6. SITE 89 - Deep Sea Drilling Project Reports and … further detail on the Sigsbee Abys-sal Plain, see the "Background and Objectives" sections in chapters 3, 4, 5, 7, and 8. The

6. SITE 89

The Shipboard Scientific Party1

SITE DATAOccupied: March 5-7, 1970.

Position: 20°53.41'N;95°06.73'W.

Water Depth: 3067 meters.

Total Depth: 440 meters.

Holes Drilled: One.

Cores Taken: Six.

BACKGROUND AND OBJECTIVES

The Bay of Campeche is bounded on the north by theSigsbee Abyssal Plain. This abyssal plain has been formedby abyssal sediments liberally supplemented by turbidites.A large fraction of the turbidites comes from the north andeast, while there is a modest contribution apparently fromthe south and west. For further detail on the Sigsbee Abys-sal Plain, see the "Background and Objectives" sections inchapters 3, 4, 5, 7, and 8.

The Bay of Campeche is bounded on the south by thecontinental slope and shelf, and the Isthmian embayment,which is described in detail by Murray. (1961). The Isth-mian embayment is, in turn, bounded on the east by theYucatan platform, on the south and southwest by theSierra Chiapas and on the west by the Sierra Madre Orien-tal. The embayment is made up of two basins. The VeraCruz Basin to the west, is separated by the Tuxtla upliftfrom the Tabasco-Campeche Basin to the east. DuringJurassic times, evaporites were deposited in many parts ofthe Tabasco-Campeche Basin.

On the east, the Bay of Campeche is bounded by theCampeche Scarp and the Campeche Bank. The bank ismade up of Cretaceous and Tertiary calcareous sedimentslaid down in essentially horizontal sheets. The bank andscarp are discussed more fully under the "Backgroundand Objectives" section of Chapters 2 and 3 and in the"Discussion and Interpretation" section of Chapter 3.

In the Bay of Campeche, just west of the CampecheScarp, lies the north and slightly westward trending Cam-peche Canyon, apparently an avenue allowing detrital car-bonates to be deposited within the predominantly clasticprovince of the Sigsbee Abyssal Plain. To the west of theCampeche Canyon lies the uplifted area of knolls (Worzel,

J. Lamar Worzel, Marine Biomedical Institute, University ofTexas, Galveston; William Bryant, Texas A&M University (co-chiefscientists); Arthur O. Beall, Jr., Continental Oil Company (leadsedimentologist); Kendell Dickinson, United States Geological Sur-vey; Robert Laury, Southern Methodist University; Lee AndersonSmith, ESSO Production Research (lead paleontologist); BlakeMcNeely, Shell Oil Company; Helen P. Foreman, Oberlin College;Roy Capo, Lamont-Doherty Geological Observatory.

et al., 1968; Ballard and Feden, 1970), which is about 60miles wide and might well be called the "Campeche-Sigs-bee Salt Dome Province." West of this province is a nar-row zone about 20 miles wide with a northward dippingcontinental rise, which is named the Vera Cruz gap. Justwest of this zone lies the eastward dipping continental riseof the eastern coast of Mexico. In this zone lies the foldedareas which may be related to salt tectonics as describedby Bryant et al., 1968. There is a narrow shelf along theeastern coast of Mexico on the western side of the Bay ofCampeche. The north-south trending ridges act as barriersagainst the movement of sediment westward into the ba-sin. Thus, it is suggested that the Site 89 area receives verylittle sediment contribution from the west.

Hole 89 was drilled near Site 8 on the lower part of theeastern Mexico continental rise almost where it joins theVera Cruz gap, approximately midway between the twozones in which salt tectonics is believed to be active. Thepurpose was to ascertain the sedimentary regime withinthis zone of the Bay of Campeche, where salt tectonicsapparently were not active, so that it could be comparedto the sedimentary regime of Hole 88.

The Glomar Challenger cored at Site 89 on March 5and 6. Six cores were recovered from the interval betweenthe sea floor and 440 meters. Coring results are given in thecore inventory (Table 1).

NATURE OF THE SEDIMENTS

General Description

Site 89, situated on the Gulf of Campeche continentalrise, represents an opportunity to compare rise sedimenttypes with a somewhat more isolated bathymetric highsuch as at Site 88, located on the crest of a salt diapir. AtSite 89, the sequence penetrated consists largely ofpelagic carbonate oozes down to approximately 350 me-ters, whereupon a Late Miocene quartzose and volcano-genie hemilaminite-dominated interval was penetrated.These latter sediments represent a change in depositionalsetting, in that pelagic processes of sedimentation wereequalled by low energy turbidity current deposition. Inview of the position of Site 89 on the continental rise, itis suggested that the Miocene hemilaminite facies repre-sents a peripheral deposit to the main axis of depositionof northern abyssal plain and southern continental risesedimentation.

Cores 1 through 5 generally can be described as green-ish gray (5G6/1 to 7/1), moderately to strongly burrowed,clayey, ashy, foraminiferal, nannofossil ooze with variableamounts of volcanic ash occuring as laminae or in burrow-mixed ash-rich zones. As an exception there is an upper-most thin interval of tan (10YR5/4) foraminiferal ooze,

71

SITE 89

TABLE 1Core Inventory - Site 89

Core

1

2

3

4

5

6

Total

% Cored

% Recovered

No.Sections

3

1

4

6

1

5

20

Date

3/5

3/5

3/6

3/6

3/6

3/6

Time

2130

0000

0230

0600

0930

1930

Coreda

Interval(m)

3067-3070.5

3117-3126

3186-3195

3287-3291

3366-3372

3443.3447

Cored(m)

3.5

9.0

9.0

4.0

6.0

4.0

35.5

8.0%

Recovered(m)

3.5

0.5

6.0

9.0

0.5

6.5

26.0

73.2%

SubbottomPenetration

(m)

Top

0

50.0

119.0

220.0

299.0

376.0

Bottom

3.5

59.0

128.0

224.0

305.0

380.0

440.0

Lithology

Foram nannoooze

Foram nannoooze

Foram nannoooze

Foram nannoooze

Nanno ooze

Nanno ooze

Age

LatePleistocene

MiddlePleistocene

EarlyPleistocene

EarlyPliocene

LateMiocene

LateMiocene

Drill pipe measurement from derrick floor.

and a slightly thicker interval of yellow brown (10YR6/4),vaguely laminated, slightly to moderately burrowed,clayey, foraminiferal nannofossil ooze. Minor fecal/FeSstains occur throughout the cores.

Volcanic ash is considerably more abundant at Site 89than at Site 88. Glass occurs not only as burrow fill butalso in quantities sufficient to produce bands. Shards arepoorly sorted, very angular, and generally have a mediandiameter in the fine sand size. Clear, brown, vesicular(pumice), striated, and exceedingly iron-rich varieties ofglass were observed. Accompanying the glass are equallypoorly sorted but smaller quantities of apparently vol-canogenic components such as sanidine, zoned plagio-clase, hornblende, and biotite.

Core 6 consists of green olive gray (5GY5/1-5G6/1),well laminated, sparse to moderately burrowed, nannofos-sil-rich clay and clayey nannofossil ooze, with occasionalthin laminae of quartzose and ashy silt and/or very finesand (texturally graded with sharp base). Larger burrowsare often filled with terrigenous silt. Detrital carbonatemakes up a small percentage of clasts in the silts. Miocenesediments at Site 89 differ appreciably from Miocenesediments of Sites 3 and 87, in that the former are lesscarbonaceous and finer grained. In view of the limitedsample available, however, this comparison must be tenta-tive.

Sedimentological Interpretation

Sedimentation on the continental rise in the vicinity ofSite 89 has been dominated by pelagic processes since atleast late Late Miocene time. The abundance of volcanicash debris suggests proximity to a source which is quitedifferent from the situation at Site 88 (intermediate) andSites 2 (Leg 1) and 86 (far). It is also interesting to note

that the Plio-Pleistocene section at Site 89 is somewhatthicker than the stratigraphic equivalent at Site 88,suggesting closer proximity to a source of terrigeneous claydebris.

A change in sediment type, as typified by Core 6, sug-gests that during middle Late Miocene (and older) sedi-mentation, the continental rise at this locale wasdominated by low energy turbidity currents (see Beall andFischer, 1969). These sediments, described as laminitesand hemilaminites/hemipelagites, represent a period ofincreased sediment influx into the basin as well as into thislocale. The turbidite-dominated Miocene sections at Sites3, 87, 90 and 91 reflect a contemporaneous high rate ofsedimentation on the abyssal plain to the north of Site 89.

The portion of the continental slope and rise referredto as the Veracruz Gap in this report is here consideredas a probable primary axis of sediment transport duringat least Miocene time. Site 89, somewhat peripheral to theGap and on the easterly dipping segment of the continen-tal rise, would thus occupy a rather peripheral positionwith respect to the introduction of turbidites into the abys-sal plain. Within this context, the laminite facies describedat the base of Site 89 would either reflect deposition ofdiffuse low energy turbidites in a setting removed from themain axis of sediment introduction and deposition, ormight possibly reflect a more local introduction of fineelastics from the nearby, easterly dipping continentalslope. The presence of the ridge/swale topography in thislatter area, if present during Miocene time, would seem aless favorable path of sediment introduction via turbiditycurrents. In either case, Miocene sediments present atSite 89 appear to represent a generally southeasternsource of elastics. The abundance of volcanic debristhroughout the sequence is also strongly in favor of prox-imity to a volcanogenic source terrain, e.g., mainlandMexico.

72

SITE 89

Physical Measurements

Penetrometer, GRAPE, and natural gamma measure-ments were determined on at least portions of all cores. Asat Site 88, only a few sonic velocity measurements weremade, primarily due to the presence of trace amounts ofnatural gas in the intermediate cores.

Natural gamma measurements range around 3,000counts, very similar to Site 88. Some of the ash-rich zoneshave counts in excess of 3,500. Core 6 has a somewhathigher average count, suggesting that the more abundantterrigenous clay, as well as a lower carbonate content, isresponsible. Sediment at this level is somewhat more con-solidated, which should also be reflected in the naturalgamma count, composition being held constant.

Bulk density determinations show an increase withdepth, suggesting normal consolidation. As at earlier sites,the bulk density values appear low by at least a factor ofabout 0.2 g/cc. Penetrometer readings also reflect consoli-dation with depth, showing a more or less steady increaseto a value of approximately 10 in Core 6 (which marks thearbitrary semiconsolidated to consolidated stone bound-ary). Refer to Beall and Fischer (1969), for further discus-sion on a proposed scale of consolidation usingpenetrometer data.

The presence of methane at this site suggests that themechanism of natural gas generation proposed for Site 88is plausible. The hypothesis that most of the methane isbiogenic and generated at intermediate depths appears tobe valid.

BIOSTRATIGRAPHY

The biostratigraphy of Site 89 (adjacent to Site 8) issummarized in Figure 1. The interpretation is based onexamination of the foraminifers and calcareous nannofos-sils. The samples also were examined for radiolarians, butno significant occurrences were noted.

Sample 1 (10-89-1, CC):Globorotalia truncatulinoides, G. flexuosa, G. menardii,Globigerina inflata, Globigerinoides ruber (pink), Spha-eroidinella dehiscens (rare), Nonion pompilioides, Ge-phyrocapsa oceanica, Reticulofenestra sp., Scapholithusfossilis, Cyclococcolithus leptoporus leptoporus, Coccoli-thus sp. cf. C. pataecus, Cyclococcolithus annulus, andDiscosphaera tubifer.

Age: Late Pleistocene (Wisconsinan)Globorotalia truncatulinoides Zone; Pulleniatina finalisSubzone.Environment: Bathyal.Remarks: Glass shards (volcanic) were noted in the finefraction of the washed residue.

Sample 2 (10-89-2, CC):Globorotalia truncatulinoides, G. scitula, Globigerinainflata, G. eggeri, Globigerinoides ruber (rare), Spha-eroidinella dehiscens (abundant), Helicopontosphaerasellii, Cyclococcolithus leptoporus leptoporus, C. an-nulus, Coccolithus pataecus, Scyphosphaera pulcher-rima, Pseudoemiliania lacunosa, Gephyrocapsaoceanica (rare), and G. sp. cf. G. caribbeanica.

Age: Middle Pleistocene (Yarmouthian) Globorotalia trun-catulinoides Zone; Globoquadrina dutertrei Subzone.Environment: Bathyal.Remarks: Glass shards (volcanic) and rare reworkedCretaceous, Paleocene, and Mio-Pliocene calcareous nan-nofossils were noted.

Sample 3 (10-89-3, CC):Globorotalia truncatulinoides (rare), G. miocenica(abundant), G. pertenuis, G. crassaformis (rare), Globig-erinoides obliqua, Globigerina inflata, Discoasterbrouweri, D. pentaradiatus, Pseudoemiliania lacunosa,Coccolithus pataecus, Cyclococcolithus leptoporus mac-intyrei, Discolithina millipuncta, and Scyphosphaerapulcherrima.

Age: Early Pleistocene, probable late Nebraskan: Globoro-talia truncatulinoides Zone, Globorotalia tosaensis Sub-zone.Environment: Bathyal.

Sample 4 (10-89-4, CC):Globigerina nepenthes, Globoquadrina altispira,Globorotalia acostaensis, Globigerinoides obliqua extre-mus, Discoaster brouweri, D. pentaradiatus, D. surculus,D. asymmetricus, Sphenolithus abies, Ceratolithus tri-cornulatus, Reticulofenestra pseudoumbilica, andPseudoemiliania lacunosa.

Age: Early Pliocene: Globorotalia margaritae Zone.Environment: Bathyal.Remarks: A marked increase in benthonic foraminiferswas noted.

Sample 5 (10-89-5, CC)Globorotalia sp. afF. G. mayeri, G. miocenica, Globo-quadrina altispira, G. venezuelana, Globigerina nepen-thes, Globigerinoides obliqua extremus, Discoaster bollii,D. exilis, D. hamatus, D. quinqueramus, D. brouweri,Reticulofenestra pseudoumbilica, Sphenolithus abies,Helicopontosphaera sellii, Scyphosphaera pulcherrima,and Craspedolithus nitescens.

Age: Late Miocene: Globorotalia acostaensis Zone.Environment: Bathyal.Remarks: Reworked foraminifers noted include Globoro-talia fohsi fohsi (Middle Miocene) and Globorotalia spinu-loinflata (Middle Eocene). Among the calcareousnannofossils, a reworked Eocene assemblage was noted,including Chiasmolithus grandis, Coccolithus eopelagicus,Discoaster barbadiensis, and Marthasterites tribrachiatus.

Sample 6 (10-89-6, CC):Globorotalia mayeri, C. sp. cf. G. acostaensis,Globigerina nepenthes, Globoquadrina triloba, Orbulinauniversa, O. suturalis, O. bilobata, Discoaster brouweri,D. bollii, D. quinqueramus, D. exilis, Sphenolithusabies, Reticulofenestra pseudoumbilica, Cyclococcoli-thus leptoporus macintyrei, C. sp. cf. neogammation,and Craspedolithus nitescens.

Age: Late Miocene: Globorotalia acostaensis Zone.Environment: Bathyal.Remarks: Common reworked Cretaceous and a few re-worked Paleocene calcareous nannofossils were noted.

73

SITE 89

SITE 89 WATER DEPTH 3067 METERS

RELATIVEAGE

APPROXIMATEYEARS

(MILLIONS)

ZONESAND

SUBZONES

SUBSURFACEDEPTH

(METERS)

COREAND

INTERVAL

HOLOCENE

LATE

1.0

? MIDDLE

EARLY

? LATE

? MIDDLE

EARLY

2.1

LATE

G. tumida1

Pulleniatinafinalis

Globoquadrinadutertrei

50

100

Globorotaliatosaensis

Pulleniatinaobliquiloculata

Globorotaliamargaritae

119

ihlff.

150

200

220-

250

300299

Globorataliaacostaensis

350

376-

400

440?

Figure 1. Biostratigraphic summary of Site 89.

74

SITE 89

Sample 7 (10-89-from water ports on drill bit, 440 meters)Discoaster brouweri, D. quinqueramus, D. exilis, D. sp.cf. D. hamatus, Cyclococcolithus neogammation, C. lep-toporus macintyrei, Reticulofenestra pseudoumbilica,Sphenolithus abies, Helicopontosphaera kamptneri, H.sellii, Coccolithus pelagicus, s.l., C. minutulus, C. pata-ecus, and Craspedolithus nitescens.

Age: No older than Late Miocene; probable Globorotaliaacostaensis Zone.All material examined was from bit and drill collarsbrought up from 440 meters below the sea floor. It is notknown that any of the material was from the very bottomof the hole. Material scraped from outside the drill collarwas definitely Pleistocene and no material was recoveredfrom the center bit.Remarks: Cretaceous and Eocene reworked calcareousnannofossils were identified from the assemblage.

DISCUSSION AND INTERPRETATION

Site 89 was drilled on the outermost part of the east-erly dipping continental rise off the eastern coast of Mex-ico, near its junction with the Vera Cruz Gap (the20-mile-wide northerly dipping continental shelf and risewhich falls between the easterly dipping continental slopeand rise off the eastern Mexican coast, and the westerlydipping margin "Campeche-Sigsbee Salt Dome Prov-ince"). The on-station profile record is shown in Figure 2.Six cores were taken, over a depth range of 380 meters,consisting of pelagic carbonate organogenic oozes withintermixed volcanics for the Pliocene and Pleistocene sec-tion, changing to a quartzose, volcanic-rich, terrigenousclay turbidite section, intermixed with calcareous pelagicoozes in the Late Miocene. The uppermost section isslightly to moderately burrowed, with occasional volcanicash layers. The volcanic ash here is more abundant thanat Site 88, suggesting that this site is closer to the sourcearea of the volcanic ash.

The thin turbidite layers intermixed with the pelagicsedimentation in the Miocene suggest that this site waslargely protected from sedimentation from the west by thefolded zone of the Mexican continental slope. It receivedsmall turbidite contributions as peripheral deposits fromturbidites which may have flowed through the Vera CruzGap. After the Miocene, turbidite deposition largelyceased and pelagic sedimentation ensued, suggesting thateither the turbidite flows were more modest or ceasedaltogether.

Thus, this area appears to have been in a bathyal envi-ronment, receiving dominantly calcareous sediments withcontributions of terrigenous clays and sands from thesouth during Miocene times. Volcanic contributions,probably from the west, were more common in Miocenetimes than later.

Average sedimentary rates were 2.8 cm/103y in the LateMiocene, 3.7 cm/103y for the Pliocene, and 6.8 cm/103yfor the Pleistocene with an average rate of 3.8 cm/103yfrom the Late Miocene to the present. The rather lowPleistocene rates of deposition are the result of theprotected setting of Site 89. The average rate is about halfthe rate of deposition at Sites 3 and 88, which is reasonable

- 0080

CO

.-: α>

:'•'B

0060;

000L8 S/D

LO

I

l&.jpifeA!-;.-.-., -

|

002 L

68

•/« ,̂

•fi•

!

0 0

CD CO eo ^

75

SITE 89

in view of these latter receiving additional sediments,probably from the north and east.

Core 4, at 220 meters, outgassed moderately. The gaswas predominantly methane. For values of methanepresent, see the "Discussion and Interpretation" section ofChapter 5. Little or no gas was evident in the deeper cores,so it seems evident the gas is of biogenic origin.

It was decided not to continue the hole when the centerbit became stuck at a depth of 440 meters.

REFERENCES

Ballard, J.A. and Feden, R.H., 1970. Diapiric structures on theCampeche Shelf and Slope, Western Gulf of Mexico. Bull.Geol. Soc. Am. 81 , 505.

Beall, A.O. and Fischer, A.G., 1969. Sedimentology. In Ewing,W.M., Worzel, J.L. et al., 1969. The Initial Reports of theDeep Sea Drilling Project, Volume I. Washington (U.S. Gov-ernment Printing Office). 521.

Bryant, W.R., Antoine, J., Ewing, M., and Jones, B., 1968.Structure of Mexican Continental Shelf and Slope, Gulf ofMexico. Bull. Am. Assoc. Petrol. Geologists. 52, 1204.

Murray, G.E., 1961. Geology of the Atlantic and Gulf CoastalProvince of North America. New York (Harper and Bros.).692.

Worzel, J.L., Ley den, R. and Ewing, M., 1968. Newly Discov-ered Diapirs in Gulf of Mexico. Bull. Am. Assoc. Petrol.Geologists. 52, 1194.

76

SITE 89

SITE 89

AGE DEPTH(m)

LITHOLOGY

— 100

— 200

1 3

— 300

-400

LITHOLOGIC DESCRIPTION

1 : O l i v e brown CLAYEY ASHYFORAM NANNO OOZE w i t h vo l -canic ash-rich laminae/bands.

2: Greenish-gray CLAYEY FORAMNANNO OOZE.

3 and 4: As above but somewhatashy with volcanic ashlaminae/beds.

5: Greenish-gray, s l i gh t l yforamini feral CLAYEY ASHYNANNO OOZE with a few ashlaminae/bands.

6: Green-gray laminated NANNO-RICH CLAY and CLAYEY NANNOOOZE with occasionallaminae/bands of te×tura l lygraded s i l t or very f inesand.

POROSITY

4.0

DENSITYg/cc

2.0I

13.0

100I

2 NATURAL GAMMA10 counts/75 sec

25.0 37.0

PENETROMETER

cm

2 . 0

49.0

78

Site 89 Hole Core 1 Cored Interval: 0-3.5 m Site! Hole Core 3 Cored Interval: 119-128 m

Site!

LITHOLOGIC DESCRIPTION

CLAYEY FORAM NANNO OOZEYellow-brown (10YR6/4), vaguely laminated(wi th 10YR4/2); s l i g h t l y to moderatelyburrowed.

CLAYEY ASHY FORAM NANNO OOZEOlive-brown (5YR6/1 with mottles of 5GY6/1(ash) ) ; moderately burrowed wi th subsidiarylaminae/bands and burrow-f i l l /burrow-mixedvolcanic ash-r ich zones.

- V O I D

GRAIN SIZEWEIGHT %

3.2

2.2

14.482.4

10.5 87.3

Hole Core 2 Cored Interval : 50-59 m

AGE

|MIDDLE

PLEISTOCENE

(Yarmouth)

ZONE

m ~<ù^ o

1 -2

1}

SECT

ION

1

METE

RS

0.5-

1.0—

I

CoreCatcher

LITHOLOGY

VOID

=̂+̂ = ^

DEFO

RMAT

ION

LITH

O. S

AMPL

E

-

LITHOLOGIC DESCRIPTION

CLAYEY FORAM NANNO OOZEGreenish-gray (5G6/1 with subsidiary 5GY6/1,minor 5B5/1, and N3); moderately burrowed;minor FeS/fecal (N3) stain throughout.

GRAIN SIZEWEIGHT %

SAND

6.4

SILT

15.4

CLAY

78.2

0.5-

CoreCatcher

LITHOLOGY

- -fir

LITHOLOGIC DESCRIPTION

Expanded slightly by gas drive? Odorless.

-VOID

FORAM NANNO OOZEGreenish-gray (5G6/1, mottled with 5B5/1 and5GY6/1); moderate to strongly clayey; some-what ashy with laminae to beds of volcanicash and zones o f burrow-mixed ash and ooze.Sparse N3 fecal s t a i n . Most burrows f i l l e dwith volcanic ash.

GRAIN SIZEWEIGHT %

3.9

3.2

2 1 . 0 7 7 . 5

18.3

28.467.7

78.5

H

00

o Site 89 Hole Core 4 Cored Interval: 220-224 m

0.5-

CoreCatcher

LITHOLOGY

VOID

VOID

VOID

i -

Expanded by gas dr ive - odor less.

-VOID

-VOID

—VOID

CLAYEY FORAM NANNO OOZEGreenish-gray (5G7/1; subsid iary 5GY7/1,N3 and 5B6/1); somewhat ashy; s t rong lyburrowed. Minor fecal/FeS spot s ta i ns .

LITHOLOGIC DESCRIPTION

As above. Severely burrowed wi th a zone off a i n t , vague laminat ions (5G5/1) - Higherclay content?

— VOID

-VOID>VOID

Richer in ash as burrow-fill with onelamination very ash-rich.

/-VOIDAs above. Rare vague laminae.

As above. Severely burrowed with occasionalash-filled burrow. Rare vague laminae.

Increasing in ash content downwards. Noteash beds in lower part - partially alteredto brownish-gray clay.

GRAIN SIZEWEIGHT %

2.4

0.9

3.9

19.1 79.8

25.5

22.8 74.8

19.879.3

70.6

Site 89

AGE

| LATE MIOCENE

ZONE

Globorotalia aaostaensis

Hole

SECT

ION

1

METE

RS

0.5 —

1 . 0 -

-

CoreCatcher

Core 5

LITHOLOGY

VOID

g•JJ÷-AL•÷

VOID

DEFORMATION

Cored Interval: 299-305 m

LITHO. SAMPLE

-

LITHOLOGIC DESCRIPTION

CLAYEY ASHY NANNO OOZEGreenish-gray (5G6/1 with subsidiary 5G7/1,5G5/1); s l i g h t l y foramini fera l ; moderatelyburrowed; vaguely laminated with a few ashlaminae/bands. Bur row- f i l l also ash. MinorN3 s ta in .

GRAIN SIZEWEIGHT %

SAND

0.3

SILT

32.1

CLAY

67.6

Site 89 Hole Core 6 Cored Interval: 376-380 m

LITHOLOGY LITHOLOGIC DESCRIPTION

GRAIN SIZEWEIGHT %

0 . 5 - VOID

1.0-

UNOPENED

CoreCatcher

Sections 1-4 brecciated, severely disturbed.Sections 2 and 3 unopened. Similar to aboveand below.

(5GY5/1-5G5/1 with subsidiary 5G6/1 and N3);brecciated severely disturbed.

1.3 35.7 63.0

-VOID

-VOID

Laminated NANNO-RICH CLAY and CLAYEY NANNOOOZEGreen-olive gray ( intercalated 5GY5/1 and5G6/1); well laminated; sparsely to mod-erately burrowed with occasional th inlaminae/bands of quartzose (ashy) s i l t / V . F .sand, tex tu ra l l y graded with a sharp base.Larger burrows f i l l e d with s i l t .

*See Section Summary fo r more d e t a i l .

0.9 37.5 61.6

0 0

SITE 89

SITE 89 CORE 6 SECTION 5

O P

CO

LITHO DESCRIPTIONCOCO

VOID

- j

(.9,37.5,61.6; S i l ty clay)

VOID

Laminated NANNO RICH CLAY andCLAYEY NANNO OOZEGreen-olive gray ( intercalated5GY5/1 and 5G6/1); well laminated;sparsely to moderately burrowedwith occasional th in laminae/bandsof quartzose (ashy) s i l t / V . F . sand,tex tu ra l l y graded with a sharp baseLarger burrows f i l l e d with s i l t .

75

Intercalated5GY5/1 and 5G6/1

100-

125— - - _ " _ - _ -

5GY5/1 with N5 (sand); horizontal laminations below,cross-laminations above.

82

SITE 89

83

WET-BULK DENSITY, gm/cc

] 2 3I • ' • - M • H M • M | i u i | C M ^ ^ ^ ^

POROSITY,% G r a i n f° H I HO100 0 Density

I— I I 25 Btf

p- r X I 1 j H fi .«V J3Λ Λ I By JI' f I H HI 1

I r I !1

L. -100 I

•j -125

~ 9 H II 150 H B • K I WEmmd m mm

89-1-1 89-1-2 89-1-3

SITE 89

WET-BULK DENSITY, gm/cc

1 2 3

i i i i i ' ' ' • i

POROSITY,%100

P i r η

GrainDensity

- e M3 en Q _

CM

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Dl -

-25

2 -

-50

3 -

4—

-75

5 -

-100

7 -

-125

8 -

9- 1

•―150

89-2-1

84

WET-BULK DENSITY, gm/cc

GrainDensity

I 2 bhi M

0-η

1 -

2 -

3 -

5 -

6 -

7 -

8 -

9- 1

CM- 0

- 5 0

-75

- 1 0 0

-125

-150

SITE 89

89-3-1 89-3-2 89-3-3 89-3-4

85

SITE 89

WET-BULK DENSITY, gm/cc

1 2 3

89-4-1

86

WET-BULK DENSITY, gm/cc1 2 3

POROSITY,*100 0

GrainDensityI 2 ü

T π r ηM

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2 -

3 -

4 -

5 -

6 -

7 -

8 -

9- 1

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CM

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125

L-150

SITE 89

NO PHOTOGRAPH AVAILABLE

89-5

87

SITE 89

WET-BULK DENSITY, gm/cc

1 2 3

POROSITY,%

MO-i

CM

ro

3-4

k75

1-100

-125

9-J1—150

89-6-5