8. SITE 189
The Shipboard Scientific Party1

SITE DATA

Date Occupied: 18-22 Aug 71.
Position:
54°02.14'N
170°13.38'E.
Water Depth: 3437 meters.
Penetration: 871 meters.
Number of Holes: One.
Number of Cores: 20.
Total Core Recovered: 74.2 meters.
Acoustic Basement:
Depth: 730 meters
Nature: Sediments, possibly deformed
Velocity: Approximately 2.3 km/sec.
Age of Oldest Sediment: Upper Miocene.
Basement: Upper Miocene or older.
SUMMARY

Site 189 is located on a deeply submerged ridge(3400 m) at the base of the north flank of the Aleutian
Ridge, Bering Sea (Figure 1).
The 871-meter thick sediment and sedimentary rocksequence drilled and cored consists of a Pleistocene to
Pliocene (0-260 m) diatomaceous silty clay to clay-richdiatom ooze, an upper Pliocene (260-370 m) diatom-,carbonate-, and pyrite-bearing silty clay, and an upper
Pliocene to upper Miocene and possibly older (370-871 m)
mudstone sequence that includes sedimentary breccia.
Diatoms show a regular and gradual increase from ~5%at the top to ~40 to 50% at a depth of 260 meters (upper
Pliocene). Discrete beds of ash and sand, pumice pebbles,and erratic sedimentary rock pebbles occur in the Pleistocene section. Part of the Pliocene section (260-360 m) is atransitional facies of silty clay with 5 to 10% diatoms
showing solution effects and pyritization.

1
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.

The mudstone (370-871 m) is mottled and burrowed
with beds dipping up to 30 degrees below 640 meters andshowing tension cracks normal to the bedding.
The prominent acoustic basement beneath Site 189(0.87 sec total reflection time) was determined to be a
deformed 20- to 40-meter thick sequence at 730 meters ofsize-graded sedimentary breccia and calcite-cemented sandstone of probable late Miocene age. Claystone with inclined
bedding also occurs for about 100 meters above the breccia.
This discovery implies that a thick apron or insular rise unit
flanking the base of the Aleutian Ridge was arched after or
during late Miocene time to form the Site 189 ridge. Since
this time the ridge has received a thick covering ofterrigenous-rich hemipelagic deposits. Uplift of the ridge,
beginning shortly after the turbidite layers of sandstone andbreccia were deposited, appears to coincide with a late
Miocene orogenic episode that affected the length of the
Aleutian Ridge.
The terrigenous nature of the sedimentary section drilled
at Site 189 attests to the importance of the adjacent
Aleutian Ridge as a source of detrital debris. However,terrigenous debris from Kamchatka and eastern Siberia canalso reach this area via a Pacific route (Lisitzin, 1969; see
Scholl and Creager, and Fullam et al., this volume. At otherBering Sea sites (e.g., 184, 185, and 188) the late Miocene
and younger deposits are dominated by diatomaceous

168°

172°

Figure 1. Base map showing the location of Site 189.

325

SITE 189

debris. In contrast, except for a short upper Pliocene-lower
Pleistocene section, diatoms at Site 189 are only an
important secondary constituent. In comparison to othersites, the lower diatom content of Site 189 deposits may
also reflect Oceanographic conditions less favorable toplanktonic productivity. Also noted at Site 189 was theuphole appearance of calcareous foraminifera and nannoplankton near the Plio-Pleistocene boundary, a phenomenon found at all other Bering Sea sites that implies a major
downward shift in the carbonate compensation depth in theearly Pleistocene.
BACKGROUND AND OBJECTIVES
Description

A very thick (i.e., 800-1000 m) layer of turbidite
deposits normally abuts the base of the north flank of the
Aleutian Ridge. However, at Site 189 the pelagic (judged
from their acoustic characteristic and depositional geometry) deposits underlying the turbidite section swing
upward and cap a narrow and deeply submerged (3400 m)
ridge trending parallel to and lying at the base of the northflank of the Aleutian Ridge (Figure 1 and 2). Site 189 was
located over the crest of this ridge because here the pelagic
sequence, which appears to rest on a well-defined acoustic
basement, could be sampled to basement without firstpenetrating a thick turbi.dite section.

Objectives

The principal objective in drilling Site 189 was to obtain
information about the lithology and age of the pelagic
sequence and the acoustic basement. This information
should permit a realistic appraisal of (1) the nearby
Aleutian Ridge as a Neogene sediment source, and (2) theformative history of the acoustic basement beneath Site
189 in relation to that of the Paleogene sedimentary andvolcanic rocks that construct the bulk of the ridge.
OPERATIONS
Pre- and Post-drilling Survey

Site 189 is located near the summit of a deeply
submerged northwest-trending ridge at the base of thenorth flank of the Aleutian Ridge. The site occupied isabout 2.7 km northwest of the originally selected location
and, hence, that far from the reference profile obtained by
D. W. Scholl on 26 Aug 70 (Figure 2). The site wasapproached with a ship's heading of 300°T which wasapproximately at a right angle to the heading used in thecollection of the reference profile. Winds and slow computing times for satellite fixes caused the desired site to be
missed. However, the air-gun profile collected during theapproach (Figure 3) revealed enough similar features topermit dropping the beacon on the fly at 2030 hrs 18 Aug
71. The finally accepted position is: 54°02.14'N,

Figure 2. Reference seismic reflection profile, obtained by D. W. Scholl, 26 Aug 70.

326

SITE 189

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sec.
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time,
sec.

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189

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Figure 3. Glomar Challenger air-gun profile obtained on approaching Site 189.

327

SITE 189

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Figure 4. Glomar Challenger air-gun record obtained during post-site survey, Site 189.
170°13.38'E. Because the final site was so far removed
from the selected site, a post-drilling survey was run(Figure 4). A map showing the approach and departure
tracks plus the site location is shown in Figure 5.

Drilling Program

Site 189 was occupied from 2030 hrs 18 Aug 71 (beaconaway) until 0600 hrs 22 Aug 71 with alternating coring andwashing from the sea floor to a subbottom depth of 871
meters. At 730 meters a breccia in a claystone matrix
without diagnostic fossils was encountered. This sedimentary rock correlates well with the expected deepest
reflector, the site target. Six additional cores were collected
downhole before this fact was accepted. Time limitations

328

and the wearing of the bearings on the bit caused
termination of the hole.
Using Matthews Tables, the sonic depth of 1832 fms wascorrected to 3404 meters giving a water depth of 3410
meters and depth from the drill floor of 3420 meters. This
compares with 3447 meters below drill floor established on
the basis of the first core collected containing sediment,
after one water core had been pulled. The 3447 meters
below drill floor, or 3437 meters below sea level, is theaccepted depth for this site.
No drilling difficulties were encountered in drilling theupper 370 meters of silty clay and diatom ooze. Drillingslowed considerably through the claystones from 370 to
871 meters (Figure 6), with the bearing in the drill bit
wearing out completely. A coring summary is given in
Table 1.

SITE 189
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Figure 5. Glomar Challenger track showing approach to and departure from Site 189.

LITHOSTRATIGRAPHY

A single hole at Site 189 penetrated 871 meters of
sediment; the lithologic sequence is shown in the site
summary.
Two lithologic units are recognized. Unit A (0-370 m) isa mixture of diatoms and terrigenous sand and silt, diatoms
showing a regular and gradual increase from ~5% at the top
to ~40 to 50% near the base of the section. Discrete bedsof ash and sand, pumice pebbles, and erratic sedimentaryrock pebbles occur more commonly in the upper (Pleistocene) part of the unit. Cores 5 and 6, toward the bottom of
the unit, are rather gassy. Cores 7 and 8 contain atransitional facies, consisting of silty clays with 5 to 10%
diatoms showing solution effects and pyritization. Faintlenses and bedding become noticeable.
Unit B (370-871 m) is essentially a mottled and burrowed mudstone, with beds dipping up to 30 degrees below
about 640 meters and showing tension cracks perpendicular
to bedding. Between 730 and 755 meters the unit includes
a sedimentary breccia and sandstone which presumably
correlates with an "acoustic basement."
Units A and B are lithostratigraphically equivalent to thesame units defined at Sites 184,185, and 188.
Unit A - 0 to 390 Meters
Unit A, from 0 to 370 meters below bottom, consists ofdark greenish gray diatom-bearing silty clay at the top of
the section grading downward to diatomaceous silty clay

and clay-rich diatom ooze at about 250 meters. The trendwith depth of the terrigenous:diatom ratio is roughly
paralleled by the silt:clay ratio, which decreases fromalmost 1:1 in Core 1 to about 1:4 in the lower sections.
Thin (<5 cm) beds of light gray vitric ash, dark crystal ash,and dark sands and silts occur throughout the unit, but are
more common in the upper (Pleistocene) section, where
pumice and sedimentary rock pebble erratics are also
found. Cores 3 and 4, and especially Cores 5 and 6, were
gassy, characteristic of Unit A at earlier Bering Sea sites.
Sediments of Cores 7 and 8 are olive gray diatom-,carbonate-, and pyrite-bearing silty clays. They are transitional between the true Unit A facies and the Unit B
lithology in that (1) diatoms fall off sharply (<10%) andshow solution effects and pyritization, (2) faint lenses andbedding are apparent, and (3) a few burrows are seen.
Unit B - 370 to 871 Meters

The top of Unit B is just below Core 8 at 370 meters
where the drilling rate slowed abruptly from 4.5 to 1.5
m/min. (Figure 6). The sediment is an olive gray and olive
black mudstone, typically containing 75 to 90% clay, 5 to
20% terrigenous silt (mostly Plagioclase feldspar), and up to
5% pyrite. Microspar (recrystallized nanno ooze?) forms
limestone layers about 10 cm thick; calcite also occurs asveins up to 1 cm thick in disrupted claystone in Core 11.
Discrete layers of volcanic silts and glassy ash (largely
devitrified and altering to clay) occur, as do layers rich indiatoms. These diatoms are often pyritized or recrystallized329

SITE 189
SITE 189

AVE. PENETRATION RATE FOR WASHED INTERVALS

1.0

3.0

2.0

4.0

5.0

6.0

7.0

8.0

TABLE 1
Core Summary - Site 189

METERS/MINUTE

Cored

(m)

(m)

(%)

0-7
7-16

7
9

6.6
CC

94.3
0.0

45-54

9

9.1

101.1

83-92

9

4.7

52.2

147-156

9

6.0

66.7

212-221

9

2.5

27.8

296-305

9

3.6

40.0

362-371

9

1.1

12.2

9
Wash
10
Wash
11

426-435

9

0.8

8.9

537-546

9

3.0

33.3

641-650

9

4.3

47.8

Wash

650-706

12
Wash
13
Wash

706-71590.1
cuttings incenter bit
1.7

18.9

725-733

8

4.3

53.8

14
Wash
15
Wash
16

743-752

9

5.6

62.2

771-780

9

6.5

72.2

799-808

9

4.6

51.1

818-827827-836

9
9

2.2
2.7

24.4
30.0

847-856

9

2.5

27.8

867-871

6

2.4

40.0

174

74.2

42.6

Core
1
2
Wash
3
Wash
4
Wash
5
Wash
6
Wash
7
Wash
8
Wash

Wash
17
18
Wash
19
Wash
20

CORE

16

CORE

17,

CORE

19

CORE

20

CORE

12

CORE

13

18

Figure 6. Subbottom penetration rate, Site 189.

330

Recovered

Cored Interval
Below Bottom(m)as silica. In one limestone bed studied closely, the diatoms
were seen to be completely calcitized. Agglutinatedbenthic foraminifera are common.
Burrows are common in Unit B, (both tiny "fucoid"burrows (~l-mm diameter) and larger burrows (~l-cm
diameter) showing the characteristic en echelon chevronfolds of backfill.
Beginning in Core 10, bedding is characteristically
inclined, and tension cracks (filled with dark gray clay)
arranged normal to the bedding appear. In Core 10, thebedding dips ~IO degrees to the horizontal; from Core 11
to the bottom of the hole the inclination is about 30
degrees. The tension cracks are up to 10 cm deep and areoften sinuously bent, presumably by differential creep(Figure 7). The cracks may end abruptly; Figure 8 shows
cracks abutting against a darker, burrowed clay bed.

SITE 189

Figure 8. Clay-filled tension cracks abutting against adarker, burrowed clay bed (189-12-2, 113-116 cm). Fullcore width.

Figure 7. Tension cracks normal toinclined bedding. The cracks are up to
10 cm deep, are filled with dark clay,
and are often sinuously bent, presumably by differential creep (189-13-2,
115-127cm). Full core width.

A sandstone and sedimentary breccia in a claystonematrix occurs between 730 and 755 meters. Angularvolcanic lithic fragments, clay stone pebbles, pyrite nodules,
and chert pebbles make up the larger grains. Core 14
contains a large ( 6 X 3 X 2 cm) well-rounded gabbro
pebble. Beds of coarse sand and lithic fragments occur
throughout (Figure 9) and in two places are cemented bycalcite spar (Figure 10).
PHYSICAL PROPERTIES

Bulk density, water content, natural gamma radiation,
acoustic velocity, vane shear strength, and residual porewater pressure were measured. The density was measured inthree ways: with the GRAPE system, from shore laboratory
samples, and by the water displacement method. Most of
the samples to a sediment depth of about 300 meters were
disturbed by gas expansion during sampling.

The complete GRAPE bulk densities are shown on thecore summary sheets. As at Site 187, the samples whichwere most affected by gas expansion disturbance yielded
discontinuous GRAPE records. These are shown on thesummary sheets as dashed lines which represent envelopesof the peak GRAPE densities. Mean GRAPE densities foreach section, shore laboratory densities, water displacement
densities, and measured acoustic velocities are shown on thesite summary sheet.
Bulk Density
GRAPE densities were measured from sediment depthsof about 50 to 300 meters. This entire region contained
considerable gas, therefore the measurements may differ
significantly from the in situ densities. Below 300 meters
the sediment did not fill the core liner and was notanalyzed with the GRAPE system. Numerous water displacement densities were obtained for the sediment depth
range 420 to 870 meters.
The densities obtained indicate a sharp increase from
1.45 to 1.65 g/cm3 over the first core, followed by a zone
extending down to 300 meters where the cores were gassy
and the data are scattered. The mean density for this zone
appears to be about 1.5 g/cm3 although this could be inerror because of disturbance. The shore laboratory densities
are probably closer to the in situ condition than are the
GRAPE densities. From a sediment depth of 425 to 550
meters, the density increases from 1.75 to 1.80 g/cm3; andfrom 650 meters to the bottom of the hole, the density
increases gradually and consistently from 2.0 to 2.10
g/cm3. A sharp break evidently occurs between 550 and
650 meters.

331

SITE 189:

Figure 9. Inclined beds of coarse sand andlithic fragments (189-14-3, 142-150 cm).
Full core width.

Figure 10. Inclined graded bed of lithic fragments and sand cemented by calcite spar
(189-14-1, 38-54 cm). Full core width.

Acoustic Velocity
The measured sound velocity increases consistently from
1.5 to 1.75 km/sec over the sediment depth range 0 to 300
meters, and from 2.05 to 2.35 km/sec from 425 meters tothe bottom of the hole. Measurements could not be madebetween 300 and 425 meters because of gas contained by
the sediment. Therefore, it is impossible to determine

332

whether the velocity increases gradually over this region orchanges rapidly at some point.
Summary

The physical property data are not totally conclusivewith regard to differentiating zones at this site. The density

SITE 189

data indicate a break between 550 and 650 meters, but thisis not clearly substantiated by the sonic velocity data.
There is also a significant change in both velocity anddensity over the range 300 to 425 meters, but it is notpossible to determine whether this change occurs rapidly atsome point or gradually over the entire interval.
In general, it appears as if there are three physicalproperty zones: (1) 0 to 300 meters, (2) 425 to 550 meters,and (3) 650 to 870 meters. Each zone is relatively
homogeneous with the density and sonic velocity changing
in the sections between the zones. This zonal distribution
may be in error, however, because of a scarcity of data at
critical points.
PALEONTOLOGY

Stratigraphic control by diatoms and silicoflagellates isgood through the Pleistocene and Pliocene diatomaceous
sediments, although the numbers of these fossils are lessthan at previous sites. Below Core 9, however, identifiable
individuals of the siliceous flora become rare in semilithified sediments, then very rare in Cores 11 and 12. Still
deeper cores at this site have only highly altered, unidentifiable valves of the most resistant types of diatoms.
Evidence for an early Pliocene or upper Miocene age fromdiatoms below Core 10 is tenuous but gains support fromrare sinistral specimens of the foraminiferan Globorotalia(T.) pachyderma in Core 13.
Calcareous foraminifera and nannofossils disappear
downhole near the Pliocene-Pleistocene boundary, as has
been the case at all previous Bering Sea sites. This suggeststhat the carbonate compensation depth stood at somedepth less than 2000 meters in the Pliocene and thenintermittently fell below 2700 meters in the Pleistocene.
Dominantly arenaceous faunas at deeper levels at this site
suggest that the carbonate compensation depth was also
shallow in the upper Miocene.
Sediment layers penetrated toward the bottom of thehole at Site 189 include sandstone and conglomerateintercalated in mudstone; they bear tension cracks and havea marked dip relative to the long axis of the cores. Thesefeatures suggest tectonic deformation, therefore evidence
from the fossil assemblages for important vertical displacement of the sea floor at Site 189 has been sought. Benthic
foraminiferal assemblages indicate that the deformed sediment layers were deposited at paleodepths in the middle
bathyal to abyssal range and also show that Pleistocene
sediments were deposited at depths comparable to that at
which the site presently occurs. There is no positive
evidence of paleobathymetry for Pliocene sediments
because foraminifera are absent, and diatoms, the mostabundant fossils, are undiagnostic of bathymetry below
shelf depths. However, absence of calcareous fossils, which
are common on the upper and middle parts of thecontinental slope of the Bering Sea today, in some places todepths of more than 3000 meters (Saidova, 1961), may be
negative evidence for considerable Pliocene depth of deposition. This assumes that calcareous tests are absent becauseof solution or nonproduction below the carbonate compensation depth and that the carbonate compensation depth
did not migrate to depths much above 2000 meters in the
Pliocene. Arenaceous tests may be absent from Pliocene

sediments because of unfavorable conditions for Eggerellasp., the only species that is consistently preserved inoverlying sediments. There is, therefore, no paleontologicalevidence for vertical displacement of the sea floor. However, vertical movements raising the sea floor to depths ofabout 2000 meters could probably go undetected from
paleontological evidence.
Foraminifera

Good planktonic and calcareous benthic assemblages
alternate with sparse assemblages through Core 4. Foraminifera are rare in Core 5, and in Cores 6 through 10 noforaminifera were found in the core catcher samples. From
Core 11 to Core 20, the bottom of the hole, a faunaconsisting almost entirely of species with agglutinated walls
is present. Specimens of agglutinating foraminifera areconspicuous as white spots on partially dried, cut surfacesof these lower cores. The level at which foraminifera
disappear down the hole (between Cores 5 and 6) corresponds to the Pleistocene-Pliocene boundary as determinedfrom study of diatoms. As at Site 188 a noncalcareous
Eggerella becomes the dominant benthic form near the
Pleistocene-Pliocene boundary.
Foraminifera from the lower part of Site 189 (principally from Cores 13 and 16) include Cyclammina cancellata, C. pusilla, C. trullisata, Glomospira charoides,
Bathy siphon
rusticum?, Martinottiella communis,
Cribrostomoides subglososus, Rhizammina sp., andAmmodiscus sp.. Most of these species are unusually large
compared to other foraminifera; specimens larger than
1 mm are common. Many specimens are flattened along
bedding planes and almost all arenaceous individuals are, tosome degree, distorted. Rare calcareous forms in Core 13
include Pullenia bulloides, Robulus sp., and three sinistrally
coiled specimens of Globigerina pachyderma.
Coiling of G. pachyderma follows the pattern establishedat Site 188. That is, dextral tests appear downcore insignificant numbers in the middle Pleistocene and become
dominant in the lower Pleistocene. The three sinistral
specimens of G. pachyderma in Core 13, occurring below
Pliocene diatom floras, suggest late Miocene age becauselate Miocene populations of this species are sinistral, while
known middle Miocene and early Pliocene populations are
dominantly dextral.
The dominantly agglutinated faunas of the lower part ofthis site suggest a middle bathyal to abyssal habitat below
the local carbonate compensation depth at the time, whichis unknown. The dominantly arenaceous, lowest Pleistocene
benthic fauna at this site, similar to that of the highest
Pliocene of Site 188, suggests that the carbonate compensation depth remained above the present water depths ofthese sites through the barren zone of the upper Miocene
and Pliocene and then fell to deeper levels near the
Pliocene-Pleistocene boundary.
Calcareous Nannoflora

Rare nannofossils occur in the Pleistocene section (Cores
1 through 5), but not below. This parallels the stratigraphic
distribution of nannofossils at other sites in the Bering Sea.

333

SITE 189

Radiolaria and Silicoflagellates
Sediments of Site 189 contain generally rather poor
assemblages of radiolarians and silicoflagellates in paucityof specimens as well as low species diversity. This isparticularly true for the sediments below Core 6, Miocene
interval, where these microfossils are essentially absent.
Radiolarians in Core 1 are a typical Bering Sea (surface
sediments) fauna. As shown in Table 8, Chapter 28, samplesof Core 3 yield Eucyrtidium(?) tumidulum and Stylacontarium acquilonium, but without Axoprunum angelinum,suggesting that the sample is still in the late Pleistocene
Eucyrtidium tumidulum zone of Hays (1970). Radiolarians
were absent below the level of Core 6.
Only a few species of silicoflagellates were recovered(Table 8, Chapter 27), but early Pliocene or Miocene index
forms were completely absent from this site.
Diatoms
Diatoms were less abundant in sediments throughout thesite than those from other previous Bering Sea sites.
Stratigraphic occurrence of this microfossil group is shownin Table 7, Chapter 30. The age of Cores 11 and 12 could
still be considered as late Pliocene based on the similarity of
microfloral composition with the unit immediately above.
CORRELATION BETWEEN REFLECTION PROFILEAND STRATIGRAPHIC COLUMN

The reflection profile obtained by D.W. Scholl, 1970,
which was used for selecting Site 189 is shown in Figure 11
along with the stratigraphic column and physical properties.
The track for this profile is 028°T (to the right). Although
the total sediment thickness appears to be 0.83 sec on thisprofile, the actual position of Site 189 was about 3 km westof this profile; and the Glomar Challenger's records show atotal sediment thickness of 0.87 sec.
The upper 0.40 sec of well-stratified reflectors correlatewith Unit A. The light zone between 0.40-0.50 sec appears
to correlate to less diatomaceous silty clay. At 0.50 sec astrong reflector is present which correlates well with the
top of the mudstone (Unit B) at 370 meters. Hard drilling
was also first encountered there. Velocities in this upper
370 meters were near 1.6 km/sec according to thelaboratory measurements and were 1.48 km/sec according
to the travel-time method (370 m by 0.50 sec).
The dark reflector at 0.50 and the terminal reflector at
0.87 sec appear to mark the top of the mudstone (Unit B)
at 370 meters and the sedimentary breccia at 730 meters.

334

The velocities within Unit B also present a slightproblem. The few laboratory measurements made in thisinterval yielded values between 2.0 and 2.4 km/sec while a
travel-time estimate (370-730 m and 0.50-0.87 sec) suggests
a velocity of 1.95 km/sec. The discrepancy between thesetwo values may be due to the fact that this unit, in which
the drilling was alternately hard and soft, probably
recovered the hardest and most lithified strata whilewashing out the softer layers. Likewise, laboratory measurements are sometimes difficult to obtain on the softer andmore disturbed sections, again biasing toward high values.
Before drilling Site 189, it had been assumed that thestrong terminal reflector at 0.87 sec was an "igneous"basement near 720 meters depth (using 1.65 km/sec for an
average velocity, which was typical of our previous Bering
Sea sites). However, a sedimentary breccia was encountered
between 730 and 755 meters with another mudstone
below. Because of uncertainty in the velocities, drilling wascontinued to 870 meters in search of an igneous basement.
Because the 0.87-sec reflector would require an averagevelocity greater than 2.0 km/sec to be deeper than 870
meters, it was concluded that the sedimentary breccia musthave been the 0.87-sec reflector and the hole was terminated. Furthermore, because the densities and velocities in
Unit B are all near 2.0 g/cc and 2.3 km/sec, the highreflectivity of the sedimentary breccia must be related to itscoarse texture. The 30-degree inclined bedding observed
below 730 meters also suggests that the lower part of Unit
B is deformed sediments, accounting for the absence ofcoherent reflections below the 0.87-sec reflector.
In summary, the well-defined terminal reflector or"acoustic basement" at Site 189 is composed of sedimentary breccia underlain by deformed sediments rather
than the typical igneous basement expected. Site 187 on
the Aleutian Terrace had a similar terminal reflector
underlain by deformed terrace sediments.
REFERENCES
Hays, J.D., 1970. The stratigraphy and evolutionary trendsof Radiolaria in North Pacific deep-sea sediments. Geol.
Soc. Am. Mem. 126. 185.
Lisitzin, A.P., 1969. Recent sedimentation in the Bering
Sea: Nat. Sci. Foundation, Washington, D.C., Israel
Program for Sci. Translations, 614 p.
Saidova, H.M., 1961. Ekologiia foraminifer i paleogeografiia
dal'nevostochnykh movei SSSR; severo-zapadnoi chast;
Tikhogo Okeana. Akad. Nauk SSSR, Inst. Okeanologii.
182 p.

SITE 189se-

cc cc 1— —'o ct_5 o _i
2 I

LU
Q

3

QI—
LU

DENSITY

LU

•

i»
*

LU
•zr
C_3

4

DIATOM
SILTY
CLAY

-

5

o
to
LU

I
Q.

t

A

M

CMCM

•H.. 'LU. o

VELOCITY^• oo

C\J ^ • I D Q) O io oi— .— ^ - r — C M , _ C M

tπ
<:

oò

200

00

6

•

•i

•

1

o
-o - 7

•i

8

•I

z:
o

SILTY CLAY
BEARING
DIATOMS,
00 O
CARBONATE,

t

AND

|

PYRITE

- o -

•

HARD
DRILLING

LU

IOCE

<d•

9

•

•

•

•

o
•o LO

B

MUDSTONEI0 •o• IoO --

12 •13 • I
14
15 •

o

• o
00

-

SEbrBRECIA

i

z

111

•

//////////
HOLE TERMiNATYD

-

* 3b

-?-

16

18 M i19 M i
20

? β

2.

-

β

BAR

o
' O "

no.

1 1• i

•

i
i

06

a
«
i

•

•

I

i

Figure 11. Correlation of the seismic reflection record with physical properties and the lithologic column, Site 189.

335

SITE 189
ON
. DENSITY(gm/cc)Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density, A
LITHOLOGIC DESCRIPTION

(m)

2.

COMPRESSIONALWAVE
VELOCITY(km/sec)
5

2.0

DEPTH
(m)

DENSITY(gm/cc)Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density,
LITHOLOGIC DESCRIPTION

y •
y •
y •

Facies may be t r a n s i t i o n a l , asilty clay with 5-10% diatoms,
these showing solution effects
and pyritization.

Faint lenses
and bedding, a
few burrows.

y,
UNIT ASILTY CLAY to
DIATOMACEOUS SILTY
CLAY, dark greenish gray,with diatom content
increasing downward. Local
erratics, ash layer, volcanic
sand layers.

sharp breakin drilling rate

UNIT B
MUDSTONE,o l i v e gray and o l i v e black,
local limestone l a y e r s ,volcanic s i l t and sand, ashburrows common

.0

2.0

COMPRESSIONALWAVE
VELOCITY(km/sec)SITE 189

SITE 189
DENSITY(gm/cc)COMPRESSIONALWAVE
VELOCITY(km/sec)

Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density,

LITHOLOGIC DESCRIPTION

.0

2.0

:

5

2.0

DENSITY(gm/cc)Mean GRAPE Density, +Shore Laboratory Density, x
Water Displacement Density,

DEPTH
LITHOLOGIC DESCRIPTIONUNIT B(see sheet 2)

Bedding at •v.10" to h o r i z o n t a l ,tension cracks normal to
bedding planes.

"Z
Sandstone andsedimentary breccia, bedding
at 30° to horizontal.
U>

u>

-J

UNIT B(see sheet 2)

COMPRESSIONALWAVE
VELOCITY(km/sec)
2.0

SITE 189
Site 189

Hole
FOSSILCHARACTER

Core 1

Cored Interval:0-7

LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.5-

1.0-

Basic lithology, sections 1, 2, 3
SILTY CLAY
very dark gray (5Y 3/1)
Slide 1-100
55% clay, 45% silt
Slide 2-130
55% clay, 40% silt, 3% diatoms

100

130

DIATOM BEARING SILTY CLAY
112
120

SILT and CLAY RICH DIATOM OOZE, dark grayish olive (10Y 3/2)
VITRIC ASH dark grayish brown (2.5Y 4/2)
disturbed and mixed DIATOM OOZE andSILTY CLAY with pods of VITRIC ASH
greenish gray (5GY 6/1)

85
122

104?-VOID
145
Core
CatcherR

M

Explanatory notes in Chapter 1

338

Basic lithology, sections 4, 5
DIATOM BEARING SILTY CLAY
dark greenish gray (5GY 4/1)
contains disturbed pods and steaks of:
SILT RICH DIATOM OOZESILTY CLAY, greenish black (5GY 2/1)
DIATOM RICH SILTY CLAY
and VITRIC ASH light olive gray (5Y 6/1)

Slide 4-85
50% clay
45% silt
5% diatoms

SITE 189

WET-BULK DENSITY, gm/cc
1
2
3
11

i i i i i i i i i i i i i i i i i

POROSITY,*
100
0

SECTION
CM
-0

11

Grain
Density
M
0-

1-

-25

2-

-50
3-

4-75

-100

6-

-125

9- 1
-150

189-1-1 189-1-2 189-1-3 189-1-4 189-1-5

339

SITE 189

s

R
R

M
M

LITHOLOGIC DESCRIPTION

core catcher sample contained
2 pebbles, both 1-2 cm diameter:

Core
Catcher

Explanatory notes in Chapter 1

340

LITHOLOGY

LITHO.SAMPLE

G

Cored Interval;7-16
DEFORMATIONFMETERSDNRCore 2
SECTIONPRES.

*

ABUND.

ZONE

*

Hole
FOSSILCHARACTERFOSSIL

AGE

Sitel891) hornblende diorite (angular)2) sandstone1(vole, source ?) (subrounded)* ,UPXPER PLEISTOCENE(D) Denticula seminae

SITE 189
Site 189

Hole
FOSSILCHARACTER

Core 3

Cored Interval;45-54

LITHOLOGY

LITHOLOGIC DESCRIPTION

18
PUMICE PEBBLES
0.575
1.0-

+v/•

Basic lithology slides
3-75
5-75
1-75
65% clay
70% clay
55% clay
20% silt
30% quartz, feldspar 30% silt
5% diatoms
10% diatoms
10% diatoms
5% other

60

CRYSTAL ASH, olive black

10

CRYSTAL ASH, olive black (5Y 2/1)

75
80

2/1)

Basic lithology
DIATOM BEARING to DIATOM RICH SILTY CLAY
dark greenish gray (5GY 4/1)

111
section 1 contains pods of light colored
VITRIC ASH (95% glass, 5% feldspar)ç^rr._~._~jv/•sections 2-6 contain pods, streaks andthinbeds of dark colored CRYSTAL ASH
Slide 3-10
Slide 5-125
30% glass
40% glass
25% lith. frags. & opaque 35% feldspar
20% feldspar
20% lith. frags.
20% clay
2% pyroxene
2% pyroxene

75
Gassy core

SILT and CLAY RICH DIATOM OOZE
dark greenish gray (5GY 4/1)
erratic pebble is METASEDIMENTCore
CatcherR

M

Explanatory notes in Chapter 1

342

SITE 189
WET-BULK DENSITY, gm/cc
1

2

POROSITY,*
100
0

SECTION
CM
-0

3
Grain
Density
-32 o

1,1

M

On

1-

-25

2-

-50
3-

4-75

-100

6-

7-

-125

8-

9- 1

-150 • • ü

•l•i

•I••S

189-3-1 189-3-2 189-3-3 189-3-4 189-3-5 189-3-6

343

SITE 189
Site 189

Hole

Core 4

Cored Interval; 83-92

LITHOLOGIC DESCRIPTION

140

75

DIATOM BEARING SILTY CLAY dark greenish gray (5G 3/1)
70% clay, 20% silt, 10% diatoms
Basic lithology
DIATOMACEOUS SILTY CLAY
dark greenish gray (5G 4/1)

transitional downwards to
DIATOM BEARING SILTY CLAY
dark greenish gray (5G 4/1)
75

129
10

SILT RICH, CLAYEY DIATOM OOZE
olive gray (5Y 4/1)
SANDY SILT
dusky yellowish brown(10YR 2/2)
major minerals: pyroxene and Plagioclase
very well sorted

80

Slide 2-75
50% clay
20% feldspar. quartz
2% pyroxene
2% opaque
25% diatoms
Explanatory notes in Chapter 1

344

LOWER PLEISTOCENE(D) Actinocyclus oculatus

Slide 3-75
60% clay
35% silt (mostly feldspar)
3% diatoms

SITE 189

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

SECTION
CM
-0

Grain
Density
32 o

M

H
O-i

1-

-25

2-

-50
3H

4-75

5-

-100
6-1

7-

-125

8-

-150

189-4-1 189-4-2 189-4-3 189-4-4

345

SITE 189
Site 189

Hole

Core 5

Cored Interval:147-156

LITHOLOGIC DESCRIPTION

Basic lithology
DIATOM RICH SILTY CLAY
dark greenish gray (5GY 4/1)
60 - 70% clay
10 - 20% feldspar
15 - 25% diatoms~2% opaques and pyroxene

VITRIC ASH olive gray (5Y 4/1)

SILT BEARING DIATOM RICH CLAY layers
olive gray - greenish black (5Y 4/1 - 5GY 3/1)
80% clay5 - 10% silt
10 - 15% diatoms

346

SITE 189

WET-BULK DENSITY, gm/cc
1
2
3

SECTIONCM

I i i i ' I ' ' ' ' i i ' ' ' i ' ' i ' i
Grain
POROSITY,*
Density100
0-B 2 oro3 <->*3 **3 „ ε-3 3 σ>

M

1-

-25

2-

-50
3-

4-75

5-

6-

-100

7-

-125

L-150

189-5-1 189-5-2 189-5-3 189-5-4

347

SITE 189

Site 189

Hole

Core 6

Cored I n t e r v a l : 212-221

FOSSILCHARACTER

LITHOLOGY

LITHOLOGIC DESCRIPTION

0.5
87

DIATOMACEOUS SILTY CLAY
dark grayish green (5GY 4/1)
40% clay, 20% silt, 40% diatoms
XR 2-20
70% amorph.
10% quartz
7%plag.
6% mica
1% chlor.
5% mont.
1% clinop.

1.0—

o £

Core Catcher
D C G
PF _
BF N

R

R M

S

R M

SILT and CLAY RICH DIATOM OOZE
dark greenish gray (5G 4/1)
65% diatoms, 20% clay, 15% silt
136
Core
Catcher

CLAYEY SILT
olive black (5Y 3/1)
60% feldspar (& qtz ? ) , 10% opaque.

pyroxene, 25% clay

5-10 cm voids throughout core due to gas expansion
Explanatory notes in Chapter 1

348

SITE 189
WET-BULK DENSITY, gm/cc
1

2

SECTION3

CM

I i i < > I ' ' ' ' i ' ' « ' i ' ' i ' i

POROSITY,%
100
0

ro

Grain
Density
2
3

l-

-25

2-

-50

3-

-75

-100

6-

7-

-125

•-150

law

189-6-1 189-6-2

349

SITE 189
Site 189

Core 7

Hole

Cored Interval: 296-305

FOSSILCHARACTER
LITHOLOGIC DESCRIPTION

LITHOLOGY

VOID

0.5-

\.0-\

-115
£Z

3

60
o .;f

SILT and DIATOM RICH CLAY
dark greenish gray (5GY 3/1)
60 - 80% clay
10 - 15% silt
10 - 15% diatoms
locally up to 15% carbonate

35
80

DIATOM RICH SILTY CLAY
olive gray (5Y 3/2)
60% clay
30% feldspar (& qtz ?)10% diatoms
locally pyrite bearing

Core
Catcher

XR 2-1072% amorph.
9% quartz
9% plag.
3% mica
2% chlor.
4% mont.
3% clinop.
Core Catcher:
D C M
PF BF N - R M

some burrowing in lower part

1
1.0-

Core
Catcher~

i!i;i;i!i!i!i!i!i!i!i!

0.5—

LITHO.SAMPLE

DEFORMATION

LITHOLOGIC DESCRIPTIONVOID
I I I l l l l l l l !
i l l1 1 1 1 E l I I
I1 I1 1 1 1 11 1 1 1 11 1 1 I 1 I 1 1 1

PRES.

ABUND.

ZONE(D) Thalassiosira zabelinae(S) Ammodochium rectangulare

FOSSILAGE
UPPER PLIOCENE

LITHOLOGY-

Explanatory notes in Chapter 1

350

Cored I n t e r v a l : 362-371

METERS

Core 8FOSSILCHARACTER

i; i ; i j i; i; i; i; i; i; i; i;Hole

SECTION

Site 189

no

SILT RICH CLAYo l i v e gray (5Y 4/1)
85% clay
15% s i l t~1% diatoms
f a i n t bedding

XR 1-110
64% amorph.
12% quartz
8% plag.
11% mica
2% chlor
2% mont.
TR clinop.
1% amphib.

Core Catcher:
D C M
PF BF N
- R
- _
S R M

SITE 189
WET-BULK DENSITY, gm/cc
1

2

3| i i i M ' ' ' ' I' ' ' I " ' i i I

l

l

I

ro

Grain
Density

POROSITY,*
100
0

i

SECTION
CM

1

I

I

T

|

M
O-i

1-

-25

2-

-50
3-

4-75

5-

-100
6-

7-

-125

8-

9-1
•—150

189-7-1 189-7-2 189-7-3 189-8-1

351

SITE 189

LITHO.SAMPLE |LITHOLOGY

DEFORMATIONMETERSSECTIONPRES.

FOSSILZONE(S) Ammodochium rectangulare

zabelinae

Cored Interval: 426-435

LITHOLOGIC DESCRIPTION

VOID

1
D
R
S

C M

O

(D) Thalassiosira

AGE

Core 9LO

UPPER PLIOCENEABUND.

Hole
FOSSILCHARACTER

Site 189

r_-_-_-_—

1
1
1 125
|

Core
Catcherdiatom fragment bearing SILT RICH CLAY
dark greenish gray (5GY 4/1)
Slide 1-125
75% clay
20% silt (qtz. feldspar etc.)
5% diatom fragments

XR 1-120
Core Catcher:
81% amorph. D R M
5% quartz
PF 5% plag.
BF 2% micaN - 4% chlor.
R R P
3% mont.
S R P
1% clinop.

slight mottling and burrowing

Site 189

Hole

Core 10

Cored Interval: 537-546

FOSSILCHARACTER

LITHOLOGY

LITHOLOGIC DESCRIPTION

CLAY
olive black (5Y 2/1)

0.5—
91
105

1.0-

135

XR 1-60

D
PF
BF
N
R
S

SILT
Basic lithology
SILTY CLAY
dark gray (N3) to olive black (5Y 2/1)

o .^

VOID

Core
Catcher

locally calcareous (up to 85% carbonate)in thin beds
fine burrowing throughout
bedding may be inclined about 10c
in lower part of coresection is SILTY CLAY with 1% or lessof partially dissolved diatoms

Explanatory notes in Chapter 1

352

Core Catcher

65% amorph.
13% quartz
5%plag.
14% mica
3% chlor.
1% mont.

F
_
_
_
_
R

M
_
_
M

SITE 189

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

SECTION

CM
-0

Grain
Density
I2 o
M
On

1-

-25

2-

-50

-75

5-

-100

6-

7-

-125

-150

189-9-1 189-10-1 189-10-2

353

SITE 189
S i t e 189

Hole
FOSSILCHARACTER

Core 11

Cored Interval.-641-650

LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.5-

38
67
zone of vertical fractures filled withdark gray (N3) CLAY

1.0118

25

120
130

zone of calcite veins in the basic lithology
clay filled fractures
Basic lithology
SILT BEARING to SILT RICH
CLAYSTONE
olive gray (5Y 2/1 - 4/1)
VITRIC ASH
beds 1 cm - 3 cm thick, inclined up to 25°
burrows
scattered small sponge ? remains

75

137?
Core
Catcher
Explanatory notes in Chapter 1

354

XR 3-30, 3-80, 3-13059%
47% 58% amorph.
20%
33% 28% quartz
4%8%
6% plag.
5%
4%2% mica2%1%
λ% chlor.
10%3% 3% mont.
2%
clinop.
1%
1% pyrite

SITE 189
WET-BULK DENSITY, gm/cc

j

2

3

SECTION

CM

ro

Grain
Density

POROSITY,*100
0.- ^ • • n i

M
I

i

'

i

i ]

O-i

1-

-25

2-

-50

3-

4-75

5-

-100

7-1
-125

L-150

189-11-1 189-11-2 189-11-3

355

SITE 189
Site 189

Hole
FOSSILCHARACTER

Core 12

Cored Interval: 706-715

LITHOLOGIC DESCRIPTION

LITHOLOGYLO

O

XR 2-50, 2-80
44%38% amorph.
41%
7% quartz
7%19% plag.
4%3% mica2%
1% chlor.
2%
26% mont.
5% clinop.
1% pyrite

VOID
O

TO"

22

LIMESTONE, very light gray (N8), upper contact gradationalCore Catcher:Core
CatcherD

R M

Basic lithology
SILT RICH CLAYSTONE
olive gray - olive black (5Y 4/1 - 2/1)
90% clay, 10% silt
sec. 2, ~40 cm and ~67 cm: thindiatom rich layers
sec. 2, ~80 cm: devitrified ash
la er

y

sec. 2, 30, 46, 110, 122 cm: zones oftyRtensional, clay-filled fractures
oriented generally normal to bedding

burrows
bedding inclined up to 30°
Explanatory notes in Chapter 1

356

SITE 189

WET-BULK DENSITY, gm/cc
1
2
3

SECTIONCM

11 i i i I i i i i i > < ' > i ' ' « ' i

POROSITY,*
100
0

rθ

Grain
Density
-32 o

M
O-i

1-

-25

2-

-50

4-75

6-

-100

7-

-125
8-

9-1

1-150

189-12-1 189-12-2

357

SITE 189
Site 189

Hole
FOSSILCHARACTER

Core 13

Cored Interval; 725-733

LITH0L0GIC DESCRIPTION

LITHOLOGY•b

SILTSTONE

0.5SANDY SILTSTONE, dark greenish gray (5G 4/1)
40%
LIMESTONE
9 l a s s ' 30% Py r o x e n e » 30 °^ feldspar
1.0Basic lithology
SILT BEARING to SILT RICH CLAY
olive gray 5Y 3/2
average composition: 90% clay, 10% silt

bedding inclined about 30°

94

SAND
40

XR 3-50
69% amorph.
17% quartz
7% plag.
3% mica
2% chlor.
mont.
pyri te

CLAY, greenish gray (5G 6/1)
SAND, very coarse and CLAY PEBBLE CONGLOMERATE
olive gray (5Y 3/2)
pyrite nodules
coarse SAND and CLAY PEBBLE CONGLOMERATE

Explanatory notes in Chapter 1

358

SITE 189

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

SECTION
CM

ro

Grain
Density
I2 «
M
ù-i

1-

-25

2-

-50
3-

-75

5-

-100
6-

7-

-125

8-

^

1—150

189-13-1 189-13-2 189-13-3

359

SITE 189
S i t e 189

HoleCore 14

Cored I n t e r v a l : 743-752

FOSSILCHARACTER

LITHOLOGY

LITHOLOGIC DESCRIPTIONVOIDGABBRO pebble (5 x 6 x 3 cm) at top of core
coarse LITHIC FRAGMENT SANDSTONE, calcite cemented
with 1-2 cm thick interbeds of SHALE PEBBLE CONGLOMERATE

0.5—.o- "-----"-I-!-:

•

•

'

'

Basic lithology
SILT BEARING CLAYSTONE
olive gray (5Y 3/2 - 5Y 4/1)
85% clay, 5-10% silt, 5-10% pyritized diatoms
bedding inclined 30%
irregular, lensy bedding, vertical tensional fractures
82,84

LIMEST0NE

85% calcite, 10% clay,

pyritized diatoms

coarse SAND laminae in CLAY matrix
VOLCANIC PEBBLE
95
coarse SAND and fine GRAVEL in clay matrix

coarse SAND
XR 3-140, 4-80, 4-150
calcite cemented SANDCoreCatcher
Explanatory notes in Chapter 1

360

48%

47%

24%
17%
6%
5%

12%
20%
5%
16%

44%
amorph.
19% calci te
1% quartz
21%
plag.
2%
mica
chlorite
4%
3% clinop.

SITE 189
WET-BULK DENSITY, gm/cc
1

2

POROSITY,*
100
0

SECTION

3

CM

roGrai nDensity

Ti

I;

"1

M
0-1

f

•

1
H

H
K-50

hi
I 1

i• • ' :

3-1

H100

6H

1

fi
;

1—125

Sr.

J

‰ 1

9-J

1—150

189-14-1 189-14-2 189-14-3 189-14-4

361

SITE 189
Site 189

Hole

Core 15

Cored Interval:771-780

FOSSILCHARACTER
LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.51.0Basic lithology
SILT BEARING CLAYSTONE
olive gray to olive black(5Y 2/1 - 4/1)
bedding inclined about 30°
burrows
vertical tension cracks filled withclay and deformed (?) apparently
by subsequent flowage.

clay
feldspar , quartz
pyri te
glass
l

i

i

SILT and PYRITE BEARING LIMESTONE
upper contact gradational to basic lithology
XR 1-90, 2-120
36%
68%
amorph.
37%
17% quartz
12%
5%
plag.
10%
6%
mica
4%
2%
chlor.
1%
1% mont.
1%
λ%pyriteVOID

75
Core Catcher:
D - -

Core
Catcher
Explanatory notes in Chapter 1

362

N - R - S - PF BF -

SITE 189

WET-BULK DENSITY, gm/cc|
2
3

SECTION

CM

ro

Grain
Density

POROSITY,*
100
r i i i

π

M
O-i

1-

-25

2-

-50
3-

4-75

6-

-100

7-

-125
8-

9-1
•―150

189-15-1 189-15-2 189-15-3 189-15-4 189-15-5

363

SITE 189
Site 189

Hole

Core 16

Cored Interval:799-808

FOSSILCHARACTER

LITHOLOGY

LITHOLOGIC DESCRIPTION

VOID
0.5-Basic lithology
SILT BEARING CLAYSTONE
olive gray - olive black (5Y 4/1 - 2/1)
90% clay, 10% silt
toward bottom of core becomes:

1.0-

SILT RICH CLAYSTONE
olive gray (5Y 3/2)
75

LIMESTONE 85% clay, 15% silt

no130-~-i-l-l-i-i-i
-O

24
40
73

VOID
Core
Catcher
Explanatory notes in Chapter 1

364

bedding lensy, laminae 1 cm - 4 cm thick;light and dark color bands 3-4 cm thick; backfilled burrows; bedding inclined up to 40°
diatom frag.
or pollen (?)
rich layer
devitrified VITRIC ASH
XR 3-80
74% amorph.
3% quartz
9% p l a g .
15% mont.

SITE 189
WET-BULK DENSITY, gm/cc
1

2

j i i i i i ' ' ' ' i • > ' ' i »POROSITY,*
100
0

SECTION

3

CM

' i

J

Grain
Density

I2 «

j•

1-

II

-25

2-

-50

3-

4-75

5-

-100

6-

7-

-125

8-

9-1

«-150

189-16-1 189-16-2 189-16-3

365

SITE 189
Core 17

0.5-

LITHO.SAMPLE |LITHOLOGY

DEFORMATION |Cored Interval:818-827

METERSSECTIONPRES.

ABUND.

Hole
FOSSILCHARACTERFOSSIL

ZONE

AGE

Site 189

LITHOLOGIC DESCRIPTION

VOID

1
-120
1 1 1 1 1 1 1 1 1 1 1 1 1 1

2

D
N
R
S

bedding inclined 30°
burrows
XR 2-10064% amorph.
22% quartz
6% plag.
6% mica
λ% chlor.

Core
Catcher—

LITHO.SAMPLE

LITHOLOGY

DEFORMATION

Cored Interval:827-836

METERS

Core 18

SECTIONPRES.

ABUND.

Hole
FOSSILCHARACTERFOSSIL

ZONE

AGE

Site 189

SILT RICH CLAYSTONE
olive gray to olive black (5Y 4/1 - 2/1)

LITHOLOGIC DESCRIPTION

VOID

0.5-

1

2

1 1 1 1 1 11 11 1 1 11 1

SILT RICH CLAYSTONE
olive gray to dark greenish gray(5Y 3/2 - 5GY 4/1)

Explanatory notes in Chapter 1

366Core Catcher:D- -1 1 1 1 1
1 1 1 1 1
1 1 1 1 1

Core
Catcherbedding inclined 30°
burrows

N- R- S- PF BF FSITE 189
WET-BULK DENSITY, gm/cc
SECTION

CM

I T

ro

Grain
Density-a2 o

POROSITY,*
100
0

T

l

l

|

J3§>

M
0-1

1-

-25

2-

-50

3-

-75

5-

-100

6-

7-

-125

9-1

150 I

189-17-1 189-17-2 189-18-1 189-18-2

367

SITE 189
Core 19-

CUTTINGSII
1 1 I I II i i i i i i i i i i i i i i i i i
1 1 1 1 1 1 1 1 I I 1 I I I I I l ! l l l 1 ! l I
1 1 1 1 1 1 1 1 II 1 1 1 II 1 II 1 II 1 1 I I
I l l l l l I l l l l l Illll!i!i!i!i!i!i!i!i

1

Core 20

CLAY RICH LIMESTONE (10-15% clay)
Basic lithology
SILT RICH CLAYSTONE
olive gray (5Y 3/2)
average composition 85% clay, 15% silt

•47
bedding inclined 30-40°
128devitrified VITRIC ASH, 70% glass, 25% feldspar, 5% opaque,chlorite, etc.

Cored Interval:865-871

METERSSECTIONPRES.

ABUND.

Hole
FOSSILCHARACTERFOSSIL

ZONE

AGE

Core
Catcher90

LITHOLOGY

LITHO.SAMPLE

CSI

1 1 1 1 1 1 1 1 1 1 1 1

1.0-

Site 189

LITHOLOGIC DESCRIPTION

VOID

0.5-

0
N
R
S

LITHO.SAMPLE |LITHOLOGY

DEFORMATION |Cored Interval: 847-856

METERSPRES.

ABUND.

FOSSILZONE

AGE

FOSSILCHARACTER

DEFORMATION |HoleSECTION

Site 189

LITHOLOGIC DESCRIPTION

VOID
0.5—

1

CSI

•
• • • lN
RS

• • • • l

D

•-

PF
BF

Core
Catcher

Explanatory notes in Chapter 1

368

1 I 1 1 1 I I l I 1 I 1 1I

1.0-

100
SILT RICH CLAYSTONE
olive gray - olive black (5Y 4/1 - 2/1)
burrows, bedding inclined 30°:

130

XR 2-70
52% amorph.
35% quartz
8% plag.
4% mica
2% chlor.

SITE 189
WET-BULK DENSITY, gm/cc
1

2

POROSITY,*
100
0

SECTION
CM

3

ro

Grain
Density
-32 o
M
ù-i

H

-

h-100

hl25

9-1

-i5o ml
189-19-1 189-19-2 189-20-1 189-20-2

369