N PS ARCHIVE

1965
MONTEATH, G.

FNVIRONMENTAL ANALYSIS OF THE SEDIMENTS

"OF SOUTHERN MONTEREY BAY, CALIFORNIA

GORDON M. MONTEATH

MC :4IA

ENVIRONMENTAL ANALYSIS OF THE SEDIMENTS
OF SOUTHERN MONTEREY BAY, CALIFORNIA

by

Gordon M. Monteath, Jr.

Lieutenant, United States Navy

Submitted in partial fulfillment of
the requirements for the degree of

MASTER OF SCIENCE

United States Naval Postgraduate School
Monterey, California

19 6 5

-yarn-. , -, i-i-<i,tt-»lll

Library

U. S. Naval Postgraduate School

Monterey, California

ENVIRONMENTAL ANALYSIS OF THE SEDIMENTS
OF SOUTHERN MONTEREY BAY, CALIFORNIA
by
Gordon M. Monteath, Jr.

This work is accepted as fulfilling

the thesis requirements for the degree of

MASTER OF SCIENCE

from the

United States Naval Postgraduate School

ABSTRACT

Thirty-eight bottom sediment samples were collected in southern
Monterey Bay; these were analyzed for their textural and constituent
mineral compositions using coarse fraction analyses. Nine constituents
were recognized and their percentage concentrations in the various size
fractions of each sample were estimated.

Charts of the bay showing the sediment texture and the percentage
of each constituent in the sediments were prepared. The distribution of
the constituents and the relationship of each given constituent concen-
tration to the sediment texture and to the concentration of other con-
stituents were examined, and yielded the following results: the con-
stituent concentrations were found to lie in belts roughly paralleling
the shoreline. In general, terrigenous constituents (quartz, feldspar,
and mafics) occurred in highest concentrations along the coast in areas
of medium to fine sand, whereas pelagic constituents (foraminifera and
other organics) and authigenic minerals (glauconite and phosphorite)
were most highly concentrated in silts and clays occupying the outer
continental shelf. The area of authigenic mineral occurrence is con-
sidered to be essentially a non-depositional environment.

The factors controlling the marine depositional environment on the
shelf in southern Monterey Bay are the supply of sediments derived from
the Salinas River watershed and from shoreline erosion of the Monterey
Peninsula, the barrier to sediment influx from the north presented by
the Monterey Submarine Canyon, and the sheltering influence of the penin-
sula in creating a quiet area in the extreme southern end of the bay.

11

TABLE OF CONTENTS

Section Page

INTRODUCTION L

Background 1

Area description 1

Coastal physiography and geology 2

Constituent selection 8

PROCEDURE 10

Field sampling 10

Laboratory analysis 10

DATA ANALYSIS AND INTERPRETATION 15

Size distribution of sediments 15

Constituent analysis 15

Aggregates and Coprolites 17

Biotite 22

Foraminifera 26

Glauconite 31

Mafics 37

Phosphorite 44

Organic Debris 49

Quartz and Feldspar 54

Shell Fragments 57

SUMMARY AND CONCLUSIONS 61

Controlling factors 61

Distribution characteristics 61

ACKNOWLEDGEMENTS 63

BIBLIOGRAPHY 64

Appendix I Sources of Error in Estimation and Computation of

Constituent Concentrations 65

Appendix II Concentration of Constituents in the Sediment Samples 69

xxx

LIST OF ILLUSTRATIONS

Figure Page

1. Station Pattern 3

2. Submarine Geology 4

3. Coastal Geology 6

4. Sediment Distribution 16

5. Aggregates and Coprolites Distribution Chart 19

6. Aggregates and Coprolites Histogram 20

7. Photograph of Aggregates, Coprolites, and Biotite 21

8. Biotite Distribution Chart 24

9. Biotite Histogram 25

10. Foraminifera Distribution Chart 28

11. Foraminifera Histogram 29

12. Photograph of Foraminifera and Glauconite 30

13. Glauconite Distribution Chart 34

14. Glauconite Histogram 35

15. Glauconite to Biotite Ratio Distribution Chart 36

16. Mafics Distribution Chart 39

17. Mafics Histogram 40

18. Photograph of Mafics and Phosphorite 41

19. Mafics to Quartz-Feldspar Ratio Distribution Chart 42

20. Mafics-Biotite to Quartz-Feldspar Ratio Distribution Chart 43

21. Phosphorite Distribution Chart 46

22. Phosphorite to Organic Debris Ratio Distribution Chart 47

23. Phosphorite Histogram 48

24. Organic Debris Distribution Chart 51

iv

Figure Page

25. Organic Debris Histogram 52

26. Photograph of Organic Debris and Quartz-Feldspar 53

27. Quartz and Feldspar Distribution Chart 55

28. Quartz and Feldspar Histogram 56

29. Photograph of Shell Fragments 58

30. Shell Fragments Distribution Chart 59

31. Shell Fragments Histogram 60

LIST OF TABLES
Table Page

1. Example of Percentage Computations 13

VI

INTRODUCTION

Background

The purpose of this research was to investigate the depositional
environments of the bottom sediments on the continental shelf of south-
ern Monterey Bay, California. Too frequently in oceanographic and
marine geological literature, bottom sediments are described entirely
by their textural and mechanical properties. The environments of ma-
rine deposition cannot be characterized by size distributions alone,
because marine sediments are commonly made up of a variety of constitu-
ents, each having different physical, chemical, and mineralogical pro-
perties.

In this study 38 surface samples were collected; these were split
into coarse and fine fractions, and the coarse fractions were then ana-
lyzed for their constituent composition and their textural distribution.
Nine constituents were identified in the coarse fractions of the Mon-
terey Bay sediments, and a microscopic description, textural analysis,
and percentage estimation of each was made. Possible relationships
between the occurrence and amounts of each constituent were sought as
indicators of the depositional environments on the shelf. The methods
of coarse fraction microscopic analysis were first described by Shepard
and Moore (1954) and later summarized by Shepard (1963). Some modifica-
tions of these methods, which were made by the author in this study, are
described herein.

Area description

The area selected for study is located entirely on the continental
shelf in the southern half of Monterey Bay, California. It is bounded

on the north and west by the Monterey Submarine Canyon, on the south by
the rocky shoreline of the Monterey Peninsula, and on the east by a con-
tinuous sand beach backed by extensive sand dunes. The area, along with
the locations at which bottom samples were taken, is illustrated in Fig-
ure 1.

Sampling was restricted to depths of less than 75 fathoms for the
following reasons:

(1) The 75-fathom depth represents the approximate elevation of sea
level during the Wisconsin, or last glacial period, and most or all of
the area sampled has been transgressed by the ocean very recently.
Accordingly, ancient shorelines or relict sediments may be identified

on the basis of the sediment texture and composition and bottom topog-
raphy.

(2) Monterey Submarine Canyon, as delineated by the 100-fathora
curve in Figure 1, begins its descent on the seaward edge of the area
with a steep slope approximately at the 75-fathom line. The walls of
the canyon appear to be nearly devoid of sediment overburden, and repre-
sent the narrow continental slope plunging down to the abyssal environ-
ment of the deep sea floor. These environments have different character-
istics from the shallow water environments of the continental shelf.

The geology of the Monterey Submarine Canyon was the subject of a thor-
ough investigation by Martin (1963).

Coastal physiography and geology

The sediments of Monterey Bay were first described in detail by
Galliher (1932), and his interpretation of their textural distribution
is illustrated in Figure 2. Significant features of the distribution

STATION PATTERN

Figure 1

SUBMARINE GEOLOGY

'-S/ J

\l vl

1 ■" . ^

- J

v "" &

•

' \'X

1 '/J

^Jr

'C

rvV

»/ ls'/\

^i

k". 1 '-V-

1 '//J

Fine Sand
gGreen Silt &Clay
Coarse Sediments
Hrj Monterey Shale
E£j Sand Dunes

ES1C oarse & Medium Sand

■ — i —

V Fine Green-Gray Sand

Adapted from Gal liner, 1932

j.

Figure 2

are the gradation toward finer sediment sizes seaward from the coast,
the generally parallel transition from one size to another, the appear-
ance of "rock gravel" near the edge of the canyon, the extensive
granitic outcropping in the area west of Monterey Peninsula, and the
isolated patches of "rock and shell gravel."

Monterey Bay sediments were also studied by Galliher (1935) in con-
nection with the genesis of the mineral glauconite. The wide area of
green silt and clay on the central shelf is of special interest in this
regard and will be treated in the section concerning the glauconite
distribution within the region.

Phosphorite has been obtained from Monterey Bay and was discussed
by Emery and Dietz (1950). However, in the present study, the phos-
phorite content in most of the samples was found to be less than one
percent. The rarity of phosphorite is of particular interest and is
discussed in a later section.

Summarizing the marine geology studies accomplished by other inves-
tigators in the region, it is clear that Galliher 's work was, and re-
mains, a classic; however, more recent investigations have been few and
the area still lacks comprehensive coverage.

The coastal and land geology surrounding the area is illustrated in
Figure 3. The influence of this sediment source area on the environ-
ments within the bay is best illustrated by considering the mineral com-
position of the formations themselves. The Salinas River, which enters
the ocean near the northern end of the area, appears to be a main source
of the non-organic constituents of the sea floor sediments. The river,
which is intermittent and flows only during the rainy winter season,
varies widely in its discharge from year to year. It drains a large

COASTAL GEOLOGY

L EG E N D
l$ffil Sand Dunes

[-Recent

L | An

MM River Terrace Deposits —Pleistocene
Basalt —

Monterey Shale -

Salinas
River"

r-rr
\~t~n

Miocene

Ig^Marine Deposits (ss^congO-CretaQ

O

$£& Grani t ics — Mesozoic

Adapted from

State of Calif., Div of Mines

Santa Cruz Sheet, 1958

watershed in which shales, granitics, and metamorphic rocks outcrop.
Much of the coarser material introduced by the river was deposited in a
broad subdued delta adjacent to its mouth (Figure 1). Some of this ma-
terial supplied the adjacent beaches of the inner bay and some was prob-
ably transported down the canyon to the deep sea floor.

Several drainage areas in the extreme southern end of the bay,
including the El Estero drainage indicated in the figure, are very small
today and supply no sediments to the bay. They were active, however, in
supplying mainly marine shale erosion products to the sea floor when sea
level was lower than present, during late Wisconsin and post-Wisconsin
time.

The shoreline of the Monterey Peninsula itself is presently provid-
ing sediments to the bay. The mechanical action of waves, tides, and
currents in eroding the granitics of the protruding peninsula apparently
supplies a significant amount of quartz, feldspar, and hornblende to
the bottom complex.

It is probable that there are no significant sources of sediment
from areas to the north of the Monterey Submarine Canyon, since the can-
yon, which heads virtually at the shoreline at Moss Landing in the center
of the bay, serves as a barrier to sediment transport.

It is evident that the rate of supply of sediments to the southern
half of the bay has not been constant during Recent geological time.
The Salinas River, as well as the minor drainages in the southern end of
the bay, clearly supplied quantities of sediment during the time of
lowered Wisconsin sea level when the stream gradients were steeper and
the streams were incised in their channels. Wave erosion of the penin-
sula, on the other hand, has probably been more or less constant over

the same period; however, comparing the surface areas affected by this
process with the drainage area of the Salinas River, it is clear that
the contribution from the peninsula has been relatively minor compared
to that from stream drainage.

Constituent selection

Microscopic examination of the sediment samples revealed that they
are composed of at least nine distinctive constituents. These were thus
chosen to be studied with regard to their environmental significance in
the area. The constituents are:

(1) Aggregates and Coprolites — agglomerations of organic or mineral
matter cemented together by silt, clay, or organic secretion; fecal pel-
lets consisting of mineral grains are included.

(2) Biotite--a rock-forming mineral of the mica group.

(3) Foraminifera--planktonic and some benthonic tests of various
genera.

(4) Glauconite--a hydrous potassium iron silicate mineral of authi-
genic origin.

(5) Mafics--dark relatively heavy rock-forming minerals including
hornblende, tourmaline, epidote, and augite; this group excludes biotite.

(6) Phosphorite--a phosphorous mineral similar to apatite and be-
lieved to be precipitated authigenically.

(7) Organic Debris—plant fibers, wood fragments, sponge spicules,
diatoms, dinof lagellates, and other extraneous organic material.

(8) Quartz and Feldspar--the dominant rock-forming silicate miner-
als in this area.

(9) Shell Fragments --pieces of calcareous shells of pelecypods,

8

gastropods, other molluscs, etc., exclusive of foraminifera.

Quartz and feldspar, biotite, and the mafics are derived from the
adjacent coast, glauconite and phosphorite are formed in situ in the
ocean, shell fragments and foraminifera are formed organically and en-
tirely in the ocean, and aggregates -coprolites and organic debris are
derived both from land and marine environments.

PROCEDURE

Field sampling

Sampling was accomplished aboard the U. S. Naval Postgraduate
School's hydrographic research boat, a converted 63- foot Navy aviation
rescue craft. Core samples were taken using a Phleger corer which ob-
tained 1 1/2-inch diameter cores of various lengths depending upon the
size of the barrel chosen (one or two feet) and the hardness of the bot-
tom. A Dietz-La Fond clam shell snapper was also used, especially where
the presence of coarse sand or gravel bottom prevented penetration by
the corer. The sampling device used at each station is designated by
the letters C and G in the station nomenclature shown in Figure 1. A
valuable adjunct to the study would have been a box corer or a pipe
dredge, which might have supplied supplementary rock samples; however,
the research vessel was not equipped to handle equipment of this size.

The author recognizes the limitations imposed upon the results
through the use of these bottom samplers, primarily the problem of
achieving a sufficient density of stations to give a representative pic-
ture of the bottom sediment distribution. The textural and composi-
tional distributions of the sediments derived from this study revealed
generally well-defined patterns covering extensive parts of the area;
accordingly, the station density is considered adequate to reveal the
larger scale aspects of the distributions.

Laboratory analysis

Standard laboratory procedures were employed in carrying out the
coarse-fraction analysis of the samples. Shepard and Moore (1954) out-
lined the steps adequately; however, because of some minor variations

10

the steps are reiterated herein:

(1) Approximately five centimeters from the top of each core sample
or 50 grams from a grab sample was dried and weighed.

(2) Disaggregation was accomplished using a 0.01N solution of
sodium oxalate in which the sample was soaked for approximately ten min-
utes.

(3) The entire sample was washed through a 0.062 millimeter (250
mesh) standard Tyler sieve in order to separate the coarse fraction from
the fine. Both fractions were then dried and the fine fraction was
saved for possible future reference.

(4) A Tyler RoTap Sieve Shaker was used to sieve each coarse frac-
tion into standard Wentworth grade sizes.

(5) Each fraction was weighed, a cumulative frequency distribution
of the total sample was constructed, and the median grain size was deter-
mined.

Prior to submitting each size fraction of a sample to a microscopic
analysis, the fraction was split into four equal parts whenever the
fraction volume was sufficiently large. This was done so that an aver-
age of four visual constituent percentage estimates could be obtained,
rather than relying on a single judgment.

Utilizing the binocular microscope, each size fraction or part of
a fraction of each sample was examined and a visual estimate of the per-
centage of each of the nine constituents was made and recorded. Record-
ing of the percentages was accomplished by the use of a tape recorder
with a microphone conveniently secured near the base of the microscope.
This enabled the investigator to keep his eyes on the fraction while re-
cording successive percentage estimates. This was found to be quite

11

the steps are reiterated herein:

(1) Approximately five centimeters from the top of each core sample
or 50 grams from a grab sample was dried and weighed.

(2) Disaggregation was accomplished using a 0.01N solution of
sodium oxalate in which the sample was soaked for approximately ten min-
utes.

(3) The entire sample was washed through a 0.062 millimeter (250
mesh) standard Tyler sieve in order to separate the coarse fraction from
the fine. Both fractions were then dried and the fine fraction was
saved for possible future reference.

(4) A Tyler RoTap Sieve Shaker was used to sieve each coarse frac-
tion into standard Wentworth grade sizes.

(5) Each fraction was weighed, a cumulative frequency distribution
of the total sample was constructed, and the median grain size was deter-
mined.

Prior to submitting each size fraction of a sample to a microscopic
analysis, the fraction was split into four equal parts whenever the
fraction volume was sufficiently large. This was done so that an aver-
age of four visual constituent percentage estimates could be obtained,
rather than relying on a single judgment.

Utilizing the binocular microscope, each size fraction or part of
a fraction of each sample was examined and a visual estimate of the per-
centage of each of the nine constituents was made and recorded. Record-
ing of the percentages was accomplished by the use of a tape recorder
with a microphone conveniently secured near the base of the microscope.
This enabled the investigator to keep his eyes on the fraction while re-
cording successive percentage estimates. This was found to be quite

11

advantageous for maintaining "running" notes about various interesting
items and their relationships during perusal of the fractions.

The method used in calculating the percent of each constituent
within a sample, which varies slightly from that suggested by Shepard
(1963), was as follows: the percent of a constituent within a size frac-
tion was first estimated visually to at least the closest five percent;
this percentage was then multiplied by the weight of the fraction to
give the weight of the constituent within the fraction. These frac-
tional constituent weights were cumulated as a sum which represented the
total amount present within the coarse fraction of each sample. This
sum divided by the coarse fraction sample weight gave the total percent
of the constituent within the coarse fraction of a sample. An example
of this method is shown in Table 1.

After computing total coarse- fraction percentages of each constit-
uent within all samples, these values were plotted on charts of the bay.
Isolines of percent were then drawn to illustrate the bottom distribu-
tion of the constituents. Figure 5 represents an example of a distri-
bution chart, and it may be interpreted as follows: the area marked
2-10% indicates that the concentration of aggregates and coprolites in
the samples within these boundaries is two to ten percent of the coarse
fraction of the sediments. Similar distribution charts are discussed
in the respective section for each constituent.

Histograms of the number of occurrences of percentage intervals
within each fraction were drawn for every constituent. These are also
discussed in the following sections.

These techniques obviously are sources for errors, the most impor-
tant of which is the visual estimation of the constituent percentage in

12

Table 1
EXAMPLE OF PERCENTAGE COMPUTATIONS

CONSTITUENT: QUARTZ AND FELDSPAR STATION/ SAMPLE NUMBER C-6
LOCATION: LATITUDE 36°41.5'N LONGITUDE 121°55.3'W DEPTH 50 FM.
DRY WEIGHT OF TOTAL SAMPLE 59.07 GM.
DRY WEIGHT OF FINE FRACTION 26.16 GM.
DRY WEIGHT OF COARSE FRACTION 32.91 GM.

CONSTITUENT FRACTION TOTAL WEIGHT OF CONSTITUENT
FRACTION PERCENT WEIGHT WITHIN FRACTION

2 mm. 50 % x 1.61 GM. =

1-2 mm. 35 7, x 1.71 GM. ■

1/2-1 mm. 20 % x 2.13 GM. *

1/4-1/2 mm. 10 % x 2.64 GM. =

1/8-1/4 mm. 40 % x 8.70 GM. -

1/16-1/8 mm. 50 % x 16.12 GM. ■

TOTAL AMOUNT PRESENT IN COARSE FRACTION

CONSTITUENT PERCENT OF COARSE FRACTION

0.8

GM.

0.6

GM.

0.4

GM.

0.3

GM.

3.5

GM.

8.1

GM.

>N 13.7

GM.

f 41.5

GM.

13

each sample. A discussion of error sources is presented in Appendix I.
A breakdown of the composition of all fractions for each sample is
tabulated in Appendix II, showing percentage estimations versus grain
size.

14

DATA ANALYSIS AND INTERPRETATION

Size distribution of sediments

The sediment distribution found as a result of this study is shown
in Figure 4. Contours corresponding to the Wentworth grain-size scale
are illustrated. It may be observed that the boundaries between sand
sizes approximately parallel the shoreline.

The textural distribution is very similar to that reported by Gal-
liher (1932), shown in Figure 2. Significant differences from Galliher's
study, however, are noted in the fact that the greenish very find sands
and silts were found, in the present study, to cover a much larger area,
and that the sediments near the edge of the canyon were found to be
silty sand with a few pebbles rather than the wide strip of "rock gravel"
indicated by Galliher. Only one of Galliher's isolated "rock gravel"
patches was sampled (station G-l), and that was analyzed texturally as
a medium sand. In several samples obtained in the area northwest of Pt.
Pinos, the author found silty sand in the area described by Galliher as
granitic. No granitic pebbles or fragments were found, so that confirm-
ation of a hard rock bottom could not be made; however, granitic out-
crops are abundant in the sea cliffs and surf zone around the peninsula
and one might expect similar outcrops to exist some distance from shore.

Constituent analysis

Discussions of the nine constituents follow, including descriptions
of their appearance and any features of particular interest, their bot-
tom distribution, textural distributions in each sample, influences of
coastal topography and geology, and relationships with other constitu-
ents. These factors contribute to the total sedimentary environment
which has determined the nature of the sediments occurring on the shelf.

15

SEDIMENT DISTRIBUTION

Monterey Submarine /
Canyon

a contour
median
ers.

meters.

Figure 4

16

_ — — — »— ■■ , ■ , yi^»i. <*.:■=«* ■ ■•-■— T»"'- ■

Aggregates and Coprolites

In most bottom samples, aggregates, and to a Lesser degree copro-
lites, consisted of accumulations of fine sand or clay sized grains
cemented together by finer materials. Coprolites, or fecal pellets,
were infrequent in their occurrence and the ones that were observed were
of fairly large size, 1/4 to 1/2 millimeters in diameter, and either
well rounded or tapered at one end. The maximum concentration of copro-
lites never exceeded VL of the combined percentages.

Aggregates were of two general types. Present in lesser amounts
were aggregates consisting of tiny shale particles and other well-
cemented masses of fine material which randomly resisted disaggregation
in the laboratory procedure. Aggregates of mineral grains bound to-
gether by organic material were found in abundance. These were in the
shape of a tiny nest or tube, not larger than one or two millimeters
nor smaller than half a millimeter in diameter, and were composed of an
outer framework of quartz or feldspar grains. Upon first investigation
the walls in the interior, as viewed through the aperture, appeared to
consist of dark brown mica flakes; however, after splitting several open,
it became clear that this internal coating was a dark secretion used by
an organism as a cementing substance for the nest or tube. These common
aggregates were most abundant in the fine sand or silt areas. None of
the organisms were found occupying these tubes. Personal communication
with Dr. E. C. Haderlie, Professor of Biology at Monterey Peninsula
College, confirmed the author's suspicions that these nests were pos-
sibly constructed and utilized by a species of annelid worm which is
common in this area.

Several examples of the aggregates and coprolites found in the

17

samples are pictured in the photograph in Figure 7(a).

The percentage distribution of aggregates and coprolites found in
the southern Monterey Bay is shown in Figure 5. Figure 6 presents a group
of six histograms, each for a given Wentworth size fraction, showing the
number of samples (out of a total of 38) in which the aggregate and copro-
lite concentrations lie in the percentage ranges shown. From these two
illustrations, it is evident that the maximum concentration of aggregates
and coprolites occurs on the outer shelf in the area identified textur-
ally as very fine and fine sandy bottom, and that there is a tendency
for percentages to occur in the larger fractions. The latter conclusion
is confirmed by microscopic observation.

Distance from the coast is obviously an important factor in the con-
centration of aggregates. It is possible that the wide area of wave
action around the peninsula tends to mechanically disintegrate them; on
the other hand, they may have been produced by organisms which avoid this
rigorous environment.

Aggregates themselves do not appear to bear a relationship to any
of the other constituents. Coprolites, on the other hand, have been
tabbed by Cloud (1955), Burst (1958), and later by Shepard (1963), as
one of the possible source materials for the formation of glauconite.
This relationship will be discussed again in the section on glauconite*

18

AGGREGATFS &CQPRQLITFS

Adapted "from

U SC & G S - Chart" 54;Qr3:

V • v

<

• E ' * (C •'

I,

... ;

HISTOGRAMS OF THE NUMBER OF SAMPLES

OF

AGGREGATES & COPROLITES

NBR.
-40-r

( 38 SAMPLES )

™2 20-

■&^

?2 2°'
-2

O
40

2 cm^ 20-

0

0 —

< CM

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^ 72 20,

_I 0

-40'

;:izi

dim

177771

E7777i

Ma

I2 20

«2

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n 0

22_

YZZL

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.S22L

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^

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^ i 177773 ffT^T^

ZZZ2-ZZZ&

2ZZ-:JZZZZ.

-----

vs. . I

' U<tiUi\

JZZZ2-LEZZZ3-L

0 10 20 30 40 50 60 70 80 90 100
' PERCENT WITHIN FRACTION

Figure 6

20

r ■ i i

(a) AGGREGATES & COPROLITES

:

hti i I I I 1 1 f"i'"

(b) BIOTITE

Figure 7.

Biotite

Biotite found in the samples ranges in color from brown to bright
green. The crystals of bright-green color were "inflated" and are evi-
dently what Galliher (1935) was referring to as the transition stage in
the transformation of biotite to glauconite. Examples of biotite found
in the sediment are shown in Figure 7(b).

The distribution chart of biotite, Figure 8, shows a large area of
high concentration lying parallel to and centered about three miles
from the shoreline. This concentration is possibly a result of drain-
age from the Salinas River as an erosion product of metamorphics located
well up in the valley. Minimal amounts of biotite are found in the surf
zone and the nearshore areas. This is very likely the effect of wave
action in tending to keep the flaky grains in suspension and their re-
sultant rafting out into quieter water.

The area of maximum concentration coincides well with the areas
described texturally as very fine sand and silt or clay. This is sig-
nificant in view of the fact that in samples having the greatest percent-
ages of biotite, it is concentrated in the fine and very fine fraction
categories, as may be seen from the histogram in Figure 9. The conclu-
sion can thus be reached that biotite constitutes a major contribution
to the sediments in this area, and that the contribution is mainly in
the fine and very fine sand sizes.

In the role of a rock-forming mineral, biotite is often closely re-
lated in its occurrence to quartz and feldspar. However, the granitics
forming the peninsula contain only small amounts of biotite and it seems
probable that offshore the biotite is derived primarily from metamor-
phics located well inland and introduced mainly by the Salinas River.

22

Because of the marked difference in hydrodynamic properties of biotite
flakes compared with grains of quartz and feldspar, the distribution of
these constituents should not necessarily be expected to be similar. This
is borne out by comparison of Figures 8 and 27.

A discussion of the biotite-glauconite relationship, with regard to
the study made by Galliher (1935), is covered in detail in a later sec-
tion.

23

BIOTITE

Adapted" from U.S.C&:G.S. .Ghact'5403

TN.M. /Txt

2

o

u
<

en
u.

HISTOGRAMS OF THE NUMBER OF" SAMPLES

OF

BIOT ITE

NBR

-40

™2 20-

0

40-

?2 20

— A

<\ii 20-

i

<M

72 20-

^2

■A

s

I2 20

S°2

-&

CO

Tl 20
H 0.

2J

1

^

21

i

1

^

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PERCENT WITHIN FRACTION

I :' '
■ ■ I

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\'i .■'/.■■• i

i ..'■.'..•, ; . ■ l

'■■*/ M

■

i'l

.) '■ • .'

•r>

Figure 9

25

<&•

Foraminifera

Planktonic foraminifera were the dominant type present in all the
samples in which these calcareous organisms were found. The genus most
frequently observed was Globorotalia, with minor occurrences of F label -
linella and Uvigerina. Photographic examples of foraminifera found are
shown in Figure 12(a).

As indicated in the distribution chart shown in Figure 10, foramin-
ifera are a relatively minor constituent in the sediments of the south-
ern bay. The total concentration did not exceed 10% in any sample.
The areas of relatively greater concentration offshore may be a result
of greater productivity, due possibly to upwelling, or to reduced rates
of supply of other constituents in comparison with the rate of supply of
plankton.

Foraminifera have been associated in other investigations with both
glauconite and phosphorite. Burst (1958) and Shepard (1963) suggested
that glauconite might be formed through the conversion of matter filling
foraminifera tests. It is possible, in this region, that foraminifera
tests are commonly destroyed by abrasion or solution so that the concen-
tration of glauconite has increased in proportion to the tests. Another
possibility is that glauconite is indeed formed within foraminifera
tests, but that it is being formed in other ways as well. However,
this origin for glauconite in Monterey Bay appears improbable for the
following reasons:

(1) The concentrations of glauconite are much larger than those of
foraminifera, and the two occupy somewhat different areas of the bottom.

(2) The observed foraminiferal tests were, in the majority, clean
and empty of any material. In those containing a filling, no glauconite

26

or transitional material was found.

From studies of phosphorite oolites and nodules, tests of foramin-
ifera have been identified by Shepard (1963), Dietz, Emery, and Shepard
(1942), and Mero (1960), as a commonly occurring nucleus around which
the mineral phosphorite may be precipitated. The minor amounts of phos-
phorite found in this study were in the form of precipitation coatings
on quartz and feldspar grains, and the relationship with foraminifera in
this area is considered insignificant.

27

FORAM IN I FERA

Adapted "from O&C &:G. S. .CJlar(t".5.403

" 1NM- - HTvik

HISTOGRAMS OP THE NUMBER OF SAMPLES

. OF

FOR AM I NIFERA

NBR
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.' PERCENT WITHIN FRACTION

Figure ' Hi-

29*

* ■ ''■ '•.

• r t.'i

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— luj WWII

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i I

(a) FORAMINIFERA

(b) GLAUCONI TE

Figure 12.

Glauconite

Glauconite grains found in the southern bay sediments during this
study ranged in color from the bright-green mineral to earthy greenish-
brown glauconite pellets. Examples of these grains are shown in the
photograph in Figure 12(b).

The glauconite distribution in the southern bay, shown in Figure
13, is well defined although the percentage concentrations are fairly
small. A center of concentration occurs approximately three miles north
of Pt. Pinos. It appears probable that this area represents a non-
depositional environment such as has been reported in areas off the
southern California coast by Dietz, Emery, and Shepard (1942). An
additional area of higher concentration is pictured to the north near
the canyon edge, which also probably represents a non-depositional sur-
face.

The histogram shown in Figure 14 indicates little tendency for glau-
conite grains to be predominant in any particular grain size. However,
it is interesting to note that the few occurrences of greater percentage
appear in the medium to fine grain sizes where there is also a prepon-
derance of biotite grain sizes.

Glauconite is an abundant constituent of the bottom sediments in
many parts of the world. Its occurrence in Monterey Bay was first re-
ported and investigated by Galliher (1935). He concluded that a chemical
transformation of biotite into glauconite takes place on the continental
shelf within the bay. His conclusions were based on what he described
as a transition from flat brown flaky biotite grains near shore to
bright- green glauconite in deeper water. He described this transition
as being characterized by a transformation stage in which the biotite

31

crystals become inflated, spongy grains of glauconite. Cloud (1955)
upheld Galliher's findings, and further suggested that glauconite is not
found in deep sea sediments because biotite or micaceous minerals come
to rest on the sea floor on the continental shelves. He also suggested
that the widespread distribution of biotite accounts for the common
occurrence of glauconite.

The marine environment within the southern bay appears to be en-
tirely suitable for the formation of glauconite. The minimal supply of
sediments being provided at the present time by the Salinas River and
the small amount of shoreline erosion of the peninsula apparently permit
the non-depositional areas on the shelf that are believed to be needed
for formation. The very fine sand and silt or clay in these areas were
found to be low in oxygen, as indicated by the high concentrations of
organic debris, shell fragments, and foraminifera, accompanied by a
strong odor of H2S.

Four relationships between glauconite and other constituents arise
from the propositions set forth by Burst (1958) for the genesis of glau-
conite. These are as follows:

(1) Chemical alteration of fecal pellets or coprolites

(2) Transformation of materials filling foraminifera tests

(3) Conversion of shale pellets to glauconite

(4) Alteration and transition of biotite into glauconite

As mentioned in the section on aggregates and coprolites, the amount
of fecal pellets was never observed to exceed one percent of the combined
percentage. Since coprolites are so infrequent in their occurrence, it
appears likely that this relationship is not the basis of glauconite
genesis in the area. The same reasoning applies to the theory on the

32

conversion of shale pellets, since they also do not occur in abundance.
The transformation of materials in foraminifera tests has been dismissed
as an important glauconite source in the preceding discussion of forami-
nifera.

Galliher's theory for glauconite genesis by alteration of biotite
is confirmed as the probable formation method in Monterey Bay, since
there appears to be a quantitative relationship between these two con-
stituents in the area as compared to the insignificant relationships be-
tween glauconite and the previously discussed constituents, shale pellets
(aggregates), coprolites, and foraminifera. The relationship of glauco-
nite and biotite is shown quantitatively in Figure 15 as a ratio of the
percentages of the two minerals. This contoured chart delineates nicely
the areas of low glauconite-high biotite concentration, a transition
area where glauconite amounts to a fraction of the biotite concentration,
and finally, a small area where glauconite concentration is, interest-
ingly enough, greater than that of biotite.

In summary, the relative concentration of glauconite is minor; how-
ever, the interesting aspect of its genesis makes it an important sedi-
ment constituent as well as an environmental indicator.

33

GLAUCON I TE

A da.pt e d ' f ro m U S" C & :G S . C ha r f . 5 '403

Figure 13

34 •

,

HISTOGRAMS OF THE NUMBER OF SAMPLES

OF

GLAUCON I TE

o

u
<

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PERCENT WITHIN FRACTION

• .• .

. i I

■■.,,..

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Figure 14

: 35

.-a-

6LAUCQN1TE8 B1QT1 TE

"' } Adapted., from ' ITS G & G s" Cha;rt ' 5403">

■ JO / *" „ " .!■ . »*",■* *'.l

Figure 15

36

Mafics

Ferromagnesian minerals, excluding biotite, make up the majority
of the dark or mafic minerals found in the sediments that were investi-
gated. These include, for the most part, hornblende and pyroxene, with
small amounts of tourmaline, olivine, and epidote also present. The
photograph in Figure 18(a) illustrates a few of the mafic grains ob-
served.

These dark minerals have as their source the granitics of the
peninsula, as well as the granitics and metamorphics from the Salinas
River drainage. The distribution chart in Figure 16 shows generally
what one would expect considering the slightly higher specific gravity
of the mafics. A maximum amount occurs along the coast in the surf
zone and beach sands. The concentrations are generally less offshore,
except for an anomalous area centered to the north of Pt. Pinos.

The histogram of mafic percentages shown in Figure 17 reveals a
wide variation in the number of occurrences within the percentage inter-
vals for each fraction size. There is no evident tendency toward rela-
tive concentration of the mafics in any particular size grouping.

Two relationships that appear important concerning the distribution
of mafics within the area, are the relative concentration of the rock-
forming mafics, as compared to quartz and feldspar, and the relative
concentration of the mafics plus biotite in comparison with quartz and
feldspar. The ratio of mafics to the quartz-feldspar concentration is
illustrated for each station in Figure 19. The distribution is diffi-
cult to interpret. The minor amounts of mafics as compared to quartz
and feldspar in the sediments around the peninsula, outlined by the less
than 0.20 contour, may be due to the origin of the mafics in that area

37

principally from the diorite or granodiorite composition of the penin-
sula granitics in which ferromagnesian minerals are not highly abundant,
If biotite is included with mafics, the relationship between the dark
minerals and quartz and feldspar is shown in Figure 20.

38

MAFICS

Adapted 1 rorn U SC & Q S C.haff \ ;54:0'3"\

*

1NM

\ u

\

histograms of the number of samples i

.of • . ■'■>;■].:] .■;..'

M A F I C S t ',; ■■,}.'

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Figure. 17". ; .' ' }■ ■ \

'40'

•• < . ■ • «

i i

■ .

(a) MAF ICS

(b) PHOSPHORITE
Figure 18.

MAFICSSQUART7&FF! DSPAR

/■ Adapted- from USC &:G S" Chart "5403'

Figure 19

42

MAFICS_»BIOTITF8QUARTZ-FFir>SPAR _

" " 'f Adapted ■ from U S C &:;G S .Chant"540S'-'^

' *» \ U . \

.1 N M V —i

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Figure 20

43

Phosphorite

The discovery of phosphorite off the coast of California was reported
by Dietz, Emery, and Shepard in 1942. In 1950, Emery and Dietz indi-
cated an occurrence of phosphorite within Monterey Bay in the form of
oolites, as a result of their investigation along the California and
Mexico coasts.

Phosphorite, an authigenic mineral precipitated from sea water
directly onto some nucleus, occurs in the form of slabs, nodules,
oolites, and, occasionally, as coatings on foraminiferal tests and sand
grains. The conditions necessary for the precipitation of phosphorite
have been discussed in detail by Dietz, Emery, and Shepard (1942), and
more recently by Mero (1960,1961). The most important of these require-
ments are iterated below:

(1) The environment of precipitation must be non-depositional in
character, or nearly so.

(2) The environment must have reducing characteristics, as a re-
sult of low oxygen content in the immediate vicinity of the precipita-
tion.

(3) The precipitation must take place around some nucleus.

(4) A source of nutrient rich (particularly phosphate) waters must
be available.

The non-depositional nature of the environment and the low oxygen
or reducing characteristics appear to be satisfied and were discussed
in the section concerning glauconite. The presence of nuclei obviously
satisfies the third requirement, and here it should be noted that the
phosphorite that was observed was precipitated as coatings on sand
grains. The presence of nutrient-rich waters, which are brought into

44

the surface layers during the spring and summer by seasonal upwelling,
appears to be one of the prime reasons for expecting phosphorite to
occur abundantly in the area. The Monterey Submarine Canyon very likely
serves to channel upwelled water to the continental shelf from the deep
sea floor.

In spite of the fact that the necessary conditions appear to be
met, the maximum amount of phosphorite found in any sample was less than
one percent. As stated above, the phosphorite found in the samples was
in the form of a precipitate on sand grains. Its composition was con-
firmed by an ammonium molybdate-nitric acid test. Typical examples of
the phosphorite observed are shown in the photograph in Figure 18(b).

The bottom distribution of phosphorite is shown in Figure 21. The
area of concentration coincides fairly well with the high concentration
of organic debris shown in Figure 24. A high concentration of organic
material is conducive to the precipitation of phosphorite for two rea-
sons: first, its presence favors an anaerobic environment which, through
oxidation of the organic material, creates low oxygen in the vicinity.
Secondly, the action of the decomposition process releases phosphate to
the water which is then available for precipitation as phosphorite. The
relation between phosphorite and organic debris is illustrated in Fig-
ure 22 in the form of a ratio between the percentages of phosphorite to
those of organic debris.

Little information can be obtained from the histogram shown in
Figure 23, other than a confirmation that the overall percentage amounts
of phosphorite are low and in the interval of 0-107o. The few grains of
phosphorite observed were in the coarser grain sizes.

45

PHOSPHOR IT E

Adapted " from U S'G &"G S .Chart .5403.

Figure 21

46

PHOSPHOR1TE8QRGAN1C DEBRIS

': /- Adapted .from U SC "8* G: S -Chart J 54-&3-V

HISTOGRAMS OF THE NUMBER OF SAMPLES

OF

PHOSPHOR ITE

Q
o

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0 10 20 30 40 50 60 70 80 90 100
PERCENT WITHIN FRACTION

^ Figure 23 .

48

i

<*•

Organic Debris

This constituent was chosen to include the remainder of the organic
matter present in the samples which could not be grouped under shell frag-
ments and foraminifera. This material consisted largely of unidentified
plant or wood fibers, and other organisms such as diatoms, dinoflagel-
lates, sponge spicules, as well as segments of the appendages of brittle
stars that were commonly found in the samples. Examples of the types of
organic material included in this category are pictured in Figure 26(a).

The plant and wood fibers are probably derived from rivers draining
into the bay; however, kelp beds frequently found on the hard rock bottom
in shallow depths around the peninsula are very likely an additional im-
portant source for the plant fibers. The remaining organics are mainly
the tests of pelagic organisms that have settled to the ocean floor in
the area.

The distribution of organic debris, illustrated in Figure 24, shows
the effects of wave action near shore in preventing these materials from
settling out because of their low density or fine size. It may be noted
that the zone of significant organic content extends into shore in the
sheltered southern end of the bay. The area of maximum concentration
seaward of the mouth of the Salinas River could be the result of debris
introduced by the river, although it is more likely due to the abundance
of benthonic and planktonic organisms constituting the organic debris
in that area. With regard to the general water circulation in the bay,
the tongue of high organic content shown in the figure may trace the
average path of offshore water into the southern end of the bay, with
its high concentration of pelagic organisms.

The size distribution of the organic matter is shown in the

49

histogram In Figure 25, and indicates that the majority of the debris
is concentrated in the medium and coarse sizes.

The only significant relationship to other sediment constituents,
is the relative amount of organic debris found in the areas of phos-
phorite occurrence. This relationship was discussed in the section con-
cerning phosphorite.

50

ORGANIC DEBRIS

Adapt ecffrohn USC.&G:;S eiiart $4©3>

Figure 24

51

HISTOGRAMS OF THE NUMBER OF SAMPLES

OF

ORGANIC DEBRIS

NBR.
40-

Z

o

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^2 20-

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* PERCENT WITHIN FRACTION

Figure 25

52

%

(a) ORGANIC DEBRIS

(b) QUARTZ & FELDSPAR

Figure 26.

Quarts and Feldspar

All light colored minerals in the sediments were grouped together
under the heading of quartz and feldspar. Quartzites are included and the
feldspar crystals were predominately plagioclase. Examples of the mineral
grains included in this category are pictured in Figure 26(b).

These two most common rock- forming minerals occur abundantly through-
out the area, and constitute more than 707. of the extensive beach and dune
sands along the coast. In general, there is a decrease in concentration
with distance from shore, primarily due to the increase in organics.
This distribution is pictured on the chart in Figure 27. The granitics
of the peninsula are obviously a source for these minerals, but the
Salinas River undoubtedly has supplied the most sediment to the bay. The
sand beaches and dunes along the coast of the inner bay probably derived
their sediment from the river source.

The size distribution of the quartz-feldspar constituent is shown in
Figure 28, and points out that the greater percentages, in general, occur
in the finer size fractions.

The relationships between the rock- forming minerals--mafics, biotite,
and quartz-feldspar--were discussed in the section concerning the distri-
bution of mafics in the bay.

54

QUARTZ & FELDSPAR

fed from: U S C.& § S ■ ChaHt".5.4Qr3-

Figure 27

55

HISTOGRAMS OF THE NUMBER OF. SAMPLES

QUARTZ & FELDSPAR

NBR.
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cv]2 20-

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— £

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0 10 20 30 40 50 60 70 80. 90 100
' PERCENT WITHIN FRACTION

Figure 28

56

Shell Fragments

Fragments of shells were found in the sediments in varying amounts
throughout the area; these included gastropods, pelecypods, and other
molluscs. No attempt was made to identify the organisms, since most
found were only fragments or pieces and it would have been difficult in
many cases to determine their characteristics for identification. Sev-
eral examples of these fragments are illustrated in the photograph in
Figure 29.

The distribution of shell fragments is shown in Figure 30, and re-
veals a highly patchy pattern. In samples in which the concentration was
greater than 20%, shells clearly represented a major contribution to the
sediment. There is a relatively small concentration along the coast,
due probably to the effects of wave action and a lack of local supply of
the shells. The area of 10-20% shell fragments immediately north of Pt.
Pinos coincides well with two "shell gravel" locations indicated by Gal-
liher. This may be observed by referring to Figure 2.

The size- frequency distribution of shell fragments, shown in Figure
31, reveals that the greatest percentages of shells are very coarse.

Aside from the obvious connection between shell fragments and other
organic matter, no significant relationship appears to exist between
shell fragments and other constituents in the area.

57

■

V

<

1

1

•><

tops Hi

''? ' -

^&#^A^f- >' * 1

y ,

\

3W

j.
i »w

SHELL FRAGMENTS
Figure 29.

SHELL FRAGMENTS

Adapted "from USC&:;G.S. .Chart. 5403N

Figure 30

59

HISTOGRAMS OF THE NUMBER OF SAMPLES

SHELL FRAGMENTS

NBR.
40

O

o
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U.

<m2 20-

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— &

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0 10 20 30 40 50 60 70 80 90 100
* PERCENT WITHIN FRACTION

Figure 31

60

SUMMARY AND CONCLUSIONS

Controlling factors

In general, the controlling factors of the depositional environments
of southern Monterey Bay are:

(a) The Salinas River drainage which supplies erosion products from
sedimentary, igneous, and metamorphic rocks located in the watershed.

(b) Shoreline erosion of the granitics forming Monterey Peninsula.

(c) The presence of Monterey Submarine Canyon which serves to chan-
nel sediment to the deep sea floor and also acts as a barrier to prevent
the influx of sediment from the north.

(d) Wave action around the peninsula and the marked wave shadow in
the extreme southern end of the bay.

Distribution characteristics

These influences are manifested in the distributions of all nine con-
stituents selected for the area, the principal characteristics of which
are:

(a) The concentrations of constituents tend to form belts roughly
paralleling the shoreline.

(b) Some constituents, such as the rock- forming minerals, quartz-
feldspar, and mafics, tend to occur in highest concentration along the
coast. Others, such as glauconite, phosphorite, and organics tend to
occur in least concentration along the coast.

(c) Another area of distinctive concentration is centered several

miles north of Pt. Pinos, where glauconite, phosphorite, aggregates, and

organics reach their maximum concentrations. This area possibly repre-
sents a non-depositional environment region of relict sediments.

61

(d) An anomalous area in the concentrations occurs in the extreme
southern end of Monterey Bay, where the distribution of constituents is
more representative of that out on the shelf. This is attributed to the
presence of quieter water due to the sheltering effect of the peninsula.

(e) Terrigeneous sediments dominate the southern bay but pelagic
sediments compose as much as 50% of the sediments on the outer shelf.

62

ACKNOWLEDGMENTS

The author wishes to express his appreciation to Prof. Warren C.
Thompson, U. S. Naval Postgraduate School, for his patience and advice
throughout this investigation. An Office of Naval Research Institutional
Grant to Dr. Thompson provided funds for the purchase of much of the
needed laboratory equipment. The initial interest in the sediments of
Monterey Bay was instilled in the writer during a week- long cruise in the
bay aboard the Scripps Institution of Oceanography R. V. HORIZON, working
under Dr. Francis P. Shepard, whose counsel is gratefully acknowledged.
The author also wishes to thank Assoc. Prof. Charles L. Taylor, U. S.
Naval Postgraduate School, for taking the photographs of examples of the
nine constituents, and Mr. Harold Hess, U. S. Bureau of Mines, Marine
Mineral Technology Center, for his advice and for background material and
information on phosphorite and glauconite.

63

BIBLIOGRAPHY

Burst, J. F. Glauconite pellets: Their mineral nature and applications
to stratigraphic interpretations. Bulletin of American Association of
Petroleum Geologists, v. 42, 1958: 310-327.

Cloud, P. E. , Jr. Physical Limits of Glauconite Formation. Bulletin
of American Association of Petroleum Geologists, v. 39, April 1955:
484-492.

Dietz, R. S., Emery, K. 0., and Shepard, F. P. Phosphorite Deposits on
the Sea Floor off Southern California. Geological Society of America
Bulletin, v. 53, 1942: 815-848.

Emery, K. 0., and Dietz, R. S. Submarine Phosphorite Deposits off
California and Mexico. California Journal of Mines and Geology, v. 46,
1950: 7-15.

Galliher, E. W. Sediments of Monterey Bay, California. State Mineralo-
gist of California, Report 28, v. 28, 1932: 42-71.

Galliher, E. W. Glauconite Genesis. Geological Society of America
Bulletin, v. 46, 1935: 1351-1366.

Martin, B. D. Geology of the Monterey Submarine Canyon. Ph. D. Thesis,
University of Southern California, 1963.

Mero, J. L. An Economic Analysis of Mining Deep-Sea Phosphorite. Ph. D.
Thesis, Institute of Marine Resources, University of California, 1960.

Mero, J. L. Sea Floor Phosphorite. California Division of Mines and
Geology, Mineral Information Service Bulletin, v. 14, 1961.

Shepard, F. P., and Moore, D. G. Sedimentary Environments Differentiated
by Coarse Fraction Studies. Bulletin of the American Association of
Petroleum Geologists, v. 38, August 1954: 1792-1802.

Shepard, F. P. Submarine Geology. Harper and Row, 1963.

64

APPENDIX I

SOURCES OF ERROR IN ESTIMATION AND COMPUTATION

OF
CONSTITUENT CONCENTRATIONS

In visual estimation, as pointed out by Shepard and Moore (1954),
the quantity of a constituent in a given grain size fraction of a sedi-
ment sample is best described in terms of a volume percentage rather than
a weight percentage, due to the difficulty of visually estimating weights
in contrast to volumes. Since the total quantity of a fraction is charac-
teristically measured in terms of weight, errors can be introduced by
multiplying volume percentages by weight, because of the differences in
the density of the grains composing the different constituents in the
fraction.

An idea of the magnitude of this error may be approximated in the fol-
lowing manner: by multiplying the estimated volume percent of a constitu-
ent within a size fraction by its specific gravity, a constituent unit
weight may be obtained. Summing these unit weights for all constituents
within the fraction produces a total unit weight. Finally, individual
weight percentages may be computed by dividing constituent unit weights
by the total unit weight. In the following pages, the magnitude of this
error for a randomly selected station, C-10, is shown in the right hand
column labeled "variation." The average variation of the volume percent-
ages from the weight percentages was found to be±l.l% for this sample.

If it is assumed that an error of±57«, may occur in visually estimat-
ing the volume of a constituent in a given size fraction, it is immediately
apparent that this type of error is significantly larger than the volume-
weight conversion error.

65

VOLUME PERCENTAGES COMPARED TO WEIGHT PERCENTAGES FOR SAMPLE C-10
FRACTION: > 2 mm

VOLUME

SPECIFIC

UNIT

WEIGHT

CONSTITUENT

PERCENT

GRAVITY

WEIGHT

PERCENT

VARIATION

QTZ & FLDSPR

5

2.65

13.2

4.9

0.1

BIOTITE

0

3.00

0.0

0.0

0.1

MAFIC S

5

3.30

16.5

6.2

1.2

ORG. DEBRIS

3

1.80

5.4

2.0

1.0

FORAMS

0

2.00

0.0

0.0

0.0

SHELL FRAGS

5

2.00

10.0

3.7

1.3

GLAUCONITE

0

3.00

0.0

0.0

0.0

PHOSPHORITE

2

3.20

6.4

2.4

0.4

AGG & COPRO

80

2.70

TOTAL

216.0
267.5

80.8
100.0%

0.8

100%

FRACTION: 1-2 mm

CONSTITUENT

QTZ & FLDSPR

20

2.65

53.0

19.8

0.2

BIOTITE

0

3.00

0.0

0.0

0.0

MAFIC S

8

3.30

27.4

10.2

2.2

ORG. DEBRIS

3

1.80

5.4

2.0

1.0

FORAMS

0

2.00

0.0

0.0

0.0

SHELL FRAGS

7

2.00

14.0

5.2

1.8

GLAUCONITE

0

3.00

0.0

0.0

0.0

PHOSPHORITE

2

3.20

6.4

2.4

0.4

AGG & COPRO

60

2.70

162.0
TOTAL 268.2

60.4
100.0%

0.4

100%

66

FRACTION: 1/2-1 mm

VOLUME

SPECIFIC

UNIT

WEIGHT

CONSTITUENT

PERCENT

GRAVITY

WEIGHT

PERCENT

VARIATION

QTZ & FLDSPR

25

2.65

66.2

24.5

0.5

BIOTITE

5

3.00

15.0

5.6

0.6

MAFIC S

10

3.30

33.0

12.3

2.3

ORG. DEBRIS

7

1.80

12.6

4.7

2.3

FORAMS

2

2.00

4.0

1.5

0.5

SHELL FRAGS

0

2.00

0.0

0.0

0.0

GLAUCONITE

0

3.00

0.0

0.0

0.0

PHOSPHORITE

1

3.20

3.2

1.2

0.8

AGG & COPRO

50

2.70

135.0

50.2

0.2

100%

TOTAL

269.0

100.0%

FRACTION: 1/4-1/2 mm

CONSTITUENT

QTZ & FLDSPR

40

2.65

106.0

38.3

2.7

BIOTITE

10

3.00

30.0

10.8

0.8

MAFICS

20

3.30

66.0

23.8

3.8

ORG. DEBRIS

4

1.80

7.2

2.6

1.4

FORAMS

2

2.00

4.0

1.4

0.6

SHELL FRAGS

2

2.00

4.0

1.4

0.6

GLAUCONITE

2

3.00

6.0

2.2

0.2

PHOSPHORITE

0

3.20

0.0

0.0

0.0

AGG & COPRO

20

2.70

54.0

19.5

0.5

100%

TOTAL 277.2

100.0%

67

FRACTION 1/8-1/4 mm

CONSTITUENT

VOLUME
PERCENT

SPECIFIC
GRAVITY

UNIT
WEIGHT

100%

TOTAL 280.1

WEIGHT
PERCENT

100.0%

VARIATION

QTZ & FLDSPR

50

2.65

132.5

47.3

2.7

BIOTITE

10

3.00

30.0

10.7

0.7

MAFIC S

15

3.30

49.5

17.7

2.7

ORG. DEBRIS

2

1.80

3.6

1.3

0.7

FORAMS

0

2.00

0.0

0.0

0.0

SHELL FRAGS

3

2.00

6.0

2.1

0.9

GLAUCONITE

5

3.00

15.0

5.4

0.4

PHOSPHORITE

0

3.20

0.0

0.0

0.0

AGG & COPRO

15

2.70

43.5

15.5

0.5

FRACTION: 1/16-1/8 mm

CONSTITUENT

QTZ & FLDSPR

60

2.65

159.0

55.8

4.2

BIOTITE

5

3.00

15.0

5.3

0.3

MAFIC S

25

3.30

82.5

29.0

4.0

ORG. DEBRIS

2

1.80

3.6

1.3

0.3

FORAMS

0

2.00

0.0

0.0

0.0

SHELL FRAGS

1

2.00

2.0

0.7

0.3

GLAUCONITE

2

3.00

6.0

2.1

0.1

PHOSPHORITE

0

3.20

0.0

0.0

0.0

AGG & COPRO

5

2.70

16.5

5.8
100.0%

0.8

100%

TOTAL 284.6

68

APPENDIX II
CONCENTRATION OF CONSTITUENTS IN THE SEDIMENT SAMPLES
(Volume percentage estimates vs. fraction size for each constituent)

SAMPLE NUMBER C-l

COARSE FRACTION PERCENTAGE: 94.57.

CONSTITUENT

> 2mm

2- 1mm

l-l/2mm

1/2

-l/4mm

l/4-l/8mm

1/8

-l/16mm

TOTAL SAMPLE

6

40

33

13

2

1

AGG & COPRO

3

5

8

0

5

2

BIOTITE

0

0

0

3

5

3

FORAMS

0

0

0

9

35

15

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

5

7

5

5

2

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

2

5

5

3

5

3

QTZ & FLDSPR

75

70

70

50

10

60

SHELL FRAGS

20

15

10

30

35

15

SAMPLE NUMBER C-2

COARSE FRACTION PERCENTAGE: 73.6%

CONSTITUENT

TOTAL SAMPLE

10

14

16

7

8

19

AGG & COPRO

60

10

20

80

85

0

BIOTITE

0

0

0

2

5

15

FORAMS

0

0

5

0

0

0

GLAUCONITE

0

0

0

0

0

5

MAFICS

25

30

20

5

5

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

5

5

3

2

2

QTZ & FLDSPR

10

45

40

5

3

65

SHELL FRAGS

5

10

10

5

0

3

69

SAMPLE NUMBER C-3

COARSE FRACTION PERCENTAGE: 36.97.

CONSTITUENT

^2mm

2- 1mm
0

l-l/2mm
0

1/2

-l/4mm
0

l/4-l/8mm
6

1/8

-l/6mm

TOTAL SAMPLE

0

30

AGG & COPRO

25

50

60

60

0

0

BIOTITE

0

0

5

0

15

5

FORAMS

0

5

5

2

5

0

GLAUCONITE

0

0

3

0

15

5

MAFICS

25

5

5

0

20

20

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

10

5

10

0

5

QTZ & FLDSPR

0

10

10

15

40

60

SHELL FRAGS

50

20

7

13

5

5

SAMPLE NUMBER C-4

COARSE FRACTION PERCENTAGE: 86.07.

CONSTITUENT

TOTAL SAMPLE

0

0

0

8

28

49

AGG & COPRO

60

45

25

3

5

0

BIOTITE

0

0

3

20

20

15

FORAMS

0

0

3

0

5

1

GLAUCONITE

0

0

2

0

0

1

MAFICS

5

10

10

3

5

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

5

5

15

0

2

1

QTZ & FLDSPR

10

10

17

70

60

70

SHELL FRAGS

20

30

25

4

3

2

70

SAMPLE NUMBER C-5

COARSE FRACTION PERCENTAGE : 71. 17»

CONSTITUENT

^ 2mm

2- 1mm

l-l/2mm

l/2-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

2

1

7

13

11

36

AGG & COPRO

0

5

15

5

3

2

BIOTITE

0

0

0

5

25

10

FORAMS

0

1

5

0

2

10

GLAUCONITE

0

0

0

3

10

0

MAFICS

50

20

25

30

10

3

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

5

4

5

2

10

5

QTZ & FLDSPR

10

40

40

50

40

65

SHELL FRAGS

35

30

10

5

0

5

SAMPLE NUMBER C-6

COARSE FRACTION PERCENTAGE: 55.5%

CONSTITUENT

TOTAL SAMPLE

3

3

4

5

15

27

AGG & COPRO

40

50

60

70

20

10

BIOTITE

0

0

0

3

10

5

FORAMS

0

0

2

0

0

0

GLAUCONITE

0

0

0

2

3

10

MAFICS

5

10

10

0

20

20

PHOSPHORITE

0

2

0

0

0

0

ORG. DEBRIS

0

0

3

5

2

2

QTZ & FLDSPR

50

35

20

10

40

50

SHELL FRAGS

5

3

5

10

5

3

71

SAMPLE NUMBER C-7

COARSE FRACTION PERCENTAGE: 89.87.

CONSTITUENT

2. 2mm

2- 1mm

l-l/2mm

1/2

-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

0

2

9

6

31

42

AGG & COPRO

0

0

0

5

0

0

BIOTITE

0

0

0

10

5

5

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

5

0

2

MAFICS

0

50

40

30

30

30

PHOSPHORITE

0

5

5

3

0

0

ORG. DEBRIS

0

0

0

10

2

0

QTZ & FLDSPR

0

35

45

35

60

60

SHELL FRAGS

0

10

10

2

3

3

SAMPLE NUMBER C-8

COARSE FRACTION PERCENTAGE: 76.2%

CONSTITUENT

TOTAL SAMPLE

1

1

4

6

20

45

AGG & COPRO

30

40

30

20

0

0

BIOTITE

0

0

0

10

15

10

FORAMS

0

0

30

35

20

0

GLAUCONITE

0

5

5

5

2

0

MAFICS

5

10

5

10

15

20

PHOSPHORITE

0

3

0

0

0

0

ORG. DEBRIS

5

2

5

10

3

5

QTZ & FLDSPR

20

30

20

5

40

60

SHELL FRAGS

40

10

5

5

5

5

72

SAMPLE NUMBER C-9

COARSE FRACTION PERCENTAGE: 2.67.

CONSTITUENT

«> 2mm

2- 1mm

l-l/2mm

l/2-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

0

0

0

1

1

1

AGG & COPRO

0

20

70

65

40

20

BIOTITE

0

0

0

0

20

55

FORAMS

0

0

10

5

0

0

GLAUCONITE

0

5

0

0

0

3

MAFIC S

0

10

0

5

10

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

5

5

20

20

7

QTZ & FLDSPR

0

20

10

5

5

5

SHELL FRAGS

0

40

5

0

5

0

SAMPLE NUMBER C-10

COARSE FRACTION PERCENTAGE: 56.87.

CONSTITUENT

TOTAL SAMPLE

0

1

3

7

16

29

AGG & COPRO

80

60

50

20

15

5

BIOTITE

0

0

5

10

10

5

FORAMS

0

0

2

2

0

0

GLAUCONITE

0

0

0

2

5

2

MAFIC S

5

8

10

20

15

25

PHOSPHORITE

2

2

1

0

0

0

ORG. DEBRIS

3

3

7

3

2

2

QTZ & FLDSPR

5

20

25

40

50

60

SHELL FRAGS

5

7

0

2

3

1

73

SAMPLE NUMBER G-l

COARSE FRACTION PERCENTAGE : 94 . 3%

CONSTITUENT

> 2mm

2- 1mm
0

l-l/2mm
3

1/4-

-l/4mra
48

l/4-l/8mm
32

l/8-l/16mm

TOTAL SAMPLE

0

11

AGG & COPRO

0

30

10

3

0

0

BIOTITE

0

0

0

3

4

5

FORAMS

0

0

2

5

3

5

GLAUCONITE

0

0

0

0

0

0

MAFIC S

0

10

25

20

10

5

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

10

3

5

3

2

QTZ & FLDSPR

0

20

50

60

80

80

SHELL FRAGS

100

30

10

4

0

3

SAMPLE NUMBER G-2

COARSE FRACTION PERCENTAGE: 94.1%

CONSTITUENT

TOTAL SAMPLE

0

AGG & COPRO

0

BIOTITE

0

FORAMS

0

GLAUCONITE

0

MAFIC S

0

PHOSPHORITE

0

ORG. DEBRIS

0

QTZ & FLDSPR

0

SHELL FRAGS

100

0

2

5

5

0

5

2

5

0

0

5

5

0

0

3

0

25

50

60

30

17
5

15
0
0
5
0
5

60

10

52
0

20
5
0

10
0
5

50

10

22
0

10
7
0
0
0
3

70

10

74

SAMPLE NUMBER G-3

COARSE FRACTION PERCENTAGE: 91.0%

CONSTITUENT

^ 2mm

2- 1mm

1

l-l/2ram

1

1/2

-l/4mm
3

l/4-l/8mm
25

1/8

-l/16mm

TOTAL SAMPLE

1

61

AGG & COPRO

0

40

40

15

0

0

BIOTITE

0

0

3

30

20

10

FORAMS

0

5

0

20

2

0

GLAUCONITE

0

0

2

0

0

0

MAFIC S

0

15

0

2

0

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

5

5

10

3

5

QTZ & FLDSPR

0

30

20

20

70

80

SHELL FRAGS

100

5

30

3

5

5

SAMPLE NUMBER G-4

COARSE FRACTION PERCENTAGE: 67.2%

CONSTITUENT

TOTAL SAMPLE

1

3

8

14

13

28

AGG & COPRO

3

7

3

0

0

2

BIOTITE

0

0

1

1

8

7

FORAMS

0

0

3

5

7

2

GLAUCONITE

0

3

3

7

15

10

MAFICS

20

25

30

30

30

5

PHOSPHORITE

0

0

0

1

0

0

ORG. DEBRIS

2

5

5

4

5

1

QTZ & FLDSPR

5

40

50

50

30

70

SHELL FRAGS

70

20

5

2

5

3

75

SAMPLE NUMBER G-5

COARSE FRACTION PERCENTAGE : 77.1%

CONSTITUENT

^ 2mm

2- 1mm
6

l-l/2mm
11

1/2

-l/4mm
10

l/4-l/8mm
13

1/8

-l/16mm

TOTAL SAMPLE

12

26

AGG & COPRO

95

70

40

60

20

5

BIOTITE

0

0

0

0

5

15

FORAMS

0

0

0

2

3

0

GLAUCONITE

0

0

0

1

2

0

MAFIC S

0

5

7

10

5

20

PHOSPHORITE

0

1

1

2

0

0

ORG. DEBRIS

0

0

2

3

10

5

QTZ & FLDSPR

0

20

50

20

50

50

SHELL FRAGS

5

4

0

2

5

5

SAMPLE NUMBER G-6

COARSE FRACTION PERCENTAGE: 98.0%

CONSTITUENT

TOTAL SAMPLE

1

1

2

30

56

8

AGG & COPRO

5

60

40

0

0

0

BIOTITE

0

0

0

0

2

3

FORAMS

0

0

2

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

5

5

15

10

20

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

5

5

3

5

5

0

QTZ & FLDSPR

20

10

25

75

80

75

SHELL FRAGS

70

20

25

5

3

2

76

SAMPLE NUMBER G-7

COARSE FRACTION PERCENTAGE: 96.57.

CONSTITUENT

^2mm

2- 1mm

l-l/2mm

l/2-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

0

0

2

20

51

23

AGG & COPRO

60

60

40

0

0

0

BIOTITE

0

0

0

5

5

15

FORAMS

0

0

0

3

0

0

GLAUCONITE

0

0

0

2

0

0

MAFICS

0

0

10

30

35

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

0

0

0

QTZ & FLDSPR

40

35

40

60

50

70

SHELL FRAGS

0

5

10

0

10

5

SAMPLE NUMBER G-8

COARSE FRACTION PERCENTAGE: 95.27.

CONSTITUENT

TOTAL SAMPLE

0

1

1

2

53

39

AGG & COPRO

100

80

70

40

5

0

BIOTITE

0

0

10

5

5

5

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

10

2

5

25

20

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

5

0

0

QTZ & FLDSPR

0

10

8

40

60

70

SHELL FRAGS

0

0

10

5

5

5

77

SAMPLE NUMBER G-9

COARSE FRACTION PERCENTAGE; 88.9%

CONSTITUENT

> 2mm

2- 1mm

l-l/2ram

1/4

-l/4mm

l/4-l/8mm

l/8-l/16nnn

TOTAL SAMPLE

1

0

1

1

25

61

AGG & COPRO

80

60

50

30

0

0

BIOTITE

0

0

0

20

20

15

FORAMS

0

0

10

5

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

5

7

5

15

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

3

20

0

0

QTZ & FLDSPR

0

25

10

10

60

70

SHELL FRAGS

20

10

20

10

5

5

SAMPLE NUMBER G-10

COARSE FRACTION PERCENTAGE: 97.2%

CONSTITUENT

TOTAL SAMPLE

1

3

4

21

54

15

AGG & COPRO

0

30

20

0

0

0

BIOTITE

0

0

0

5

5

5

FORAMS

0

0

0

15

0

0

GLAUCONITE

0

0

0

2

0

0

MAFICS

0

0

5

5

5

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

10

10

3

5

5

QTZ & FLDSPR

100

20

10

50

70

80

SHELL FRAGS

0

40

55

20

15

10

78

SAMPLE NUMBER G-ll

COARSE FRACTION PERCENTAGE: 64.6%

CONSTITUENT

> 2mm

2- 1mm

l-l/2mm

1/4

-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

6

2

1

2

5

49

AGG & COPRO

10

70

45

50

60

0

BIOTITE

0

0

5

0

20

10

FORAMS

0

0

5

5

0

0

GLAUCONITE

0

0

0

3

0

0

MAFIC S

10

5

10

10

5

10

PHOSPHORITE

0

0

0

2

0

0

ORG. DEBRIS

0

5

5

5

3

0

QTZ & FLDSPR

30

15

20

15

10

75

SHELL FRAGS

50

5

10

10

2

5

SAMPLE NUMBER G-12

COARSE FRACTION PERCENTAGE: 97.27.

CONSTITUENT

TOTAL SAMPLE

0

2

0

14

59

22

AGG & COPRO

0

20

20

5

0

0

BIOTITE

0

0

1

10

10

5

FORAMS

0

0

2

5

5

3

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

5

5

7

2

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

5

2

5

3

5

QTZ & FLDSPR

0

25

30

50

70

80

SHELL FRAGS

0

50

40

20

5

5

79

SAMPLE NUMBER G-13

COARSE FRACTION PERCENTAGE : 96.4%

CONSTITUENT

> 2mm

2- 1mm

1

1-1/ 2mm
2

1/4

-l/4mm
15

l/4-l/8mm
59

1/8

-l/16mm

TOTAL SAMPLE

0

20

AGG & COPRO

0

20

10

7

4

2

BIOTITE

0

0

0

8

7

5

FORAMS

0

5

5

5

8

3

GLAUCONITE

0

0

0

0

1

0

MAFICS

0

0

5

10

15

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

5

10

10

5

10

QTZ & FLDSPR

0

60

50

40

50

60

SHELL FRAGS

0

10

20

20

10

10

SAMPLE NUMBER G-14

COARSE FRACTION PERCENTAGE: 1007.

CONSTITUENT

TOTAL SAMPLE

0

9

67

22

2

0

AGG & COPRO

0

0

0

0

0

0

BIOTITE

0

0

0

0

5

0

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

15

20

20

30

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

0

0

0

QTZ & FLDSPR

0

85

80

75

60

0

SHELL FRAGS

0

0

0

5

5

0

80

SAMPLE NUMBER G-15

COARSE FRACTION PERCENTAGE: 91.67.

CONSTITUENT

>2mm

2- 1mm

1-1/ 2mm

1/2.

-l/4mm

l/4-l/8mm

1/8-

•l/16mm

TOTAL SAMPLE

0

0

10

71

10

0

AGG & COPRO

0

0

0

0

0

0

BIOTITE

0

0

0

2

5

0

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFIC S

0

0

15

20

25

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

0

0

0

QTZ & FLDSPR

0

100

80

75

70

0

SHELL FRAGS

0

0

5

3

0

0

SAMPLE NUMBER G-16

COARSE FRACTION PERCENTAGE: 100%

CONSTITUENT

TOTAL SAMPLE

0

1

3

35

61

0

AGG & COPRO

0

0

0

0

0

0

BIOTITE

0

0

10

5

5

20

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

15

15

10

50

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

0

0

0

QTZ 6c FLDSPR

0

100

75

80

85

30

SHELL FRAGS

0

0

0

0

0

0

81

SAMPLE NUMBER G-17

COARSE FRACTION PERC ENTAGE : 98 . 47.

CONSTITUENT

^ 2mm

2- 1mm
4

l-l/2mm
78

1/4-

-l/4mm
14

l/4-l/8mm
1

1/8-

•l/16ram

TOTAL SAMPLE

3

0

AGG & COPRO

10

5

0

0

0

0

BIOTITE

0

0

0

5

5

0

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFIC S

5

15

30

15

10

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

0

5

0

QTZ & FLDSPR

85

80

70

80

75

0

SHELL FRAGS

0

0

0

0

5

0

SAMPLE NUMBER G-18

COARSE FRACTION PERCENTAGE: 100%

CONSTITUENT

TOTAL SAMPLE

0

2

79

18

1

0

AGG & COPRO

0

0

0

0

0

0

BIOTITE

0

10

0

10

5

0

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

10

5

5

10

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

0

0

0

0

QTZ & FLDSPR

25

65

85

85

80

0

SHELL FRAGS

75

15

10

0

5

0

82

SAMPLE NUMBER G-19

COARSE FRACTION PERCENTAGE: 54.8%

CONSTITUENT

5. 2mm

2- 1mm

1-1/ 2mm

l/4-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

0

1

1

2

9

42

AGG & COPRO

10

60

50

40

10

0

BIOTITE

0

0

0

5

40

25

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

10

15

10

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

90

25

20

20

10

10

QTZ & FLDSPR

0

10

15

10

10

50

SHELL FRAGS

0

5

5

10

20

5

SAMPLE NUMBER G-20

COARSE FRACTION PERCENTAGE: 52.8%

CONSTITUENT

TOTAL SAMPLE

0

0

1

2

8

41

AGG & COPRO

0

10

35

40

20

0

BIOTITE

0

0

0

0

30

15

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

10

10

5

20

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

100

60

35

20

30

10

QTZ & FLDSPR

0

20

10

10

5

50

SHELL FRAGS

0

10

10

20

10

5

83

SAMPLE NUMBER G-21

COARSE FRACTION PERCENTAGE: 11.0%

CONSTITUENT

& 2mm

2- 1mm

l-l/2mm

l/2-l/4ram

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

-

-

-

-

-

-

AGG & COPRO

0

0

20

30

30

5

BIOTITE

0

0

0

0

10

15

FORAMS

0

0

10

10

5

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

5

5

5

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

100

30

40

40

10

QTZ & FLDSPR

0

0

15

5

5

50

SHELL FRAGS

100

0

20

10

5

10

SAMPLE NUMBER G-22

COARSE FRACTION PERCENTAGE: 78.2%

CONSTITUENT

TOTAL SAMPLE

0

0

1

1

7

70

AGG & COPRO

0

0

50

30

0

0

BIOTITE

0

0

0

20

60

5

FORAMS

0

0

0

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

0

0

5

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

100

0

0

0

10

5

QTZ & FLDSPR

0

0

10

10

10

75

SHELL FRAGS

0

100

40

40

15

5

84

SAMPLE NUMBER G-23

COARSE FRACTION PERCENTAGE: 65.47.

CONSTITUENT

> 2mm

2- 1mm
0

1-1/ 2mm
0

1/4

-l/4mm
0

l/4-l/8mm
6

l/8-l/16mm

TOTAL SAMPLE

0

61

AGG & COPRO

0

0

15

20

0

0

BIOTITE

0

0

0

5

40

5

FORAMS

0

0

5

0

0

0

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

10

0

5

10

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

50

10

10

5

0

QTZ & FLDSPR

0

50

20

5

30

80

SHELL FRAGS

0

0

40

60

20

5

SAMPLE NUMBER G-24
CONSTITUENT
TOTAL SAMPLE

AGG & COPRO 10

BIOTITE 0

FORAMS 0

GLAUCONITE 0

MAFICS 0

PHOSPHORITE 0

ORG. DEBRIS 0

QTZ & FLDSPR 0

SHELL FRAGS 90

COARSE FRACTION PERCENTAGE: 11.5%

50

45

0

5

0

0

0

0

0

0

0

0

20

20

0

10

30

20

40

0

0

0

5

0

30

10

15

40
20
0
0
0
0
30
5
5

0

30

0

0

10

0

5

50

5

85

SAMPLE NUMBER G-25

COARSE FRACTION PERCENTAGE : 53.9%

CONSTITUENT

> 2mm

2- 1mm
2

l-l/2mm
3

1/2

-l/4mm
5

l/4-l/8ram
14

l/8-l/16nm

TOTAL SAMPLE

0

29

AGG & COPRO

30

20

15

30

5

0

BIOTITE

0

0

0

0

10

5

FORAMS

0

0

0

5

5

0

GLAUCONITE

0

0

5

5

10

0

MAFICS

0

20

20

10

10

20

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

20

0

5

10

10

5

QTZ & FLDSPR

50

60

50

40

40

70

SHELL FRAGS

0

0

5

0

10

0

SAMPLE NUMBER G-26
CONSTITUENT
TOTAL SAMPLE

AGG & COPRO 20

BIOTITE 0

FORAMS 0

GLAUCONITW 0

MAFICS 40

PHOSPHORITE 0

ORG. DEBRIS 0

QTZ & FLDSPR 40

SHELL FRAGS 0

COARSE FRACTION PERCENTAGE: 44.0%

10

0

0

0

0

10

0

10

40

20

0

0

0

20

50

40

0

0

20

0

10

20

10

0

5

30

5

5
20

5

5
15

0
10
30
10

0

15

0

0

15

0

0

70

0

86

SAMPLE NUMBER G-27

COARSE FRACTION PERCENTAGE: 3.9%

CONSTITUENT

>2mra

2-lram

l-l/2mm

l/2-l/4mm

l/4-l/8mm

l/8-l/16mm

TOTAL SAMPLE

-

-

AGG & COPRO

0

100

70

45

40

0

BIOTITE

0

0

0

0

0

40

FORAMS

0

0

0

20

15

5

GLAUCONITE

0

0

0

0

0

0

MAFICS

0

0

0

5

5

0

PHOSPHORITE

0

0

0

0

0

0

ORG. DEBRIS

0

0

10

25

30

40

QTZ 6c FLDSPR

0

0

0

5

10

10

SHELL FRAGS

0

0

20

0

0

5

SAMPLE NUMBER G-28

COARSE FRACTION PERCENTAGE: 1.7%

CONSTITUENT

TOTAL SAMPLE

-

AGG & COPRO

0

BIOTITE

0

FORAMS

0

GLAUCONITE

0

MAFICS

0

PHOSPHORITE

0

ORG. DEBRIS

0

QTZ & FLDSPR

0

SHELL FRAGS

100

50

70

0

0

0

0

0

0

0

0

0

0

50

5

0

10

0

15

40
0

25
0

5

0

15

10

5

40
0
5
0
5
0
40
10
0

10

40

0

0

5

0

30

10

5

87

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3 JUL 69

Thesis
M683

/

D I !l D L R Y
D I II D El

1 5 5 3 5
16 8 1

1 6 8 4 ?

1 ■*

Monteath ^ »
Environmental analy-
sis of the sediments
of southern Monterey
Bay, California.

I Thesis
M683

Monteath

Environmental analy-
sis of the sediments
of southern Monterey
Bay, California.

C t L 9

'