4. SITE 185
The Shipboard Scientific Party1

SITE DATA
Date Occupied: 5-7 Aug 71.
Position:
54°25.73'N
169°14.59'W.
Water Depth: 2110 meters.
Penetration: 728 meters.
Number of Holes: One.
Number of Cores: 27.
Total Core Recovered: 98 meters.
Acoustic Basement:
Depth: greater than 1.5 second
Nature: Unknown
Velocity: Unknown.
Age of Oldest Sediment: Not determinable, but must be
upper Miocene or older.
Basement: Not determinable.
SUMMARY
Site 185 is located on the southern flank of the broad
spur separating Bristol and Bering canyons, southeastern
Bering Sea, in water 2110 meters deep.
The drilled and cored sedimentary sequence consists of
728 meters of Holocene, Pliocene, and upper Miocene
hemipelagic clay-rich diatom ooze and diatomaceous silty
clay or clayey silt. Thin, terrigenous sand and silt beds, a
few ash layers, and some limestone beds also occur. A
gradual decrease in diatom content and enrichment in clay
takes place between 600 meters and 728 meters.
The terrigenous fraction is most likely derived from aterrane underlain by volcanic rocks or rocks rich in volcanic
debris. The upper portion of the section (above 250 m at
Core 10) contains discrete beds of pyroclastic and volcanoclastic debris composed of glass- and feldspar-rich sandand sandy silt, thin ash layers, scattered erratics, andpumice fragments. Additionally, above 250 meters the'section locally contains up to 20 percent glass as a1
David W. Scholl, U.S. Geological Survey, Menlo Park, California; Joe S. Creager, University of Washington, Seattle, Washington; Robert E. Boyce, Scripps Institution of Oceanography, La
Jolla, California; Ronald J. Echols, University of Washington,
Seattle, Washington; Timothy J. Fullam, Standard Oil Company ofCalifornia, La Habra, California; John A. Grow, Massachusetts
Institute of Technology, Cambridge, Massachusetts; Itaru Koizumi,
Osaka University, Osaka, Japan; Homa J. Lee, Naval Civil Engineering Laboratory, Port Hueneme, California; Hsin Yi Ling, Universityof Washington, Seattle, Washington; Richard J. Stewart, Universityof Washington, Seattle, Washington; Peter R. Supko, Scripps
Institution of Oceanography, La Jolla, California; Thomas R.
Worsley, University of Washington, Seattle, Washington.

constituent of the terrigenous fraction. Unlike Site 184,
only a few neritic diatoms occur and these are scatteredthroughout the sediment sequence.
Because the sediments at this site are characterized by
gradual lithologic and age changes, with superimposedminor fluctuations in the relative amounts of terrigenous
and pelagic components, the section was not subdivided
into units. However, from 0 to 587 meters (through Core17) the sediments are similar to Unit A defined at Site 184.
The sediments of the lower portion of the hole from 644 to
728 meters are either Site 184, Unit B equivalents (in whichcase they are less indurated, less extensively burrowed, andcontain more diatom remains) or are a thicker equivalent of
the thin transition zone separating Units A and B at Site184.
At Site 185 the bottom-simulating reflector (BSR)
occurs at 670 meters and is apparently coincident (unlike
Site 184) with a 10- to 15-meter thick section of gaseous(virtually all methane) sediment and a lithologic transition
from terrigenous-rich diatomaceous deposits to a virtually
unfossiliferous siltstone sequence.
The lithologic transition found near the BSR may
represent an upward migrating zone of diagenesis involving
the alteration of former detritus-rich diatomaceous beds tosiltstone or claystone units that bear only vestiges of its
original siliceous microflora. The lithologic transition may
in part account for some of the reflected energy encountered at the bottom-simulating horizon and may belocally associated with gas accumulations (see Scholl andCreager, and Fullam et al., this volume).
BACKGROUND AND OBJECTIVES
Description
Site 185, at a water depth of 2110 meters, is located on
the southern flank of the broad spur separating Bristol andBering canyons, southeastern Bering Sea (Figure 1). Acoustically, three stratigraphic units are distinguishable: (1) asurface mantling unit (160 m thick), (2) an underlying
layered sequence characterized by strong internal reflecting
horizons (600-700 m thick), and (3) a lower stratified
sequence having rather weak internal reflecting surfaces.
Separating Units 2 and 3 is the presumed "clathrate"
reflecting surface, a surface that crosses phase returns that
presumably trace bedding planes. This surface follows the
topography of the sea floor at a subbottom depth close to670 meters (0.82 sec), which is close to the theoretical baseof a clathrated zone, if, in fact, one exists.
Objectives
The objectives sought at Site 185 were identical to thosedescribed for Site 184. The primary reason for occupying
Site 185 was to confirm or challenge the results obtained at
Site 184, which needed clarification.

169

SITE 185

recovered Holocene sediment). The 2120 meters below drill
floor, or 2110 meters below sea level, is the accepted depth
for this site.
The section penetrated from the bottom to 690 metersconsists of diatomaceous ooze and diatom-rich silty clay
with some pumice and ash and occasionally a hard-to-drill
layer. From 690 meters to the bottom of the hole at 728
meters the sediment is silty clay.
Core 20 (662-671 m) recovered 9.5 meters of sediment
which contained methane and traces of other gases, as was
the case also in Core 21 (671-680 m). The special pressure
core barrel was used for Cores 22 (680-683 m), 24(690-691 m), and 27 (727-728 m) without success. Possible
sources of trouble include: a) changes made in theconfiguration to accommodate the float valve in the drill
string; 2) insufficient clearance between piston and barrell(Corrected before Core 27); 3) possible failure of the
flapper valve to seat properly. A coring summary is given in
Table 1.

BERING SHELF

LITHOSTRATIGRAPHY
50°

Figure 1. Base map showing the location of Site 185.
OPERATIONS
Pre- and Post-drilling Survey

Site 185 was approached with a ship's heading of 122°T.
Continuing on across the site, the ship turned to a headingof 048°T (the reciprocal of the heading of the reference
profile collected by D. W. Scholl on 1 Jul 65). After about
three quarters of an hour at 5 knots on this heading, theship returned on a course of 246°T to a DR site picked at
54°26.5'N, 169°13.2'W. The beacon was dropped on the
fly during the second pass over the chosen site, at 0500 hrs
on 5 Aug 71. The finally accepted satellite position is:
54°25.73'N; 169°14.59'W. The reference seismic profile isshown in Figure 2. The air-gun profile (Figure 3) taken
crossing the site and then returning to it revealed astratigraphic section similar to the reference profile and one
which appeared to have a good "clathrate-type" reflective
structure.
No post-drilling survey was deemed necessary. A map
showing the pre-drilling survey track is given on Figure 4.
Drilling Program

Site 185 was occupied from 0500 hrs 5 Aug 72 (beaconaway) until 0930 hrs 7 Aug 71 with alternating coring andwashing from the sea floor to a subbottom depth of 728
meters. At this depth a stiff clay silt caused the special"clathrate" core barrel to jam, shearing the pin in the sandline recovery mechanism, forcing abandonment of the hole.
Using Matthews Tables and information from the U.S.
Navy Undersea Research and Development Center, thesonic depth of 1135 fms was corrected to 2094 meters
giving a water depth of 2100 meters and a drill-floor depthof 2110 meters. This compares with 2120 meters below
drill floor established on the basis of the first core (which

170

The sediments at Site 185 are characterized by graduallithologic and age changes and by superimposed minor
fluctuations in the relative amounts of the terrigenous andpelagic components. Lack of distinct lithologic changes
discourages subdividing the section into separate units.
Except for thin, wholly terrigenous sand and silt beds, a
few ash layers, and some limestone beds, the entire section
is diatomaceous with a gradual decrease in diatom content
from about 600 meters to T.D. The terrigenous fraction of
the cored and drilled hemipelagic muds probably is largely
derived from a volcanic terrane. The upper portion of thesection, above approximately 250 meters below bottom(Core 10), contains discrete beds of pyroclastic andvolcanoclastic debris composed of glass- and feldspar-richsand and sandy silts, thin ash layers, and scattered erratic
pebbles, some of which are pumice. In addition, sediments
above about 250 meters locally contain up to 10% glass as aconstituent of the terrigenous fraction.
Dominant Lithology

From 0 to 653 meters below bottom, the terrigenous
and pelagic components are subequal. Diatom content
ranges from 40% (diatomaceous silty clay or diatomaceous
clayey silt) to a maximum of 90% (clay-rich diatom ooze)
and averages about 65%. Typical colors are dark grayish
olive, grayish olive, dark olive gray, light olive gray, andolive brown, the darker colors generally being associatedwith larger amounts of terrigenous silt and clay. The
silt/clay ratio of the terrigenous component averages about
1:2.
Below about 600 meters the diatom content decreases,caused in part by the dissolution and alteration of the
diatoms. From about 667 meters below bottom (Core 20)
to T.D. a few zones devoid of diatoms were observed;
however, most smear slides contained at least a small
percentage of diatom fragments in various stages ofalteration. The lower 3.6 meters of Core 20, which was
examined in greatest detail, consists of zones of altereddiatoms, zones of well-preserved diatoms, and zones without diatoms (Section 4), although there were no obvious

SITE 185

Near Site 185

>.r "

%y

Figure 2. Reference seismic reflection profile, collected by D. W. Scholl, 1 Jul 65.

-4.0

color or textural differences in the sediments. At T.D. (728m below bottom) the Core 27 core catcher sample
contained few, if any, diatoms, and consisted of indurated
dark olive gray silty clay. Sponge spicules (up to 10%) are alocally important constituent of the diatomaceous
sediments.
The terrigenous component throughout the section
contains abundant Plagioclase grains (in the silt fraction),many of which are zoned. Based on this observation andthe occurrence of glass in the terrigenous admixture, it
seems reasonable to conclude that the source terrane wasunderlain by volcanic rocks and that it included active
volcanoes. Reworked Cretaceous nannofossils strongly
imply that the mainland of Alaska was part of the terrane.

fine-grained glass shards and/or pumice pebbles. Typicalcolors are light brownish gray to pale yellowish brown. The
fifth ash (Core 7, 131.5 m below bottom) is transitional
between the light-colored ashes and the volcanic sands andcontains 25% or more lithic fragments as well as somediatoms.
3. Pumice fragments. These occur singly and in zones,
are usually rounded, and are up to 2 cm in" diameter.
Ice-rafted (?) erratics of other compositions occur in thesame interval (above 250 m) and may be of nonvolcanic
origin. Concentrations of erratics occur at 96 to 100 meters(Core 6), 132 to 133 meters (Core'7), and about 168
meters (Core 8).

Volcanic Constituents
The upper 250 meters of the drilled and cored section
contain three types of volcanic material occurring as
discrete beds.
1. Volcanic sand and sandy silt. These units contain 20
to 40% light- and dark-colored glass (frequently iron oxide
stained), feldspar, volcanic lithic fragments, and associatedheavy minerals. Many of the glass shards and lithic
fragments are altered. The sands and silts occur both as
isolated pods and streaks in disturbed cores and as distinct
beds from 1 to 20 cm thick. Some size grading wasobserved in the thicker units (Core 10, 225 to 225.3 m
below bottom). Colors range from blackish red to black.
2. Vitric ash beds. Five ash layers up to 5 cm thick wereobserved. Four of the ashes are composed of virtually 100%

Limestones
Local concentrations of finely crystalline calcium carbonate occur from about 171 meters to T.D. They arefound as pods, as zones in silty clay, and as limestone beds
up to 50 cm thick. Some of the limestone contains
nannofossils and/or scattered diatom fragments.
General Comments
Site 185 is approximately 150 km northeast of Site 184,
and the sediments recovered at the two sites are very
similar. However, the sediments at Site 185 contain agreater amount of terrigenous material. Whereas the average
diatom percentage in the pelagic sequence at Site 184 wasabout 80%, the equivalent unit at Site 185 contains anaverage of only about 65% diatoms. The difference may be

171SITE 185

2-way
time,
sec.
-2

Figure 3. Glomar Challenger air-gun profile coming onto Site 185.
explained by the closer proximity of the Alaska mainlandand Bering Sea shelf to Site 185.
The first seventeen cores (0-587 m) contain sediments
comparable to Unit A defined at Site 184. The remainderof the cores (644-728 m) contain either Site 184, Unit B
equivalents (in which case they are less indurated, lessextensively burrowed, and contain more diatom remains) ora thicker equivalent of the mudstone separating Units A
and Bat Site 184.
PHYSICAL PROPERTIES

Physical properties measured at Site 185 include bulk
density, water content, natural gamma radiation, acoustic
velocity, and vane shear strength. Bulk density wasmeasured with the GRAPE system, calculated from tests onsealed samples taken to a shore laboratory, and, for the172

harder materials, measured by the water displacement
method. The bulk densities and the acoustic velocities arepresented on the site summary sheet.
Bulk Density
GRAPE densities were measured to a sediment depth ofabout 230 meters and also on Core 20 in the vicinity of 670
meters. The remainder of the cores were badly fractured or
discontinuous and would have yielded invalid density
measurements. The GRAPE measurements are supplemented by the shore laboratory values. At great depths the
GRAPE measurements are supplemented by the water
displacement values.
The densities obtained indicate a rather uniform sediment of low density (1.6 g/cm3) for the zone 0 to 230
meters and a relatively dense (1.7-1.8 g/cm3) zone from
650 to 730 meters. At around 665 meters, a short (4 m),

SITE 185
169°25'W

169°20'W

169°10'W

169°05'W|54°30'N

0305 L/5 AUG 71
122°

54°25'N

Figure 4. Glomar Challenger pre-drilling survey track, Site 185.
disturbed section containing gas yielded a mean density of
1.5 g/cm3.
Acoustic Velocity
The acoustic velocities measured with the Hamilton
Frame indicate the existence of two zones. The firstextends from 0 to 650 meters and is characterized by an
acoustic velocity which gradually increases from about 1.5
to 1.75 km/sec. The second zone extends from 650 meters
to the bottom of the hole and has an acoustic velocity of 2
to 2.05 km/sec. A rapid increase in velocity occurs over thetransition zone, 650-670 meters.
Summary

The physical property data (primarily the acoustic
velocities) suggest the existence of two zones. The upperzone extends from 0 to 650 meters and has a low density(1.6 g/cm3) and an acoustic velocity of 1.5-1.75 km/sec.
The lower zone extends from about 670 meters to thebottom of the hole. It has a density of 1.7-1.85 g/cm3 andan acoustic velocity of 2-2.05 km/sec.
PALEONTOLOGY

Sediments at Site 185 are lithologically similar to thoseobserved at Site 184 and thus provide an opportunity toreexamine the stratigraphic occurrence of micro fossils, their
zonations, or an individual taxon. Ages of diatomaceous
sediments recognized here range from Holocene to late
Miocene. Starting from Core 18, and particularly from Core21, down to the bottom of the hole, only fragments ofdiatom valves were encountered.

Diatoms dominate the microfossil assemblage, whilesilicoflagellates show a slight increase in numbers andvarieties over previous Sites 183 and 184. Both radiolaria
and nannofossils are rather scarce throughout.
Foraminifera

Dominantly calcareous assemblages occur down throughCore 7. Cores 8 and 10 have only arenaceous assemblages.
Deeper cores were not examined.
Sinistral Globorotalia (T.) pachyderma populations
occur down through Core 5, indicating upper and middle
Pleistocene, and dominantly dextral populations occur inCores 6 and 7, indicating lower Pleistocene or older.
Calcareous benthonic assemblages are usually dominatedby Elphidium batialis and Islandiella teretis as at Site 184.
Undoubted displaced forms were not found. Martinottiellacommunos has its highest occurrence in Core 7, which iswithin the Pliocene according to diatoms.
Calcareous nannoflora
Site 185 contains a sparse assemblage of Pleistocene
coccoliths in Cores 1 to 3. Cores 4 to 7 contain rare
specimens of non-age-diagnostic species dominated by
Coccolithus pelagicus. Below Core 7, Site 185 is essentiallybarren of nannofossils except for isolated specimens of
Watznaueria probably derived from a Mesozoic outcrop on
the shelf.
Small (3-5µ) calcite needles were observed in Core 4 inassociation with partially dissolved placoliths. The needles
are probably isolated elements from decomposed placoliths.
The needles were noted in lower cores without associated173

SITE 185
TABLE 1
Core Summary - Site 185

Cored Interval
Below Bottom

Recovered
Cored
(m)

(m)

(%)

9-16
16-25

9
7
9

9.5
1.5
1.5

105.6
21.4
16.7

35-44

9

8.4

93.3

63-72

9

2.3

25.6

6

91-100

9

9.5

105.6

Wash
7
Wash

129-138

9

7.0

77.8

8

167-176

9

6.4

71.1

213-222222-231

9

1.5

9

4.9

16.7
54.4

269-278

9

2.2

24.4

335-344

9

2.2

24.4

Diatoms
The vertical distribution of important taxa at the site isgiven in Table 3, Chapter 30. The species composition in
the planktonic marine diatom assemblage is rather amonotonous subarctic type and is similar to that of Site
184. Note here that Unit II, which is of Pliocene age,consists of only two samples and is very thin comparedwith that of the previous site.
A few benthonic to sublittoral species are present insamples throughout the core levels, but they are never asabundant as in the Pliocene section at Site 184.

372-381381-390

9
9

2.2
1.2

24.2
13.3

CORRELATION BETWEEN REFLECTION PROFILEAND STRATIGRAPHIC COLUMN

447-456

9

2.0

22.2

513-522

9

2.3

25.6

578-587

9

3.2

35.6

18
19
20
21
22

644-653653-662662-671671-680680-683

9
9
9
9
3

23
24

683-690690-6917
1

25

691-699

8

30.0
28.9
105.6 Gas
3.7
41.1 Gas
Special Clathrate
Corer Used
Only small section
recovered
2.0
28.6
0.2
20.0
Clathrate Corer
Used
2.2
27.5

718-727727-728

9
1

7.0

216

98.0

The reflection profile taken by D. W. Scholl (in 1965)
which was used for the selection of Site 185, is shown in
Figure 5 along with the stratigraphic column and physicalproperties. The profile, similar to Site 184, again shows finescale internal reflectors well developed in the upper 0.8 sec
and less well developed below the bottom simulatingreflector (BSR, as discussed under Site 184), which cuts
discordantly through the internal layers. Although thechange in lithology across the BSR is more gradual here
than at Site 184, the appearance of some gas at 670 meters,
along with distinct increases in the lithification, bulk
density, and velocity, seems to correlate with the BSR atabout 0.82 sec.
Although the reflection profile in Figure 5 does notsuggest any other significant acoustical subdivisions, theGlomar Challenger's profile coming onto Site 185 (seeFigure 3) and other profiles in this area clearly show a"surface mantling" unit between the bottom and about 0.2
sec. The base of this surface mantling unit may correlatewith some hard drilling at 158 meters; although a time
hiatus occurs here, no significant lithologic change wasobserved between the recovered cores at 129 to 138 meters(Core 7) and 167 to 176 meters (Core 8).
The interval velocity between the bottom and the BSR(0.82 sec at 670 m) is 1.65 km/sec and is quite similar tothe laboratory observations and those obtained at Site 184.

Core

(m)

1
2
3

0-9

Wash
4

Wash
5

Wash

Wash
9
10

Wash
11

Wash
12

Wash
13
14

Wash
15

Wash
16

Wash
17

Wash
2.7
2.6
9.5

Wash
26
27

77.8
Clathrate Corer
Used
45.4

nannofossils, suggesting that the entire diatomaceous partof the sequence once contained nannofossils, but thenannofossils in its lower part were disaggregated bydiagenesis.
Radiolaria and Silicoflagellates
At Site 185, Radiolaria and silicoflagellates were foundin the upper diatomaceous sediments, while the lower
clayey unit, Cores 18 through 27, was barren of thesemicrofossils.
Most of the identifiable radiolarian taxa from this site
are noted in Table 4, Chapter 28. Occurrence of Theocyrtis

174

redondoensis in Core 17 requires some attention. The
species was originally described from sediments of theupper Mohnian Stage of Southern California and reported
subsequently from California by Bandy et al. (1971) andfrom Japan by Nakaseko (1963). This species was also
found in a dredge sample from the continental margin of
the western Bering Sea (collected by D. W. Scholl, USNS
Bartlett, 1970).
Silicoflagellate specimens at Site 185 are more abundant
than at the previous sites and their occurrences are
discussed in Chapter 27 (Ling, this volume).

REFERENCES

Bandy, O. L., Casey, R.E. and Wright, R. C, 1971. Late
Neogene planktonic zonation, magnetic reversals, andradiometric dates, Antarctic to the Tropics. In Antarctic
Oceanology I, Reid, J. L. (Ed.), Am. Geophys. Union,
Antarctic Res. Ser. 15, 1.
Nakaseko, K. 1963. Neogene Cyrtoidea (Radiolaria) fromthe Isozaki Formation in Ibaraki Prefecture, Japan.
Osaka Univ. Sci. Rept. 12(2), 165.

SITE 185

Q

u

u

J

to

CJ3
•a:

n . 2
1
3

111

4

o

-100- 6

LU

GO

7
8 •
• 200- Q

-

1

\
\

O
D-

•

V1

J

i 1.6

\

p

i
i
i
i

i-

11

i
i

-30012
13 •
14

LLJ

2:

LU

-400-

8 •

oc

LU
D.

15

O.

f

•Jri
i}
i
i

-

16

17
-600-

LIMESTONEi

LIMESTONE

!
X
1

!*

XX

'# f
* It
l •
• GAS ^ | 2.0

SILTY CLAY
W. DIATOMS

25
-

26
27

i

„1

18

-700-

f
/
T

°~\

DIATOM OOZE
U. SILT AND
CLAY. ASH
AND PUMICE
IN UPPER• 225 M. -

IC

-500-

VELOCITY

•

UJ
tJ

5

DENSITY* I D C O O (O•― •— •— CM i— CM CV1 CM//////////.
HOLE
TERMINATED

BC

<x.

1
1
1

1
Figure 5. Correlation of seismic reflection profile with physical properties and lithologic column, Site 185.

175

SITE 185
-J
CTv
DENSITY(9m/cc)Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density,

LITHOLOGIC DESCRIPTIONUNIT A
DIATOM OOZE
with variable admixtureof silt and clay
dark olive gray tograyish olive
Numerous layers of:
VITRIC ASH, dark SANDS,
and thin LIMESTONES
to about 250 m,
scattered erratic pebbles

drilling break

LOWER PLIOCENE-

1.0

2.

DENSITY(gm/cc)Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density, *COMPRESSIONALWAVE
VELOCITY(km/sec)
5

2.0

LITHOLOGIC DESCRIPTIONUNIT A(see sheet 1)

•0

2.0

COMPRESSIONALHAVEVELOCITY(km/sec)

3.0 1 .5

2.0

SITE 185

DENSITY(gm/cc)Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density,
DEPTH
LITHOLOGIC DESCRIPTIONLIMESTONE (50 cm t h i c k )UNIT A(see sheet 1)~ y LIMESTONE (40 cm t h i c k )begin transition to
UNIT Bdecreasing diatom
content
DIATOM RICH to
DIATOM BEARINGSILTY CLAY
dark olive gray

COMPRESSIONALWAVE
VELOCITY(km/sec)SITE 185
Sitel85

Hole

Corel

Cored Interval:0-9

LITHOLOGIC DESCRIPTION

2 cm SANDY SILT layer

SANDY SILT

Slide 1-138
25%
lithics, opaques20% clay20% glass
15% feldspar
10% quartz
5% diatoms
2% pyroxene
3% other

XR 1-140
79% amorph.
3% quartz
io% plag.
2% mica
π chlor.
4% mont.
2% augite

ASH

3-4 cm ASH layer
pale yellowish brown (10YR 6/2)

Basic lithology
DIATOMACEOUS SILTY CLAY
dark grayish olive (10Y 2/2)
scattered pods and streaks of:vitric ash and dark sandy silt

Slide 3-75

Tal iuTmm c^rounded erratic
Slide CC
40% diatoms
15% s i l t
45% clay178

15* feld-qtz* owu

SITE 185
WET-BULK DENSITY, gm/cc
1
2
3
POROSITY,*
100
0

SECTION
CM
-0

Grain
Density
2 o

1-

2-

-50
3-

4-

5-

-100
6-

7-125
8-

9-J
—150

185-1-1 185-1-2 185-1-3 185-1-4 185-1-5 185-1-6

179

SITE 185
Sitel85

Hole

Core2

Cored Interval:9-16

LITHOLOGIC DESCRIPTIONVITRIC ASH pod, light brownish gray (1OYR 6/2)
SILT RICH CLAYEY DIATOM OOZE
dark grayish olive (1OY 2/2)
pumice (0.5 - 1.0 cm size)
pods of black (10YR 2/1) SANDY SILT
below 75 cm in sec. 1

LITHOLOGIC DESCRIPTION

CLAY RICH SILTY DIATOM OOZE
olive brown (5Y 4/6)
minor pods of black silt
Slide 1-98
60% diatoms
30% silt
10% clay180

SITE 185

WET-BULK DENSITY, gm/cc
1
2
3

ro

Grain
Density

1 i • i I ' ' ' '100POROSITY,%I

SECTION

CM

I

I

1 1 ^

M
On

l-

-25

2-

-50

3-

4-75

-100

6-

-125

8-

9-J
1-150

185-2-1 185-3-1

181

SITE 185
Site 185

Hole

Core 4

Cored Interval:35-44

LITHOLOGIC DESCRIPTION

DIATOMACEOUS SILTY CLAY
dark grayish olive (10Y 2/2) tograyish olive (10Y 4/2)

sees. 3-5 contain calcareous
pods with some nannofossils
sec. 6 contains small concentrations of spicules
pods of black silt and sand throughout

182

SITE 185
WET-BULK DENSITY, gm/cc
1

2

SECTION
CM
-0

3

M
0 -

1-

r

-25

2-

-50

3-

-75

-100

-125

9-1
-150

' 1

185-4-1 185-4-2 185-4-3 185-4-4 185-4-5 185-4-6

183

SITE 185
Site 185

Hole

Core 5

Cored I n t e r v a l : 6 3 - 7 2

FOSSILCHARACTER

LITHOLOGY

0.5-

1.0—

LITHOLOGIC DESCRIPTION

VOID

100

SILT and CLAY RICH DIATOM OOZE
dark grayish olive (10Y 3/2)
56
70% diatoms
10% silt
20% clayCore
Catcher
Explanatory notes in Chapter 1

184

scattered white concentrations of spicules,
and black pods containing Fe and/or Mn stained material

SITE 185
WET-BULK DENSITY, gm/cc
1

2

I i i i i 1 i i i ' I ' ' ' ' I » 'SECTION

3

CM

M

POROSITY,%
100
0

Grain
Density

I2
M' I i ' ' ' I

On

T

1-

2-

-50

3-

4-

5-

-100

6

7-

-125

8-

9J
-150

185-5-1 185-5-2

185

SITE 185
Sitel85

HoleCore 6

Cored Interval.91-100

LITHOLOGIC DESCRIPTION

DIATOMACEOUS SILTY CLAY
olive gray (5Y 3/2)

pumicepebbleSlide 1-100
45% diatoms
20% silt
35% claydark grayish olive (10Y 3/2), gradational color changes

SANDY ASH, dusky brown (5Y 2/2)
SILT BEARING, CLAY RICH DIATOM OOZE
locally (?) spicule richlight olive gray (5Y 5/2)
Slide 3-94
80% diatoms
5% silt
15% spicules

CLAY and SILT RICH DIATOM OOZE
olive gray (5Y 3/2)

numerous pebbles: some pumice, somerafted debris, up to 2 cm diameterscattered pods of sandy ash similar to thatin section 3
Slide 5-124
60% diatoms
25% silt
15% clay186

SITE 185

WET-BULK DENSITY, gm/cc
1
2
3

SECTIONCM-0

11 i i • i ' ' • ' i » ' ' ' i > ' " ' i

POROSITY,*

Grain
Density
M
On

1-

-25

2-

-50
3-

4-75

5-1

-100

7-

-125

9-J
-150

185-6-1 185-6-2 185-6-3 185-6-4 185-6-5 185-6-6

187

SITE 185

Site 185

Hole

Core 7

Cored Interval.129-138

LITHOLOGIC DESCRIPTION

Slide 1-100
75% diatoms
10% silt
15% clay

100

143

SAND, black

Slide 2-143
30% glass shards
25% lithics, opaques
15% feldspar
10% quartz
3% pyroxene
7% other
10% diatoms

37
PUMICEshell fragments

Basic lithology
SILT and CLAY RICH DIATOM OOZE
dark olive gray (5Y 3/2) tograyish olive (TOY 4/2)

Slide 3-37
70% diatoms
20% silt
10% glass

Slide 5-52
local spicule and nannorich zone

52
pebbleExplanatory notes in Chapter 1

188

SITE 185

WET-BULK DENSITY, gm/cc
1
2
3
j i i i i I i i i > i i » > < i

POROSITY,%
100
0

SECTION

CM

« «i

Grain
Density-a 2 o
3
°

ro

13«

1-

-25

2-

-50

3-

4-75

5-

-100

6-

7-

-125

L-150

185-7-1 185-7-2 185-7-3 185-7-4 185-7-5

189

SITE 185
Hole

Site 185

Core 8

Cored Interval;167-176

FOSSILCHARACTER

LITHOLOGIC DESCRIPTION

LITHOLOGY

0.5-

VOID

1.0130semi-indurated
25
58

119

carbonate pod

Basic lithology
SILT RICH CLAYEY DIATOM OOZEtoCLAY RICH SILTY DIATOM OOZE
dark grayish olive (10Y 3/2) toolive gray (5Y 3/2)

Slide 1-130
60% diatoms
10% silt
30% clay

69

145

«

Slide 4-69
65% diatoms
25% silt
10% clayscattered rafted erratics

NANNOFOSSILIFEROUS LIMESTONE, grayish olive (10Y 4/2)
NANNOFOSSIL RICH SANDY SILT (20% nannos) dusky brown (5YR 2/2)
1-2 cm SANDY SILT layer
dusky brown (5YR 2/2)i—

JK -r-£1ü o.

1-2 cm SAND layer

112

Core
Catcher
Explanatory notes in Chapter 1

190

Slide 5-8
35% sand (glass, feldspar, opaques)
50% silt
15% claySITE 185

WET-BULK DENSITY, gm/cc
1
2
3

SECTIONCM-0

11 i i i I ' ' ' ' i • • • ' i • ' • »I

POROSITY,*
100
0

Grain
Density
"32 o
M
O-i

1-

h-25

2-

-50

3-

-75

-100
6-

7-

-125

8-

-150

185-8-1 185-8-2 185-8-3 185-8-4 185-8-5

191

SITE 185
Site 185

Hole

Cored I n t e r v a l : 2 1 3 - 2 2 2Core 9FOSSILCHARACTER

LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.5-

Semi-indurated
90

1.0--I-

CLAY RICH DIATOM OOZE
dark grayish olive (10Y 3/2)
Slide 1-90
90% diatoms
10% clayCore
CatcherM
Explanatory notes in Chapter 1

192'"(D) Denticula kamtschatica

SITE 185
WET-BULK DENSITY, gm/cc
1

2

SECTION
CM

3

ro
M
O-i

1-

-25

2-

-50

3-

4-75

5-

-100
6-

7-

-125

8-

9-1
L-150

185-9-1

193

SITE 185
Site 185

Hole

CorelO

Cored Interval:222-231

FOSSILCHARACTER

LITHOLOGY

0.5-

LITHOLOGIC DESCRIPTION

VOID
Semi-indurated

1.013375

Explanatory notes in Chapter 1

194

Slide 1-133
55% diatoms
15% silt
30% clay61

SPICULE BEARING, SILT and/or CLAY RICH DIATOM OOZE
dark olive brown (5Y 3/4) to light olive gray (5Y 5/2)
Slide 3-&1
65% diatoms
25% silt
10% sponge spicules

131

SILTY SAND, dusky brown (5YR 2/2), graded fromdiatom ooze at top to silty sand at bottom

92

Core
Catcher

SILT RICH CLAYEY DIATOM OOZE
olive gray (5Y 3/2)

SILT and SPICULE BEARING CLAY RICH DIATOM OOZE
dark olive gray (5Y 3/2)
Slide 4-92
65% diatoms
7% silt
20% clay
8% spiculesSITE 185
WET-BULK DENSITY, gm/cc
1

2

POROSITY,%
100
0

SECTION

3

CM
-0

Grain
Density

1-

-25

2-

-50

3-

4-75

5-

-100

6-

7-

-125

8-

9-1
-150

185-10-1 185-10-2 185-10-3185-10-4

195

SITE 185

ca

00
LU
OC

LU

Q.

-

tagor
•*

kaπ

1
1.0— ._ —

Λ

3

1 s•
+*

CO

*—•

*o

R

s

_

_

r

M
π

Semi-indurated, burrowed

120

1 11

PER I

o

+J

lum

LU
Z
LU
O

J-

VOID

0.5-

C

_« <u
JC
(J

LITHOLOGIC DESCRIPTION

~l~

CO
3

(β

LITHOLOGY

oo

1

O.SAM

zj

O

DRMAT

oo
o
u.

Cored Interval:269-278

1ETERSa?

ECTIOI

Core 11

FOSSILCHARACTER
ND.

Hole

SIL

ZONE

AGE

Site 185. — -•«.

^5

sf

SPICULE BEARING to SPICULE RICH, SILT and CLAY RICH
DIATOM OOZE
dark olive gray (5Y 3/2) to grayish olive (TOY 4/2)

2

z.
—
—
-

CO

Q

^~.

D
Kl

N
R

S

t G
R M
R M

-/— - vSlide 1-120
70% diatoms
10% silt
15% clay
5% spicules

—w— -

,
Core
Catcher ~.

Explanatory notes in Chapter 1
Site 185

Hole

Core 12

Cored Interval .-335-344

FOSSILCHARACTER
LITHOLOGY

0.5—<o

LITHOLOGIC DESCRIPTION

VOID

α>
1.0—

no

Semi-indurated, burrowed

SPICULE and SILT BEARING, CLAY RICH DIATOM OOZE
dark olive gray (5Y 3/2)

104

R M

Core
Catcher

Explanatory notes in Chapter 1

196

scattered concentrations of sponge spicules
Slide 1-110
75% diatoms
5% silt
15% clay
5% spiculesSITE 185

WET-BULK DENSITY, gm/cc
1
2
3
POROSITY.%SECTION

CM
-0

Grain
Density
M
ù-

1-

2-

-50

3-

4-75

-100

-125

9- 1
-150

185-11-1 185-11-2 185-12-1 185-12-2

197

SITE 185
Hole

Sitel85

Core 13

Cored Interval:372-381

FOSSILCHARACTER

LITHOLOGY

0.5-

LITHOLOGIC DESCRIPTION

VOID
Semi-indurated, burrowed

l.OH
SPICULE and SILT BEARING CLAY RICH DIATOM OOZE
dark olive gray (5Y 3/2)
r÷<*>

1.5 cm diam. pod of NANNOFOSSIL OOZECoreCatcher

R M
Explanatory notes in Chapter 1
Site 185

Hole

Corel4

Cored Interval .-381-390

FOSSILCHARACTER
LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.590

SPICULE and SILT BEARING CLAY RICH DIATOM OOZE
dark grayish olive (10Y 3/2)

1.0Semi-induratedCore
Catcher
Explanatory notes in Chapter 1

198

Slide 1-90
75% diatoms
5% silt
15% clay
5% spicules(S) Distephanus speculum var. pentagonus

Core Catcher:
D A G

SITE 185

WET-BULK DENSITY, gm/cc
1
2
3
11 i i i I ' 'SECTIONCM' i ' ' < • i ' ' > ' i

POROSITY,*
100
0

ro

Grain
Density

>

M
O-i

1-

-25

2-

-50

3-

4-75

5-

-100

6-

7-

-125

8-

9-1

L-150

185-13-1 185-13-2 185-14-1

199

SITE 185
Sitel85

Hole
FOSSILCHARACTER

Corelδ

Cored Interval:447-456

LITHOLOGIC DESCRIPTION

LITHOLOGY

0.5 —

VOID

1.0-

SILT and CLAY RICH DIATOM OOZE
olive gray (5Y 3/2)

Core
Catcher
Explanatory notes in Chapter 1
Site 185

Hole
FOSSILCHARACTER

CorelβCored Interval.513-522

LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.5-

jar..::

pod of calcite crystals
100

1.0-

Basic lithology
SILT RICH DIATOMACEOUS CLAY
dark olive gray (5Y 3/2)
semi-indurated
100
1-••l•— ICoreCatcher

Explanatory notes in Chapter 1

200

DIATOM FRAGMENT BEARING LIMESTONE, dark olive gray (5Y 3/2)

-J

Slide 1-100
40% diatoms
10% feldspar
5% quartz
5% opaque
40% clay

Slide 2-100
5% diatom fragments
95% calcite(probably includes someclay)

SITE 185
WET-BULK DENSITY, gm/cc
1

2

11 i i i I i i i

i ' ' • • i » ' ' > I

CM
Grain
Density

POROSITY,*
100
0

I

SECTION

3

ro

2

I i

i T I

I u
i3t

M
On

1-

ú
s
si

2-

-50

WET-BULK DENSITY, gm/cc
1

2

3
Grain
Density-32 o

POROSITY,*
100
0

ü
' I

i

i

i

i I

M
O-i

-100

1-

2-125

-150

185-15-1 185-15-2 185-16-1 185-16-2

201

SITE 185
Site!85

HoleCorel7

Cored Interval:578-587

LITHOLOGIC DESCRIPTION

Semi-indurated

SILT BEARING CLAY RICH DIATOM OOZE
dark olive gray (5Y 3/2)
Slide 2-75
75% diatoms
5% silt
20% clay

LIMESTONE (microspar cemented diatom ooze)

202

SITE 185
WET-BULK DENSITY, gm/cc
1

2

POROSITY,*
100
0

SECTION

3

CM
-0

Grain
Density

1 2«
M
0-i

1-

2-

-50

3-

-75

5-

-100

6-

7-

-125

8-

-150

185-17-1 185-17-2 185-17-3

203

SITE 185
Sitel85

HoleCore 18

Cored I n t e r v a l : 644-653

FOSSILCHARACTER

LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID

Semi-indurated, burrowed
100

1.0—

DIATOMACEOUS SILTY CLAY
dark olive gray (5Y 3/2)
Slide 1-100
40% diatoms
30% silt
30% clay81

several thin (max. 7cm) limestonelayersSlide 2-141
2% diatom fragments
98% calcite (+clay ?)

141
Core
Catcher
Explanatory notes in Chapter 1

LITHO.SAMPLE

LITHOLOGY

DEFORMATION

Cored Interval.652-662

METERS

Core 19

SECTIONPRES.

ABUND.

Hole
FOSSILCHARACTERFOSSIL

ZONE

AGE

Site 185

LITHOLOGIC DESCRIPTION

VOID

b
CSI

D
N
R
S

M
-

Core
Catcher

Explanatory notes in Chapter 1

204

1 1 11 1 1 1 1 1 1 1 11 11

1 1 1 1 1 1 1 1

0.5Semi-indurated

DIATOM BEARING SILTY CLAY
olive gray (5Y 3/2)'—•'-'•'-~•'-~-•

100

SITE 185

WET-BULK DENSITY, gm/cc
1
2
3

SECTIONCM| I M I | I I I I | M M | I I I I |

ro

Grain
Density

POROSITY,%

I2 8

i3t

.u
1-

-25

2-

-50
3-

4WET-BULK DENSITY, gm/cc
1

2

POROSITY,*
100
0

-75

3
Grain
Density
2 u
0-

-100
" I
1-

2-125

3-

L-150

185-18-1 185-18-2 185-19-1 185-19-2

205

SITE 185
Sitel85

Hole
FOSSILCHARACTER

Core 20

Cored Interval.- 662-671

LITHOLOGIC DESCRIPTION

LITHOLOGY

VOID
0.5-

1.0-

SPICULE BEARING, DIATOM RICH SILTY CLAY
olive gray (5Y 3/2)
Slide 3-75, 4-80
25% diatoms
5% spicules
25% silt
45% clay

Sections 1-4 (90 cm) severely disturbed, GASSY
75

i

Sections 4 (90 cm) - cc semi-indurated
Slides 4-92, 4-145

TfmàMm M f _ _ JT

145
10

70

SPICULE BEARING SILT RICH CLAY
dark olive gray (5Y 3/2)

J ! s P]£ u l e s
JJ£ * mSPICULE BEARING DIATOM RICH SILTY CLAY
olive gray (5Y 3/2)
Slides 5-10, 5-70
20% diatoms
2% spicules
25% silt
53% clay

75

Core
Catcher
Explanatory notes in Chapter 1

206

cc

SILT RICH CLAY
dark olive gray (5Y 3/2)

DIATOM BEARING SILT RICH CLAY

Slide 6-75
10% silt
90% clay

Slide CC
5% diatoms
20% silt
75% claySITE 185

WET-BULK DENSITY, gm/cc
1
2
3
POROSITY,*
100
0

SECTION

CM
-0

Grain
Density
M
O-i

l-J

-25

-50

-75
DC
CD
O
O

O

-100

-125

-150

185-20-1 185-20-2 185-20-3185-20-4185-20-5185-20-6

207

SITE 185
Site 185

Hole
FOSSILCHARACTER

Core 21

Cored Interval .-671-680

LITHOLOGY

0.5-

LITHOLOGIC DESCRIPTION

VOID

1.0-

120
Semi-indurated
Interbedded
SILTY CLAY
andDIATOM BEARING SILTY CLAY
dark olive gray (5Y 3/2)

Slide 1-120
layers indistinguishable
without aid of microscope

Jjj* diatoms
3 \J to L 1 d V

75
Slide 3-75
no diatoms

Core
Catcher
Explanatory notes in Chapter 1

208

SITE 185
WET-BULK DENSITY, gm/cc|
2
3
POROSITY,*100
0! i « T Tη

SECTIONCM
Grain
Density

ro
M
On

1-

-25

2-

-50
3-

4-75

5-

6-

-100

7-

-125

8-

9-J

•―150

185-21-1 185-21-2 185-21-3

209

SITE 185

LITHO.SAMPLE

Clathrate corer test
minor recovery - no description available

Cored Interval:683-690

METERSSECTIONPRES.

ABUND.

Core 23

LITHOLOGIC DESCRIPTION

LITHOLOGY

LITHO.SAMPLE |

PRES.

1

Hole
FOSSILCHARACTERFOSSIL

ZONE

AGE

Site 185

LO

o

N
R
S

LITHOLOGY

DEFORMATIONABUND.

M

METERSFOSSIL

ZONE

AGE

R

Cored Interval:680-683

1 I 1 I | I l I I

D

SECTION

Core 22

FOSSILCHARACTER

DEFORMATION |Hole

Sitel85

LITHOLOGIC DESCRIPTION

VOID
0.5-

1

I 14

1.0-

1 1 11 1 I I Il 1lI l I

CSI

D
N
R

ftM

DIATOM BEARING SILTY CLAYtoSILTY CLAY
dark olive gray (5Y 3/2)

diatoms in diatom bearing layers
are largely dissolved
core consists of 1-10 cm semi-indurated
pieces in highly disturbed matrix ofsame materialCore
Catchers

N
R
S

LITHO.SAMPLE

LITHOLOGY

LITHOLOGIC DESCRIPTION

Clathrate corer test
Core
Catcher

Explanatory notes in Chapter 1

210

Cored Interval .-690-691
DEFORMATION |METERS

R M

Core 24
SECTIOND

PRES.

ABUND.

Hole
FOSSILCHARACTERFOSSIL

ZONE

AGE

Site 185

CC recovery only - no description available

SITE 185
WET-BULK DENSITY, gm/cc
1

2

SECTIONCM

3

I i i i • I i i i ' i • • i ' i « > » »I

POROSITY,%
100
0

ro

Grain
Density
M
O-i

1-

-25

2-

-50
3-

4-75

5-

-100
6-i

7-

-125

8-

9-1

•150

mmimmm185-23-1 185-23-2

211

SITE 185
Core25

Cored Interval:691-699

FOSSILCHARACTER
_i
CO

z

CO
LU

o
TIO

LU
CD
<C

LU
Z
o
r g

IX
LU
|—

LU
CO

LU

LITHOLOGY

tx
tx.

o
IX.

SAM

Hole

MAT

Site 185

o

o
|—

LU
Q

I

LITH0L0GIC DESCRIPTION

—J

VOID

1

1

o
M M1 1 M

0.5-

SILTY CLAY
dark olive gray (5Y 3/2)_.. ..

Cf]

2

—
—

locally diatom- and carbonate-bearing
diatoms corroded
calcareous zones lighter colored andassociated with burrows

120

D
N
R
S

_
_

-

Core
Catcher

Slide 2-60
30% silt
70% clay_

XR 2-70
71% amorph.
6% quartz
5% cristo.
7% plag.
3% mica
1% chlor.
3% mont.
3% clinop.
Explanatory notes in Chapter 1

212

Slide 2-120
5% diatoms
20% silt
70% clay
5% carbonate

SITE 185
WET-BULK DENSITY, gm/cc
1

2

Grain
Dens 1ty

POROSITY,%
100
0

I

SECTION3I"3 2 o
I

I

I

I I

M
0-1

-25

-50

3-

4-75

5-

6-

7-

8-

9—150

185-25-1 185-25-2

213

SITE 185
Sitel85

HoleCore 26

Cored Interval:71β-727

FOSSILCHARACTER
LITHOLOGIC DESCRIPTION

LITHOLOGY

VOID
0.51.0-100

LIMESTONE, dark olive gray (5Y 3/2)
burrowed near top

Basic lithology
DIATOM BEARING SILTY CLAY
dark olive gray (5Y 3/2)
diatoms largely corroded
locally burrowed
scattered concentrations of spicules

75

Core
Catcher
Explanatory notes in Chapter 1

214

SITE 185

WET-BULK DENSITY, gm/cc
1
2
3
l' • • ' I ' ' ' ' i 'POROSITY,*
100
0

SECTIONCM• • i • ' « ' i

ro

Grain
Density
2 o

M
O-i

Z-\

1—50

3-4

1-100

7-\

hl25

1—150

185-26-1 185-26-2185-26-3185-26-4185-26-5

215

SITE 185
Sitel85

Hole

Core27

Cored Interval.727-728

LITHOLOGIC DESCRIPTION

Clathrate corer test
core catcher recovery only
SILTY CLAY as in previous core216