12. SITE 54
Shipboard Scientific Party1

SITE DATA

Occupied: July 17-19, 1969.
Position: Sediment apron west of Iwo Jima Ridge:
Latitude: 15° 36.6'N.
Longitude: 140° 18.10'E.
Water Depth: 4990 meters.
Cores: Nine cores.
Total Depth: 294 meters in pre-Middle Miocene basalt.
MAIN RESULTS

Site 54 confirms the history recorded at Site 53: anepisode of basaltic flows—of Paleogene or earliest Miocene age—was succeeded by an episode of explosive
vulcanism and ash deposits in Miocene time. The regional scale of the basalt flows suggests that the underlying crust may be of Tertiary age, though we cannot
exclude the possibility that the basalts form only ablanket over older basement.
The Miocene ash falls were concentrated on the western
flank of the Iwo Jima Ridge, suggesting that this ridge
was the source.
BACKGROUND

additional supply of beacons, on July 19. The ship
steamed somewhat west of south from Site 53, searching for a prospective drill site in the more westerlyparts of the sediment apron flanking the Iwo Jima
Ridge. Further west lay rough basement topography
with little sediment; to the east lay, presumably, thickand coarser volcanoclastics. The seismic profile continued to show fairly flat, well-defined sediments lappingout against basement highs. On approaching the 15th
parallel a site was chosen on the flank of a high (Figure
1, also see Chapter 11, Figure 1), a short section which
could be drilled quickly, if necessary—leaving enoughtime to meet the Ran Annim closer to Saipan if thisship should be unable to meet Glomar Challenger so
far out to sea.
The geologic setting appeared rather similar to that at
Site 53; the profiler showed sediments overlapping onto
the flanks of basement highs. But some of the individual
basins showed very flat tops, and a strikingly levelstratification, with more distinct wedging-out of units
on the gentle flanks; a suggestion that turbidity current
sedimentation may have played a larger role here.
Bottom soundings in the area of Site 54 are given as
Figure 2.
OPERATIONS

The general background for drilling in the Philippine
Sea has been dealt with in connection with Site 53.
The discovery there of Miocene tuff and ash on a complex of basaltic flows and pyroclastics with interbedded
limestone, of Oligocene or early Miocene age, resembling the section on Guam, suggested that this sequence
might be regional rather than local; more drilling seemed
essential to substantiate or reject this interpretation.

The beacon was dropped at 1200 hours July 17, andthe hole spudded at 2000 hours. A tungsten carbide
bit cut the volcanic ash section somewhat more rapidly
than the light diamond bit used at Site 53. Nine cores
were cut, the upper seven in ash, the lower two inbasalt.

At the same time, the authors' plans were restricted (1)by the limited distribution of a sufficient sediment
cover for spudding in, and (2) by the need to meet the
M.V. Ran Annim, coming out of Saipan with an

An attempt was made to log this hole, but the logging
tools met an obstruction 55 meters above the bit. The
center bit was similarly stopped. The hole, therefore,
had to be abandoned, and on bringing out the drill
string the obstruction turned out to be a piece of basalt
which had dropped out of the core barrel and lodged
in the pipe.

B. C. Heezen, Lamont-Doherty Geological Observatory; A. G.
Fischer, Princeton University; R. E. Boyce, Scripps Institutionof Oceanography; D. Bukry, U.S.G.S. La Jolla; R. G. Douglas,
Case Western Reserve University; R. E. Garrison, Universityof California, Santa Cruz; S. A. Kling, Cities Service Oil Company; V. Krasheninnikov, Academy of Sciences of the U.S.S.R.;
P. Lisitzin, Academy of Sciences of the U.S.S.R.; A. C. Pimm,
Scripps Institution of Oceanography.

M.V. Ran Annim from Saipan met the Glomar Challenger at this site. It brought a supply of new beacons,and W. Allinder, to replace Dan R. Bullard, as operations
manager.
The site was abandoned at 2200 hours, July 19.
349

TAU
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19 JULY 1969

36700

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HOURS

Figure 1. Challenger bathymetric and magnetic profile at Site 54.
NATURE OF THE SEDIMENTS

Nine cores taken from one hole at this site provide
spot samples of the interval between 83 and 294 meters
below mudline. Two lithologic units were encountered:(1) Gray volcanic ash, comparable in age and lithology to Unit C at Site 53. This unit is over 187
meters thick at Site 54 (the top and bottom contacts
were not cored), compared to the approximately 153
meters present at Site 53. At Site 54 this unit is present
in Cores 1 through 7.
(2) Volcanic rocks, comparable in lithology to
Unit E at Site 53; sampled by Cores 8 and 9.
Units A, B, and D of Site 53 were not encountered at
Site 54, probably because the appropriate intervals
were not cored.
The volcanic ash at this site very closely resembles Unit
C of Site 53. The major difference, aside from increased
thickness, is that at Site 54 the volcanic ash is calcareous wherever sampled, whereas only the top part is calcareous at Site 53.
350

The ash is generally poorly sorted and contains, in addition to the dominant volcanic glass, common toabundant clay minerals. The glass is predominantly
colorless and unaltered, and is commonly in the formof elongate shards with tubular vesicles, as at Site 53.
Also present are small amounts of light brown glass(Chapter 38) and weakly birefringent, altered glass. Calcareous nannofossils, most notably large discoasters, arean abundant constituent in all ash samples examined(Chapter 38). Throughout the ash there are also substantial amounts (5 to 10 per cent) of very fine-grained,anhedral calcite particles that are mostly less than 5
microns across; although this material may represent
altered or disaggregated nannofossils, it is tentatively
considered of non-skeletal, possibly diagenetic origin.
Minor constituents of the ash include tests of planktonic foraminifera and Radiolaria, sponge spicules, andangular grains of Plagioclase, quartz, amphibole, pyroxene, mica and opaque minerals. X-ray studies by Rex
suggest in addition the presence of considerable amountsof cristobalite which, however, was not identified visually in the smear slides.
Predominant grain sizes in the ash are in the silt to sandrange, but there are a few dominantly clayey andFigure 2. Bottom soundings in area of Site 54.
pebbly layers. There are also a few obviously graded
beds in which the grain size decreases upward from abasal portion composed of coarse pumice pebbles. In
consistency, the ash varies from water-rich, incoherent
layers (usually the coarse sandy ash layers) to firm andcoherent beds (typically the finer-grained layers); someof the latter appear moderately cemented. The color
is dominantly gray to dark gray-brown although Core
5 recovered pebble size clasts of gray, black, white,green and red pumice and lithified tuff.
Cores 8 and 9 recovered about 160 centimeters of volcanic rock capped by a breccia (Plate 1). The breccia(Plate 1A, Figure 1), 15 to 20 centimeters of which wasrecovered, consists of angular clasts of vitreous black

volcanic glass and dark gray, aphanitic volcanic rock cemented in a fine-grained, white to pink tuffaceous matrix containing clay minerals, fine-grained Plagioclase,
zeolites (?) and iron oxides, and sand-size grains of volcanic glass. The matrix is cut by thin, randomly oriented
calcite veins. Most of the clasts are elongate, with theirlong dimensions oriented at high angles to the core margins. Most of the clasts of glass have outer rims, 2 to 3
millimeters thick, of yellow-brown palagonite. Refractive index measurements of the black unaltered glass given = 1.585, indicating a basaltic composition (48 to 50
per cent silicon dioxide, d = 2.80).
The top of the underlying volcanic rock is marked bya thin (5 to 10 millimeters), discontinuous rim of351

changes or the relative amounts of volcanic glass andclay present in these ash beds.

TABLE 1
Summary of Coring at Site 54

Interval Cored(below mudline)

Porosity, Wet-Bulk Density and Water Content

RecoveryCore No.

(ft)

(m)

(ft)

(m)

54.0-1

273-30383.2-92.4

16

4.8

54.0-254.0-354.0-454.0-5452-482

127.8-146.9

6.4

639-669

194.8-203.9
203.9-213.1

21
6
6
4

54.0-654.0-7669-699699-729729-759857-887

213.1-222.2
222.2-231.3
261.2-270.4

54.0-854.0-9958-961961-963292.0.292.9
292.9.293.5

21
13
3
2

1.8
1.8
1.2
6.4
3.9
0.9
0.6

Water depth: 4990.2 meters (16,372 feet)banded, black vitrous glass which resembles the rim ofa pillow lava (Plate 1, Figure 2). This contact is very irregular and locally appears to have been offset along
small faults. Erosion along the contact has removed theglass rim in places, and this probably supplied clasts foroverlying breccia.
Most of the volcanic rock is dark gray-brown, hydrothermally altered olivine basalt with variolitic texture
and is described by Melson elsewhere in this report. The
basalt is laced by a network of veins and pockets ofsecondary calcite (see Chapter 38), and Plate 1, Figure
3, fine-grained tuffaceous material, and clear euhedralzeolite crystals (probably harmotome). Some of the
thicker veins are composite, having sparry calcite along
one or more margins and white tuffaceous material in
the middle; others change along the length of the vein
from calcite-filled to zeolite-filled. Although no interlayered limestone beds were encountered, as at Site 53,
a small light brown limestone clast is enclosed in basalt
at about 15 centimeters above the base of Core 8.
PHYSICAL PROPERTIESCoring disturbance prevented these physical properties
from accurately representing in situ conditions.
Natural Gamma Radiation

Natural gamma radiation emitted from Miocene calcareous volcanic ash, recovered from 83 meters to 266
meters below mudline in Hole 54.0, averaged 550
counts/7.6-cm core segment/1.25 minutes. Radiation
limits were 200 to 900 counts, which is small. There isno consistent variation with depth. What small variations occur between cores are probably due to porosity
352

Porosities and wet-bulk densities of Miocene calcareous
volcanic ash (83 to 266 meters) averaged about 62 percent and 1.54 g/cc at Hole 54.0, with a minimum porosity of 43 per cent and a maximum density of 1.75 g/cc.
Water content ranged from 38 to 54 per cent, typically
being 42 per cent. Porosities and water contents did
not appear to decrease with depth. Some porosity variations were probably related to grain size variations.
Sediment Sound Velocity
Sound velocities through the Miocene calcareous volcanic ash, at Hole 54.0 (83 to 266 meters), ranged from1.59 to 1.89 km/sec, averaged 1.72 km/sec, and varied
irregularly with increasing depth. Between 82 and 270
meters below the mudline, the sediment is compact
gray volcanic ash with average core sound velocities
ranging from 1.64 to 1.83 km/sec. The volcanic glasscontent of this ash varies from 55 to 70 per cent. Thereis a close correlation between sediment compactness
and sound velocity. The lowest sound velocities were1.64 km/sec (averaged over the interval of 83 to 90
meters) and here the penetrometer values averaged 38
X I0"1 millimeters. The highest sound velocities were1.77 to 1.88 km/sec through sediments recovered between 223 and 231 meters, which were associated witha low average penetrometer measurement of only 0.4
X I0"1 millimeters.
At a depth of 292 meters below mudline, hard volcanic
rock was encountered by the drill. The uppermost 15
centimeters of this rock comprised black vitreous volcanic glass fragments in a matrix of fine-grained volcanic
glass. Two sound velocity measurements of 3.68 and3.74 km/sec were obtained. Below the glassy breccia
was an altered basaltic rock with sediment sound velocities ranging from 5.16 to 5.74 km/sec. The average offive measurements was 5.44 km/sec.
Penetrometer

Average penetrometer values for each core recovered inHole 54.0 ranged from 4 to 38 X I0"1 millimeters in this
Miocene volcanic ash (83 to 270 meters), the complete
range being from zero to complete penetration. The
penetrometer completely penetrated the coarse soft
watery ash in the top 50 centimeters of Core 1 (82.2
meters below mudline). The penetrometer values have a
direct variation with the sediment sound velocity values.
Thermal Conductivity

Two thermal conductivity measurements were made in
volcanic ash from Hole 54.0. Core 1 (depth of 86
meters below mudline) had a thermal conductivity of
2.13 X I0"3 c a l ^ C W 1 sec"1, and Core 3 (depth of 195
meters to 204 meters) 2.04 X lO^cal^C^cm^sec* 1 .

CONCLUSIONSAs at Site 53, the sediments consist mainly of Miocene
volcanic ash. They include some beds of pumice tuff,
somewhat coarser than those seen at Site 53. The composition of the glass, as determined by refractive indices,
ranges from andesitic to basaltic. The occurrence ofsome graded beds supports the view that some of theseash beds may have been resedimented by turbidity currents.
The bulk of the section penetrated is of Middle Miocene age.
Although the water depth is similar to that at Site 53,
and the sediments are of the same general character,
Site 54 shows a much better preservation of calcareous

fossils. Foraminifera are common, as are heterococcoliths, whereas at Site 53, the biota was largely reduced
to the most solution-resistant discoasters.
The sediments are underlain by a basaltic lava flow,
with a mantle of basaltic glass breccia.
The general history at Site 54 seems to correspondclosely to that at Site 53, and at Guam. The eastern
Philippine Sea appears to have as geophysical basementa basaltic (on Guam, andesitic also) lava complex withinterbedded sediments of Eocene-Oligocene and possibly early Miocene age; and, this is succeeded by mixed
andesitic-basaltic pumice tuffs and ashes, erupted fromthe ridges in Miocene time. Site 54 has made no directcontribution to the age of the basal flow sequence,other than that it is pre-Middle Miocene.

353

PLATE 1
Volcanic rock recovered from acoustic basement at Site 54 in
the Philippine Sea.

354

Figure 1

Breccia comprising angular clasts ofblack glass and dark gray aphanitic rockin a fine-grained white to pink tuffaceous
matrix. Most of the clasts have outer rimsof yellow-brown palagonite.

Figure 2

Contact between breccia above andvolcanic rock. Note very irregular anddiscontinuous rim of black glass along
contact. Veins of calcite and whitetuffaceous material cut volcanic rock.

Figure 3

Hydrothermally altered olivine basalt
cut by veins similar to those describedin Figure 2.

/****%,'•

Plate 1.

355

HOLE 54.0

AGE

LITHOLOGIC DESCRIPTIONSER1ES-SUBSERIES

ASH, dark gray, s i l t size with very thin black ash beds showing
graded bedding; top part of core is dark grayish brown, watery,coarse grained ash

MIDDLE MIOCENECALCAREOUS ASH and CLAY, gray, dark gray

EARLY MIDDLEMIOCENE

CALCAREOUS ASH, dark gray; some coarse sand size grains of pumice
and glass
CALCAREOUS ASH, gray

EARLY MIDDLEMIOCENEEARLY MIDDLEMIOCENEEARLY MIDDLEMIOCENEEARLY MIDDLEMIOCENE

120

160

200

Coarse sand and pebbles of l i t h i f i e d TUFF, PUMICE, and CALCAREOUS
ASH
240

ASH, gray - light gray, calcareous in lower part, few pebbles of
PUMICE also occur

CALCAREOUS ASH, dark gray brown, gray brown
FLOW BRECCIA of black glass fragments 1n white matrix overlyinghydrothermal ly altered OLIVINE BASALT flow rock
OLIVINE BASALT, dark gray brown, altered, contains numerous veinsof white tuffaceous? material and sparry calcite

Figure 3. Summary oflithology in Hole 54.0.

356

EARLY MIDDLEMIOCENE

HOLE: 54.0
DEPTH
IN
HOLE

NATURAL GAMMA
RADIATION

WET-BULKDENSITY

WATER CONTENTANDPOROSITY

COUNTS/7.6cm/1.25min

M

, wt
5000

1.4

1.8

2.2

20

40

SOUND
VELOCITY

THERMALPENETROMETERCONDUCTIVITY

% vol
60

80

100

0 •

1.6

1.8

2.0

2.2

X10" J
cal/(°C cm sec)

XI<>•• mm

2.0

100

ao

4.0 0

200

300

i i i i r

20-

40.

60-

80-

100-

120-

140-

160-

180-

200-

220-

~r
240-

260-

280-

300-

3.68 to 5.74 kii/sec

320-

340-

360-

380-

400-

420-

440-

460-

480-

i

i i

i

i i

i i i

i

i

i

i i

•O = LABORATORY- ATMOSPHERIC BACKGROUND COUNT.

Figure 4. Summary of physical properties in Hole 54.0.

357

er
m

a.

LU
H-

-I

03

03

LITHOLO
*t

*
•''•*

-2

1

ö.

1 _ -3

1

5," * »

0-

1
-4

0

ft ^ "

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*

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=
-^ ^ ^f/

Q

SE

SMEARJ

Q LU
Q <_>PALEO 1

s
o

LU LU

s

2-

7
•

1

p
0

LU

z

σ>

1I0C

LU

* »%***»**'.»"»* *"* *"2 ?**•**'**' • |p * (

-II

Q

03

-12

cm

a

4 : -13O ö
03 Q) α0 a Q

03O<~-* 1O

£ O ^
O K ö

*

*

3

LITHOLOGIC DESCRIPTION M

This section has numerous t h i n(1-50 mm) black ASH beds showing
graded bedding dark gray (10YR 4/1)*

* ***« " * **4

0 . 20j 21
22
23* j a* ^ * *

5

24

- 25
8: 26
- 27
- 28
- 29

6

cc

*
*

Dark gray ash

Figure 5. Summary oflithology in Hole 54.0 Core 1.
358

σ

0
CSI

CO

,0
0"-

S
3

54 33 13
ASH
Dark grayish brown (10YR 4/2)
watery, coarse-grained, mainlycomprising glass, pumice, andpalagonite with some quartz,
opaques, pyroxene, hematite,
mica, rads, s p c l , foram, nanno,
and clay minerals
ASH
Dark gray (10YR 4/1), firmer,
si I t - s i zed
Glass (andesitic) A
Clay R
Quartz R
Foram R
Rads and Spcl R
Nanno R
FeldsparOpaques
Total CMica
Pyroxene (mono)

*

-I0

- -18
- 19

D E P T H 83.2-92.4m

3 95

2 54

4

7 80 13 42

6

i 88 11 40

3

*
*

-14

-17

54.0

,1 *

** " \-"«"»: -16« V 03**V' >" «»'*

3: inIU

LU
—I
Q

*

*

-6

f

HOLE

<

>-

SECTION

ZONE

AGE

LU
<j>
(r>
t—

LEG
CORE

LU

LJLJ

CORE: 54.0-1
DEPTH
NATURAL GAMMA
IN
RADIATION
CORE

WET-BULKDENSITY

COUNTS/7.6cm/1,25min

M

$ *0

WATER CONTENTANDPOROSITY
%wt

g/cc
5000

1.4

1.8

2.2

20

40

%vol
60

80

100

1.6

VELOCITYCONDUCTIVITY

km/secX10' 3cal/(°C cm seel

1.8

2.0

2.2

2.0

3.0

4.0

0

100

200

300

o
o

5-

•O = LABORATORY-ATMOSPHERIC BACKGROUND COUNT.

Figure 6. Summary of physical properties in Hole 54.0 Core 1.

359

LEG
CORE

HOLE

54.0

DEPTH

FORAMINIFER A

292,1mNANNOPLANKTON

RADIOLARIA

Very scarce and small

Assemblages of the lower

Radiolaria are common (notOrbulina universa, Candorbu-

middle Miocene Sphenolithus

abundant) in the top of thelina universa^ Globigerina

heteromorphus Zone arecore and rare in the middle

bulloides, G. oonoinna, G.

present throughout the core.

and bottom parts.

parabulloides, G. quinqueloba,Species present include

Sectionone contains species probably

G. falaonensis determine the

Cycloaoaoolithina leptoporus> of the middle Miocene

age of sediments only as theC. neogarmation, Disooaster Cannartus pettevssoni Zone.

Middle Miocene (perhaps theaulákos, D. brouweri 8.1.3

upper part of the Globorota-

D. deflandrei, D. exil•is, D. sent the next lower zone,

lia fohsi Zone, lower Middlevca>iábilis, Heliaopontos~

Doroadospyris alata, also

Miocene).

phaera kamptneri, andmiddle Miocene.

Spehnolithus heteromovphus.

section 2 radio!arians are

Retiaulofenestra pséudoum-

too rare to indicate abilioa is present only at

definite zone.

the top of the core.

TOP:

Species in section 2 repre-

Below

Cannartus latioonus,

Stichoaorys deVmontense,
Cyrtooapsella cornuta,
Lithopera neoter a, L. baoaa,
L. fhornburgi, andCyrtoaapsella tetrapera.
SECTION 2: Stiβhoaorys
delmontense3 Calcoσyoletta
oostata, Cyrtooapsellacornuta.

Figure 7. Summary of biostratigraphy in Hole 54.0 Core 1.

360

SECTION1— 0 cm— 150

Plate 2. Photographs of Hole 54.0 Core 1.
361

en
LU

LU

UJ
_l

o_
<

UJ
_J
<

LEG
CORE

HOLE

54.0

DEPTH

137.8-146.9 m

COi I <| LITHOLOGY DESCRIPTION

CO

co

-1
-2
-3
-4

5
-6

-8
•9

5--io
-12

5

4-

Q
Q

ASH
Dark gray (2.5Y 4/0)
Glass D
Plag and Hornbl A
Foram RCALCAREOUS CLAY with ASH
Gray (2.5Y 6/0)
Clay A
Plag and Opaques C
Non-skeletal Calcite A
Rad C
Glass A
Nanno RCALCAREOUS ASH
Dark gray (10YR 4/1)
Glass A Clay R
Nanno A Plag and Opaques A
Rad and Spcl R
CALCAREOUS ASH and CLAY
Gray (5Y 5/1)

-14

CALCAREOUS ASH
Gray (5Y 5/1)
Glass A
Nanno C-A

-15

Non-skeletal Calcite C
Light gray (2.5Y 7/0)

-13

CALCAREOUS ASH with CLAY
Gray (2.5Y 6/0)
with rare mottles l i g h t gray andblack (45-50 cm)

QI

20

••22

24

8:

cc
Figure 8. Summary oflithology in Hole 54.0 Core 2.

362

69 26

47

78 22

70 30 46 12

89 10
79 19 38

78 21 40

CORE: 54.0-2
DEPTH
NATURAL GAMMA
IN
RADIATION
CORE
µ
M

<β

WET-BULKDENSITY

COUNTS/7.6cm/1.25min
0

WATER CONTENTANDPOROSITY

g/cc
5000

1.4

1.8

% wt
2.2

20

40

THERMAL PENETROMETERCONDUCTIVITYSOUND
VELOCITY

km/sec
€0

100

1.6

i I I i i

1.8

2.0

cal/(°C cm sec)
2.2

2.0

3.0

4.0

0

100

200

CP
300

r

o
o

2—

5—

*O = LABORATORY-ATMOSPHERIC BACKGROUND COUNT.

Figure 9. Summary of physical properties in Hole 54.0 Core 2.

363

LEG
CORE

HOLE

«°

DEPTH

137.8-146.9 m

FORAMINIFERANANNOPLANKTON

RADIOLARIA

Some samples of this core

Assemblages of the lower

Radiolaria are common at thecontain rare and small

middle Miocene Sphenolithus

top of this core, rare toward

planktonic Foraminifera ofheteromorphus Zone are

the bottom.

the Globovotalia fohsi Zone,

present throughout the core.

assemblages are of the lower

lower Middle Miocene.

Species present include

middle Miocene Doroadospyris

Assemblages include

CyatoaoaoolT thina neogamma- alata Zone.

Candorbülina universa,tior y Disooaster bvouweriTOP:

Globorotália praemenardii,

s.I.j D. ohallengeri, D.

Cannartus laticonus,

G. óbesa, G. saituladeflccndr>eiy D. exi•tisy D.Cyrtooapsella covnuta,

pvaescitula, G. mohleri,vaviabilis3 Disaolithina sp. Lithopera neotera, Dor>oados-

Well preserved

Stichocor>ys sp.t

Globiger>inoides ivr>egularis, [large], Helioopontosphaera pyris alata, Lithopera
G. trilobus, Globigerina

kamptneri, and Sphenolithus

venzae, and L. bauevi.

parabulloides, G. juvenilis

hetevomovphus.

BOTTOM:and single specimens of
Or>bulina univer>sa, Globigerinoides bisphaerioa,
Globoquadrina dehiscens,
Sphaevoidinellopsis grimsdalei.

Figure 10. Summary of biostratigraphy in Hole 54.0 Core 2.

364

Stiohoaorys wovffii.

CORE
SECTION

1

— Ocm

EMPTY

EMPTY

EMPTY

Plate 3. Photographs of Hole 54.0 Cores 2 and 4.
365

CC
LU
QG

u

O

GO

O
N

LU
CO

δ

<

o

o g
Lu

PAL
SM

üJ

0_

LIT

Lu
_l
<

UJ

LEG
CORE 3HOLE
DEPTH

LITHOLOGIC DESCRIPTION

54.0
194.8-203.9 m

σ
CO

ASH

Dark gray (10YR 4/1)
calcareous, some coarse sand size
grains of pumice and glass

-2
-3
-4

»*
II

»

-5
-6

2:. 7
-8
-9

y•\o
-12

OC

4:•i3

-14

DD

CO <» <3

— 15
ö eg

EAR1

a•wS

•i-i ^ co

" O ^
O S ö

:•i6

o-: - i 7
:•i8

19
20
:-2l

: -22
rJ

-23

oo

1 l•l

24

CC
Figure 11. Summary oflithology in Hole 54.0 Core 3.

366

67 31

12

CORE: 54.0-3
DEPTH
NATURAL GAMMA
IN
RADIATION
CORE

WET-BULKDENSITY

COUNTS/7.6cm/1.25min
M

<Λ

*o

WATER CONTENTANDPOROSITY

g/cc
5000

1.4

1.8

%wt
2.2

20

40

SOUND
VELOCITY

THERMAL PENETROMETERCONDUCTIVITY

cal/(oC cm see)

%vol
60

80

100

i i i i i

1.6

1.8

2.0

2.2

2.0

10

4.0 0

100

200

300

r

1—

4-

*O = LABORATORY-ATMOSPHERIC BACKGROUND COUNT

Figure 12. Summary of physical properties in Hole 54.0 Core 3.

367

LEG βCORE 3

HOLE 54.0
DEPTH 1948•2O39

FORAMINIFERANANNOPLANKTON

RADIOLARIAThis core can be attributed

Assemblages of the lower

Radiolaria are abundant at

to the Globorotalia fohsi

middle Miocene Sphenolithus

the top of the core, rare at

Zone of lower Middle Miocene.

heteromovphus Zone are

the bottom. The assemblages

Poor assemblages of plank-present throughout the core.

present probably represent

tonic Foraminifera consist ofSpecies present include

the lower middle Miocene

rare Candorbulina univevsa,

Cyolocoaootithina neogarma-

Dovoadospyris alata Zone.

Glóbigevinoides tvilobus, G.

tion} Disaσaster bvouwer>i,

TOP: Stiohooorys delmon-

irvegulavis, Globigevinas.l.3 D. ohallengevi, D.

tense, Cannartus latioonus3

foliata, Sphaeroidinellopsis

deflandrei, D. exilis, D.

Cyrtooapsella covnuta, andgrimsdalei.

variábilis, Disoolithina sp.

Dovoadospyvis sp.

[1arge], Helieopontosphaera

BOTTOM: Stichoaorys delmon-

hamptneviy and Sphenolithus

tense, S. wolffii (?), andheteromorphus.

Cannartus latiaonus.

Figure 13. Summary of biostratigraphy in Hole 54.0 Core 3.

368

LEG
CORE

to

er

LU-

LU
CD

<

<t

INI t

o

o

i—

M-

DEPTH

54.0
2

.9-213.1 m

<Λ
i

—ir-

co

o

LLJ

er
<
SME

c
(n

LU

Q

PALI

LU

HOLE

LITHOLOGIC DESCRIPTION

•σ

c
σ
CO

> • .

CO
,o

o

zc.

q

44

8

CM

-1

1

-2
1 -3

1

*

*

-4
*

-5
•6

2:

7

" (
. O

0

• *•*';'"**«

2

-9

*

*
m

\ 1 * *t*

CALCAREOUS ASH
Gray (5Y 6 / 1 , 2.5Y 5/0)
Glass A
Nanno C
Non-skeletal C a l c i t e C
Foram R
Rad and Spcl R
P l a g i o c l a s e , opaques R
Section 2 sediment i s very f i r m andcoherent

3: -I0
-i i

11

OCENE

-12

i—a

LU
O
Q

4: -13

|

EARI

i

-14

5J•§

•lb

05

j ^
>-

--16

" r * CO

ii
0) O

3

-17

--18

4

-19
c~

I i i

0 . 20-21
22

7 : 23524cx>

1 I.I 1

25
26

; 27
- 28
- 29

6

cc

*
*

Figure 14. Summary oflithology in Hole 54.0 Core 4.

370

2 78 20 43 11

CORE: 54.0-4
DEPTH
IN
CORE

NATURAL GAMMA
RADIATION

WET-BULKDENSITYK

COUNTS/7.6cm/1.25min

g/cc

WATER CONTENTANDPOROSITYSOUND
VELOCITY

THERMALPENETROMETERCONDUCTIVITY
× 1 0 -3

M

<Λ

0

5000

1.4

1.8

% wt
2.2

20

40

% vol
60

80

km/sec
100

1.6

1.8

2.0

x10-1 m mcal/(°C cm sec)
2.2

2.0

3.0

4.0 0

100

200

300

2-

5-

*O = LABORATORY-ATMOSPHERICBACKGROUND COUNT.

Figure 15. Summary of physical properties in Hole 54.0 Core 4.

371

LEG
CORE

HOLE • «DEPTH

FORAMINIFERA

203-9-213.1 m

Very poor assemblages of theAssemblages of the lower

Radiolaria are abundant in

Globorotalia fohsi Zone,

middle Miocene Sphenolithus

the top of the core and rare

lower Middle Miocene, were

heteromorphus Zone areat the bottom.

traced throughout the core.

present throughout the core.

blage represents the lower

Planktonic Foraminifera are

Species present include

middle Miocene Doroadospyris

presented but rare

Cyaloaoaoolithina neoganvna-

alata Zone.

Candorbulina waiversa,

tion3 Disooaster brouweriTOP:

Globorotalia obesa, G.

s.l.3 D. ohallengeri, D.

tense> Calocyclas eostatat

may evi, Globigerina foliata, deflandrei, D. exilis, D.

Cytoaapsella cornuta, C.

G. conoinna, Globigerinoid.esvariàbilis, Disaolithina sp.

tetrapera, and Doroadospyris[large], Helicopontosphaera

alata.

sis grimsdalei.

kamptneri, and Sphenolithus

BOTTOM:

Figure 16. Summary of biostratigraphy in Hole 54.0 Core 4.

The assem-

Stiohooorys delmon-

trilobus, Sphaeroidinellop-

heteromorphus.

372

RADIOLARIANANNOPLANKTON

Stiohooorys wolffii.

UJ

LU
CD

UJ

o

LJ
_l
<
CO

<

o
LU
CO

N

3

LEG
CORE

HOLE 54.0
DEPTH 213.1-222.2 m

CO

o
2 c

LITHOLOGIC DESCRIPTION

-1

-2
-3
-4
-5
-6

2;. 7
-8
-9

y •io

-I2

B•

4J -I3•I4•i5

Core liner collapsed - sedimentstored in plastic boxes.
Recovered sediment of two types:
1. Rounded coarse sand to pebble
size clasts of multicolored(gray, black, white, green,red) lithified TUFF and PUMICE.
Material is well sorted, but thismay be a drilling phenomenon.
Many elongate pumice slivers
with pipe-like vesicles.
2. Soft, gray, calcareous ASH
components of sand size:
Glass A
Nanno A
Non-skeletal Calcite C
Feldspar and Hematite C
Clay R

: i6
»V

o

17

os «

i8
:•i9

20

;•22

24

8:

cc
Figure 17. Summary oflithology in Hole 54.0 Core 5.
374

LEG βCORE

HOLE

FORAMINIFERA
None.

213.1-222.2 m

RADIOLARIANANNOPLANKTON
Assemblages of the lower

This core contains common

middle Miocene Sphenolithus

representatives of the lower

heteromorphus Zone are

middle Miocene Dovoadospyris

present throughout the corealata Zone.

Species present include

TOP:

Cyoloaoaaolithina neogamma-

BOTTOM:tion, Discoaster> br>owoevi

tense, S. wolffii, Doroado-

s.l.y D. ohallengeri3 D.

spyris alata, and Cyvtooap-

deflandvei, D. exilis, Dsella japonioa.

not examined.
Stichooor>ys delmon-

vaviabilisy Discolithina sp,[large], Helicopontosphaera
kamptneri> and Sphenolithus
he teromor>phus.

Figure 18. Summary of biostratigraphy in Hole 54.0 Core 5.
375

I

I

^

S

δ

S5

<

Z

Q

^^―,

QJ

UJ z

LEG β
CORE βHOLE *•»DEPTH
M I •i•>•S 2 d g 5,

% 8 ë p g 5 it

M-|d°|á1

LITHOLOGIC DESCRIPTION g g g f g-ISection not opened as sediment very
wateryiI:• -4''»»»ii

i

VΛVV

ASH

46 45

—-5

[;&;•'

Gray (5Y 5/1)

36 56 8

' 6.

\\V"****

Glass

0

•'

er

•

*

*

?;,":.%%*„

-j

0

9

3

D A

"

Feldspar, Opaques C» VΛ'*,*

Nan no R• J v .V*

Non-skeletal Calcite R/»;vv; ** Pebbles of red, brown and gray pumice

ΔΔ

^

I

'

3 i-to— ?#$:>:,V»;:';>:•-n:*v,-';• *:>%*- -12 -3 -<VΛ Λ§Λ ;V V-'.:. * *

UJ

f,

5
o

S 4 : -13
Iβ
•

2

fc•

•*

UJ

05Ö

§

ts

£

' -14

:

IE

<
m

:•i6

^

:* i

J^

&§ "

W

•%';••>)•*"/.**.*
I**i»W**:

Nanno R-Cd» foram, spcl R*: :V/; * "V-f V.v: » ,V»*.:[&>< >. | 8 " . V HΛ;*.v '. V '' *i\\K

-21

:-25~
--26

27

u 73 13 43 11:

ASH Calcareous, Sections 4 and 5

Gray (5Y 6/1)

G^SS
A
cla
C A

y ~

Nanno

c

Non-skeletal Calcite C
Feldspar and opaques R
Rad> SPC1 R

0 76 24 44 7

*YA'λ

•22 C ; vVv
I
0 .V .*".V
7--23
| w:
•
»•*!*,'
8

^ A

Ra

'-19
'**;!*"** *J":*-:*
6" yQ — * : ;'• %-•"*"—:

Cla

Λ,*'\";^ § J - ._
17 Λ

_]

0 74 26 44 14
ASH
G^y (SY 5/1), light gray (5Y 7/1)
Glass A*

Gray (2.5Y 6/1)

6

"•28
--29

I

I LO h>>>vj * I

Figure 19. Summary oflithology in Hole 54.0 Core 6.
376| | I | I

CORE: 54.0-6
DEPTH
NATURAL GAMMA
IN
RADIATION
CORE

WET-BULKDENSITY

COUNTS/7.6cm/1.25mir

WATER CONTENTANDPOROSITY

g/cc
5000

i

1.4

i

i

i wt

1.8

I

i

2.2

i

i

20

i

i

40

i

SOUND
VELOCITY

THERMAL PENETROMETERCONDUCTIVITY
XIO• 5cal/(°C cm sec)

% vol
60

80

100

1.6

1.8

2.0

2.2

2.0

3.0

4.0

X10"'

0

100

200

300

r

>

4-

7-

r

*O = LABORATORY-ATMOSPHERIC BACKGROUND COUNT.

Figure 20. Summary of physical properties in Hole 54.0 Core 6.

377

LEG
CORE

HOLE
DEPTH

FORAMINIFERA
None.

NANNOPLANKTON

RADIOLARIA

Assemblages of the lower

The top part of this core

middle Miocene Sphenolithus

contains no Radio!aria, butheter>omorphus Zone arethey are abundant in thepresent throughout the core,

middle part and somewhat lessSpecies present include

abundant at the bottom,

Cyclooocoolithina neogamma-

Species of the lower middle

tion, Disooastev brouweri

Miocene Dorcadospyris alatas.l.j D. challevgeri, D.

Zone are present.

deflandvei, D. exilis, D.

MIDDLE: Stichoaor>ys delmon-

var>iabilisj Bisβotithina sp. tense3 T>ovoadospyvis alatas[large], Helioopontosphaeva

Cannavtus laticonus,

kamptneri, and Sphenolithus

Cyr>tocapselZa japonica^ andhetevomovphus.

Calocycletta costata.
BOTTOM: Stiahoaorys delmontense3 S. wolffii3 Cyrtoaapsella Qaponica, Cannavtus
laticonuSj and Caloayaletta
costata.

Figure 21. Summary

378

of biostratigraphy in Hole 54.0 Core 6.

SECTION— Ocm

2

Plate 4. Photographs of Hole 54.0 Core 6.
379

Lu

LU

LU
_J
<
U
if)

<

3

^

O

O

o

CD

LEG
CORE

HOLE 54.0
DEPTH

LITHOLOGIC DESCRIPTION

LJU

CO

o
CO

CM

-I
-2

•4

35 55 10 40

5ASH calcareous
Dark gray brown (2.5Y 4/2), graybrown (2.5Y 5/2), dark gray (2.5Y 3/0
Glass A
Nanno C-A

-6

-8

Non-skeletal Calcite R
Clay R-C-9

Plag and Hematite R-C
Rad and spcl R

J--I0

o
o

:
4
I,

85 14 41

Yellow brown (10YR 5/6)
Light brown gray (2.5Y 6/2)
Light gray (2.5Y 7/2)
84 16

-14

DC
*„*»»»•**

20

r8:

cc
Figure 22. Summary oflithology in Hole 54.0 Core 7.

380

84 16 42

CORE: 54.0-7
DEPTH
NATURAL GAMMA
IN
RADIATION
CORE

WET-BULKDENSITY

WATER CONTENTANDPOROSITY

COUNTS/7.6cm/1.25min

wt
5000

1.4

1.8

2.2

20

SOUND
VELOCITY

km/sec

% vol

40

60

80

THERMAL PENETROMETERCONDUCTIVITY

100

1.6

i

1.8

cal/(°C cm sec)

2.0

2.2

2.0

3.0

4.0

0

100

200

300

i i i I i r

X
o

2-

o
o

o
o
4-

1

I

I

I

I

I

I

I

I

I

i

i

i

i

i

i

i

*O = LABORATORY-ATMOSPHERIC BACKGROUND COUNT.

Figure 23. Summary of physical properties in Hole 54.0 Core 7.

381

LEG
CORE

HOLE «-•
DEPTH

FORAMINIFERA
None.

261.2-270.4 m

RADIOLARIANANNOPLANKTON
Assemblages of the lower

Radiolaria are rare

middle Miocene Sphenolithus

throughout this core.

heteromorphus Zone are

Species present indicate apresent throughout the core.

middle Miocene age, probablySpecies present include

the Voroadospyris alata

Cyclocoocolith•ina neogamma- Zone.
tion, Disaoaster brouweriTOP:

8.1.j D. ahatlengeri, D.

BOTTOM:

deflandrei, D. exilis, D.

tense, Cyrtooapsellavariábilzs, Disaolithina sp.

japonioa.

[large], Helicopontosphaera
kamptner>i, and Sphenolithus
heteromorphus.

Figure 24. Summary of biostratigraphy in Hole 54.0 Core 7.

382

Stichooorys sp.
Stiohooorys delmon-

en

er

UJ

LU

LU
<t

LU
_J
<

<
to

o

or

CO

LU

O
N E

LU
CO

m
_l

C/)

LEG

β

CORE 8HOLE •"
DEPTH

292-292.9 m

LITHOLOGIC DESCRIPTION

+1
2
3
4
5
6

+7

f

1 w < "..

FLOW BRECCIA - angular pieces of
black glass, partly to completely
palagonitized, in matrix of w h i t i s h ,fine grain ?tuffaceous matrix
HYDROTHERMALLY ALTERED OLIVINEBASALT FLOW ROCK - dark gray brown,
amygdaloidal rock with f e l t e d massof reddish brown, prismatic
Plagioclase, sometimes in rosettes,
in a fine grain matrix. Veins ofwhite ?tuffaceous material andsparry calcite common

3+io
See section description
:•i3
14

i5
:•i6

+20
+21
74-23
•24

cc
Figure 25. Summary oflithology in Hole 54.0 Core 8.

383

|
LU

i

< z

g

^ g ^ y

LEG

6

HOLE

™

CORE
CORE

99

DEEPPTTHH 292.9.293.5m
292.9-293.5n,
D<^1^

1 11 UTHOLOGIC DESCRIPTION j | j } |

•- I

I;•4

v^/;v
^Λ/'/'1'C< l~\\a~"."^

HYDROTHERMALLY ALTERED OLIVINEBASALT - dark gray brown, altered,numerous veins of white tuffaceous
material and sparry calcite;•6..0 L.

See section description

3:-10—

Vl2

3

:•i3

J

4

;•I4

—-15
:-i6

5

:- 4
--18
--19
;-2l

7: -23

J

:•24

:-25
8

:-26

27

6

--28
_-29_

1 1 c c I i~l
Figure 26.

384

Summary of lithology in Hole 54.0 Core 9.

IMM

CORE
SECTION— 0 cm

1

CC

25

EMPTY
50

EMPTY

EMPTY
125

EMPTY

—150Plate 5. Photographs of Hole 54.0 Cores 7, 8 and 9.
385

HOLE 54.0
CORE 8SECTION 1

rr Ocm —

•J

--25

--50

--75

-1

-I

1

v

< .

FLOW BRECCIA: angular pieces of black glass inwhite to pinkish matrix. The glass fragments
tend to be elongate, are orientated at an angle
to long axis of core, and range in size from 1
to 30 mm. Most of glass has thin rims (2-3 mm
thick) of yellowish brown & red brown palagonite& some is completely connected to palagonite.
The matrix comprises very fine glass fragments,
clay minerals & zeolites(?), and small amountsof carbonate. Calcite-filled veins also present.

CONTACT: this is very irregular and is in places
marked by a thin rim (5-10 mm thick)of banded,
vitreous black glass. In other places the blackglass has a very irregular wispy appearance, orr U < \
4 -i
has been completely removed & contributed clasts
to the overlying breccia. The contact has been
offset along small fractures. The basal part of
the flow breccia along the contact contains someangular, very large (8 cm) pieces of the underlying volcanic rock.
OLIVINE BASALT: strongly hydrothermally alteredpillow lava. Rock contains felted mass ofreddish brown prismatic calcite, sometimes inrosettes, in a fine grained dark gray brown
matrix. Numerous veins of sparry calcite andwhite tuffaceous sediment; many of the latterveins have palagonitic walls in the country rock.
In places there are unfilled vugs in some ofthe veins.

--100

--I25

*—>- 150
Figure 28. Summary oflithology in Hole 54.0 Core 8 Section 1.

386

HOLE 54.0
CORE 9SECTION 1

0cm —
U -J

7

r > v

--25
f -i <•> r--50

OLIVINE BASALT: Dark gray brown hydrothermallyaltered flow rock - same as 54.0-8-1. Thin
section shows subophitic texture with irregularly
shaped patches of altered groundmass, scatteredolivine granules, rare areas composed mainly ofolivine and Plagioclase with but minor pyroxene.
Plagioclase laths reach 1 mm in length, but are
mainly smaller. Microphenocrysts of Plagioclase& olivine up to 1.5 mm across. Olivine andgroundmass extensively altered. Numerous veinsof 2 types:
1. thin (1-3 mm) veins entirely to partiallyfilled with sparry calcite
2. thicker (up to 10 mm) veins containing
white to yellow white tuffaceous material,
slightly calcareous; material in veins is a
mixture of sand-size glass fragments, lightcolored tuff, fine frain glass, clay
minerals, & calcite. Many of these veinshave a thin sparry calcite margin.

--75

100

--I25

-M50
Figure 29. Summary oflithology in Hole 54.0 Core 9 Section 1.

387