E., Reid, J. C., and Hathaway, J. C., 1990, Heavy-mineral resource potential of surficial sediments on the Atlantic Continental Shelf offshore of North Carolina: a reconnaissance study: North Carolina Geological Survey Open-File Report 90-3, 58 p.
17
Hine, A. C., and Snyder, S. W., 1985, Coastal Lithosome preservation: evidence from the shoreface and inner continental shelf off Bogue Banks, North Carolina: Marine Geology, v. 63, p. 307-330. Meisburger, E. E, 1977, Sand Resources on the inner Continental Shelf of the Cape Fear region, North Carolina, U. S. Army Corps of Engineers, Coastal Engineering Research Center Technical Paper 77-11,20 p. Meisburger, E. E, 1979, Reconnaissance geology of the inner Continental Shelf, Cape Fear region, North Carolina, U. S. Army Corps of Engineers, Coastal Engineering Research Center Technical Paper 79-3, 135 p. Snyder, S. W., 1982, Seismic stratigraphy within the Miocene Carolina phosphogenic province: chronostratigraphy, paleotopographic controls, sea-level cyclicity, Gulf Stream dynamics, and the resulting depositional framework [M. S. Thesis]: Chapel Hill, North Carolina, University of North Carolina at Chapel Hill, 183 p. Zarra, Larry, 1991, Subsurface stratigraphic framework for Cenozoic strata in Brunswick and New Hanover Counties, North Carolina: North Carolina Geological Survey Information Circular 27, 1 sheet.
18
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4.25
>4.25
....JVi..~.
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5.0
10.0
5t
~
t.:l
-
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=
~ l:lo.
U
~
0.0 -LOO
5.0
10.0
15.0
E-t Z 20.0
;
4.25
3.25
3.75
4.25
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35.0
40.0
0.0
5.0
10.0
15.0
20.0
~
~
0 .....
=
E-i
g:
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-1.00
0.0 -1.00
5.0
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738.2
GRAIN SIZE (0)
us
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.2S
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
-a.
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2.75
GRAIN SIZE (0)
L25
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GRAIN SIZE (0)
1.25
738.3
3.15
3.25
3.75
3.75
4.25
4.25
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15.0
20.0
25.0
30.0
50.0
=...
~
riIi:l
E-t
0.0 -1.00
10.0 5.0
20.0 15.0
25.0
~ 30.0
40.0
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0.00
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0.75
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738.4
2.75
1.75
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2.75
GRAIN SIZE (0)
1.1S
771.1
GRAIN SIZE (0)
1.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
:U5
3.75
4.25
4.25
>4.25
>4.25
I\) I\)
~
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5.0
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0.0 -1.00
10.0
15.0
20.0
25.0
;,
t'
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=
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-0.25
0.00
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0.00
..................
0.0 -1.00
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10.0
15.0
20.0
25.0
30.0
35.0
~:
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0.75
0.75
1.75
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2.75
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GRAIN SIZE (0)
1.25
771.4
GRAIN SIZE (0)
1.25
771.2
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3.2S
3.75
3.75
4.25
4.25
>4.25
>4..25
., .......
~
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0.0 -1.00
5.0
10.0
15.0
20.0
20.0
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=
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0.00
0.75
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1.75
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2.75
GRAIN SIZE (0)
1.25
773.1
GRAIN SIZE (0)
1.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
I\) U)
I
1.25 1.75
nwzq·wwtit·wu •••• \
0-75 2.75
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..... .us >4.25
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>4.25
~
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0.0 -LOO
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sa
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0.0
s.o
10.0
15.0
20.0
25.0
L2S
1.75
2.25
GRAIN SIZE (0)
~ ~
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= sa
0.0 -1.00
5.0
15.0 10.0
20.0
25.0
~
40.0 35.0
~ 30.0
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35.0
40.0
45.0
777.1
3.25
50.0
0.00
2.75
GRAIN SIZE (0)
2.25
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0.75
5.0
10.0
~ 30.0
t3
~
0.00
-0.25
Si
20.0 15.0
25.0
30.0
35.0
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0
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50.0
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0.00
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773.3
2.75
1.75
2.25
2.75
GRAIN SIZE (0)
1.25
777.2
GRAIN SIZE (0)
l.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
~
N
40.0
10.0
~
50.0
==
~
5
Eo-
~
Cll: 'iii!
0.0 -1.00
10.0
20.0
30.0
U 40.0
~
~
60.0
0.0 -1.00
20.0
~
= sa
Eo- 30.0
I:lot
=
~ 50.0
2.75
3.2S
3.75
4.25 :>4.25
~ ~
~
U
-0.25
-0.25
0.00
0.00
0.75
0.75
1.75
us
1.75
us
2.75
GRAIN SIZE (0)
1.25
779.1
GRAIN SIZE (0)
1.25
3.25
3.75
4.25
:>4.2S
20.0
30.0
40.0
50.0
==
sa'iii!
~
I:lot
-1.00
5.0 0.0 I
10.0
20.0 15.0
25.0
30.0
=
~ 40.0 'iii! 35.0 U
45.0
50.0
0.0 -1.00
~ 10.0
'iii!
Co'
-
Eo-
=
~
70.0
~ 60.0 60.0
80.0
70.0
777.3
-0.25
I
-0.25
0.75
0.00
0.75
I'.,.,.·wm'fw
0.00
2.25
2.75
1.75
2.25
779.2
2.75
GRAIN SIZE (0)
1.25
........'"
1.75
777.4
GRAIN SIZE (0)
1.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
r\)
01
~
25.0 .,.
0.0 -LOO
10.0
%0.0
~
riIiiI
I-f
0
~
U
-1.GO
0.0
5.0
10.0
15.0
= =-
~20.0
~
~
~
I-f
r;
=Eo-
30.0
U40.0
I:IC
-O.2S
-O.2S
0.00
0.00
0.75
0.75
1.75
2.25 2.75
1.75
2.25
2.7S
GRAIN SIZE (0)
1.25
783.2
GRAIN SIZE (0)
1.25
3.25
3.75
4.1S
>4.2S
:us
3.75
.us
>US
zs.o
15.0
30.0
-LOG
0.0
s.o
10.0
~
~
~
I-f
:: Co:)
~
=--
~
=:
U
0.0 -LOO
5.0
10.0
15.0
20.0
~ 25.0
~
~
5:2
!C
~20.0 =--
U
~
~30.0
Z
Eo- 50.0
~
35.0
60.0
779.3
-0.25
-O.2S
0.00
0.00
0.75
0.75
1.75
2.25
783.1
2.75
1.75
2.2S
2.75
GRAIN SIZE (0)
1.25
783.3
GRAIN SIZE (0)
1.25
APPENDIX - Grain size distribution of spiral light subsample for non-carbonate vibracore samples (continued).
:us
3.25
3.7S
3.75
4.2S
4.2S
>4.25
>4.25
ro
en
~
~
!C0
~
~
I 1.75
us 2.75
1.25
30.0
2.75
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
~
e-. ~ U =: riIi1
0.0 -1.00
GRAIN SIZE (0)
~
-0.25
I
-LOO -0.25
0.0
5.0
15.0
20.0
25.0
30.0
5.0
0
e-. ::c
J
-1.00
~ 10.0
2.2S
3.25
10.0
15.0
20.0
1.75
1140.2
GRAIN SIZE (0)
1.25
40.0
0.75
0.75
10.0 5.o 0.0
15.0
20.0
30.0 25.0
35.0
0.00
0.00
40.0 35.0
40.0
-0.25
-0.25
w,
i ·.. .
sa ~
~
~
=
~
fj
50.0 45.0
35.0
-1.00
0.0
5.0
10.0
~25.0
~
~
~
~
15.0
E
EoZ 20.0 riIi1
25.0
783.4
0.00
0.00
0.75
0.75
".'
3«
. . , "....,
1140.1
::.
1.75
2.25
2.75
GRAIN SIZE (0)
US
1140.3
1.75 us 2.75 GRAIN SIZE (0) 1.25
..
_
'":':-:-:-:-:-:-l~~:6~~::t ~:"
APPENDIX - Grain size distribution of spiral light subsample for non-carbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
4.25
:>4.25
>4.25
......
I\)
20.0
30.0
35.0
-LOO
0.0 I
5.0
10.0
~
~
t:
~
-1.00
0.0
5.0
10.0
15.0
20.0
=
U
~ 25.0
Z
Eo-
~
~
~ 15.0
~
=
U
\"iIil25.0
~30.0
35.0
-0.25
I -0.25
0.00
0.00
0.75
0.75 1.75
?.~
us 2..75
1.75
%.25 2..75
GRAIN SIZE (0)
L25
...
1146.3
:us
3.25
3.75
3.75
•
.us
4.25
-.
~
.-'
>4.25
>4.25
-:Ii:::I~f?lW*~1~·"'''··1-'''''"'''·u""".~,-,
GRAIN SIZE (0)
1.25
,..........ZCW··f..-.v;;
1146.1
35.0
40.0
30.0
~
0
S3
Eo-
-LOO
0.0
5.0
10.0
15.0
20.0
=
~ ~
~25.0
~
-1.00
0.0
5.0
10.0
l5..0
21M
Eo- 3s.o
~
~
0
E-i
=
~
~25.0
r.Jil
'iIil30.0
~
40.0
-0.25
-G.2S
0.00
0.00
0.75
0.75
1.75
2.2S
1146.2
2..75
1.75
2.25
2.75
GRAIN SIZE (0)
L2S
1146.4
GRAIN SIZE (0)
L25
APPENDIX - Grain size distribution of spiral light subsample for non-carbonate vibracore samples (continued).
3.25
:US
3.75
3.75
.us
4.2S
>4.25
>4.25
(X)
I\)
1.75
us 2.75 3.2S
3.75
4.25 >4.2S
r:r::I
25.0
5.0
-LOO
0.0
10.0
~
15.0
~
0
!2
1:10.
=20.0
U
L25 2.25
2.75
GRAIN SIZE (0)
1.75
3.2S
3.75
4.25
>4.25
~
~
~ o
1:10.
~
U
15.0
20.0
25.0
0.0 I -1.00
5.0
10.0
I
-1.00
0.0
~
1149.3
GRAIN SIZE (0)
L25
Eo- 30.0
0.75
0.75
Z
0.00
0.00
5.0
10.0
Eo- 30.0
-O.1S
-0.25
~
;
35.0
0.0 .LOG
5.0
10.0
g,..
5:o= 15.0
20.0
25.0
35.0
~
r:r::I
-
=
1:10.20.0 Eo0 15.0
U
~
Eo- 30.0
~ 35.0
riIi1 30.0 U l:lC 25.0 riIi1
3s.o
40.0
1149.1
I -0.25
-0.25
I
0.00
I
0.00
i
I 0.75
0.75
1.75
2.25
1149.2
2.75
1.75
2.25
2.75
GRAIN SIZE (0)
1.25
1149.4
GRAIN SIZE (0)
1.25
Ih»:.:·:·»:jml
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.2S
3.75
3.75
4.2S
4.25
>US
>4.2S
r\)
co
30.0
.0.25
0.00
0.75
us 1.75
us 2.75 3.2S
3.75
4.25
~4.25
-
~
-LOG
0.0
10.0
-D.25
0.00
0.75 1.75 Z.2S
2.75
GRAIN SIZE (0)
1.25
3.25
3.75
4.25
:>4.2S
30.0
40.0
50.0
60.0
0.0 -1.00
; zo.o ~ 10.0
~zo.o
=
E-t
...... ....
~
Q...
riIi1
Cl
40.0
~ 30.0
Q...
~
riIi1 50.0 U
E-c 70.0
~
E-t 60.0
;Z
-0.25
0.00
0.0 ~~~:i:iiiiiii~ -1.00 -0.25 0.00
5.0
80.0
1154.3
GRAIN SIZE (0)
~
70.0
·1.00
0.0
5.0
10.0
~
~ 10.0
zo.O
zs.o
30.0
Cl 15.0
= &3
E-c
Q...
Siril
=:
U
35.0
15.0
E-c 20.0
a
~
~
40.0
35.0
2:25.0
~
Siril
~
45.0
4S.O
40.0
1154.1
0.75
0.75
us
2.75
1.75
Z.2S
1154.4
2.75
GRAIN SIZE (0)
1.75
1154.2
GRAIN SIZE (0)
1.25
1.25
APPENDIX - Grain size disbibution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
4.25
>4.25
>4.25
W
a
2.75 3.25
3.75 4.25
>4.25
U
i
60.0
70.0 ..
0.0 -1.00
10.0
1.75
2.25
··,~·
Ir·y....·.. . . . . ..,.........' Fw.. .w··......·...........·····I···w.·.....w.,
~
~
30.0
Eo- 50.0 Z riIi1 ~ 40.0
60.0
0.0 -LOO
~
~
0.0 I -LOO
I
0.75
I
0.00
I
-0.25
1.75
2.25
2.75
GRAIN SIZE (0)
L25
3.25
3.75
4.25
>4.25
~
=
0.0 -1.00
10.0
J
20.0 10.0
10.0 I
1159.3
GRAIN SIZE (0)
1.25
~
~
1-004
Co:' 20.0 1-004 riIi1
0.75
Eo-
S 30.0
5a20.0
0.00
50.0
~40.0
~ 30.0
-0.25
cr::
riIi1
E-c
~
gs4O.G
U
riIi1 50.0
~
~
~20.0
~30.0
E4M
U
60.0
70.0
~60.0
riIi1so.o
80.0
70.0
1159.1
-0.25
-0.25
0.00
0.00
0.75
0.75
1.75
2.25
1159.2
2.75
1.75
2.25
2.75
GRAIN SIZE (0)
1.25
1159.4
GRAIN SIZE (0)
1.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
3.25
3.25
3.75
3.75
4.25
>4.25
.us >4.25
U> ........
p..
~
::c to' S
p..
g".
U
20.0
·1.00
-G.2S
o.o~
5.0
10.0
15.0
=
~
Z
25.0
0.00
0.75 L75
2.25
%.75
GRAIN SIZE (0)
:L25
2001R.l
3.25
3.75
4.25
>4.25
APPENDIX - Grain size distribution of spiral light subsample for non-earbonate vibracore samples (continued).
