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THESIS

This is to certilg that the

thesis entitled

3EDII‘JLWTARY FABRICS IN 'UNCONJOLIDATED slums
presented hg

Henry C. Smith, Jr.

has been accepted towards fulfillment

' 0f the requirements for

M.S. Geology

degree in

w Qt

Major professor

'P 9“
Date June 16, 195‘

 

0-169

 

 

up. "a u 1,—-.’.

 

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SEDIMENTARY FABRICS IN

UNCONSOLIDATED SANDS

13:
Henry Carl Smith, Jr.

A THESIS

Submitted to the school of Graduate Studies of Michigan
State College of Agriculture and Applied Science
in partial fulfillment of the requirements

for the degree of
MASflER OF SCIENCE
Department of Geology and Geography

1952

THESIS

.ll||ll If

 

/)-/-/’S‘L

so

11

ACKNOWLEDGMENTS

The writer wishes to express his sincere appreciation to Dr. J.
W. Tree for his many helpful suggestions and criticisms in the direction
of the problem.

The writer is also deeply indebted to Dr. Miriam S. Lucas, of the
Biological Science Department, for her aid and advice in the construc-
tion of the plastic hemisphere.

Grateful achewledgnent is also due to Dr. S. G. Bergquist for
his assistance in the preparation of the manuscript and to Drs. I. A.

Kelly and B. T. Sandefur for their cooperation and loan of various items

of equipent.

Dr) K" "h. (—
,-. 3., ‘ . r,
‘1'” film“? T

LIST OF PLATES . . . . . .
LIST OF FIGURES . . . . .

INTRODUCTION . . . . . . .

TABLE

PURPOSE OF THE INVESTIGATION

METHODS OF PLOTTING POINTS
THREE—AXIS UNIVERSAL STAGE
Description . . . .
Calibration . . . .
Operation . . . . .
Construction . . .

SAMEIIJG . C . O O O O . .
Pill-p083 e

Equipment

Procedure . . . . .

O
O
O
O
0

ANALYSIS OF SAMPLE DATA .
General Explanation
Beach.Sample . . .
Current Ripple-mark
Wind Ripple-mark .

Oscillation or Wave

OF CONTENTS

Ripple-mark . . .

CONCLUS I on C O O O O O O O 0 O O O O O O O O

BIBLIOGMY . O O O O O O O O O O O O O O O

iii

iv

Nmmmmw

10
10
11
11
11
12
in
11+
in
15
18
22
29
3O

iv

LIST OF PLATES

Plate P360
1. Three-axis Universal Stage, Disassembled . . . . . . . . 8
II. Operation of Three-axis Universal Stage . . . . . . . . . 9
13

III. sapliw Equiment O O O O O O O O O O O C 0 O O O O O O

Figure
l.

3.
it.
5.
6.
7.

9.
10.
11.
12.
13.
in.
15.
16.
17.
18.

. 19.

21.

LIST OF FIGURES

Comparison of Long Dimension Elongation and
Least Projection Elongation . . . . . . .

MmMHOJBCtionnue e e e e e e e e e
DeachSample,l_d_Fabric. . . . . . . . . .

BMCh Sample, m.p.a. Fabric e e e e e e e 0

Cross Section and Top View of Current Ripple Mark

Current Ripple Mark, pg. Fabric (A to B) . .
Current Ripple Mark, m.p.a. Fabric (1 to B)
Current Ripple Mark, I; Fabric (3 to C) . .
Current Ripple Mark, m.p.a. Fabric (13 to C)
Current Ripple Mark, EFabric (C to D) . .
Current Ripple Mark, m.p.a. Fabric (C to D)
Wind Ripple Mark Cross Section . . . . . .
Oscillation Ripple Mark Cross Section . . .
Find Ripple Mark, I; Fabric (A to B) . . .

Wind Ripple Mark, m.p.a. Fabric (1 to B)

Wind Ripple Mark, m.p.a. Fabric (B to c) .
Wind Ripple Mark, _l_d Fabric (B to C) . . .

Oscillation Ripple Mark, l_d_ Fabric (1 to B)

Oscillation Ripple Mark, m.p.a. Fabric (A to 3)

Oscillation Ripple Mark, m.p.a. Fabric (3 to C)

Oscillation Ripple Mark, 19‘. Fabric (3 to c) . .

16
16
17
19
19

20
21

2h
2.“

{ii-Oi

26
26
27
37

93

INTRODUCTION

Very little petrofabric work has been attempted on sediments and
sedimentary rocks in comparison with that already accomplished in the
study of igneous and metamorphic rocks. This is largely because in the
latter two fields, the investigations are concerned with crystallographic
‘ elements such as optic axes, poles to cleavage and twinning planes while
in sediments, the interest is in the physical directions of the individ-
ual grains.

Crystallographic elements can be determined and their directions
measured by means of a petrographic microscope equipped with a universal
stage, but determining the physical directions of individual clastic
grains has proven somewhat more difficult.

The two most important physical dimensions of a grain are the
longest direction (1;), and the maximum projection area (m.p.a.). In
the following diagrams, those showing the long dimension actually rep-

resent the “leAstrojection elongation” of Dapples.’

 

*Dapples, E. C., and Reminger, J. 1., Orientation Analysis of Fine-

grained Clastic Sediments: Journal 93: Geolog, Vol. 53, 1916, p. 251.

 

He has defined this elongation direction as that of two parallel
lines with the minimim amount of separation that can be dravn tangent
to the grain (Figure I).

The maximum projection area is explained by Krumbein' as the plane

 

I"Krumbein, W. 0., Preferred Orientation of Pebbles in Sedimentary De-

posits: Journal of Geology, Vol. ‘47, 1939, p. 677.

Al

 

A

Long Dimension Elongation Least Projection Elongation
A-N s—a

Figure 1. Comparison of Long Dimension Elongation and Least Projection Elongation

 

 

Pole to
maximum . 0
projection 4
area i

yplane of
the maximum
. i“‘r-a..

projection area

 

 

 

 

 

 

Top- View - Side View

Figure 2. Maximum.Projection Area

defined by the longest and intermediate diameter of the grain. The
position of this area can be located by the co-ordinatss of a pole per-
pendicular to the surface of this plane.

Krumbein"I and others have demonstrated that it is possible to

 

*Ibid. . pp. 673-706.

 

prepare orientation diagrams when the particles were large enough to be
sampled individually, but this, of course, is not possible with items
as small as sand grains.

Dapples't‘ found definite orientation in a given plane and prepared

 

*Dapples, E. C., and Rominger, J. F., op. cit., pp. 216-261.

 

two-dimensional fabric diagrams. Shortly afterwards Rowland't developed

 

*Rowland, R. 1., Grain-shape Fabrics of Clastic Quartz: Geologifl

Society 9; America Bulletin, Vol. 57, 19%, pp. $7-561»

 

a technique for preparing orientation diagrams of fine-grained clastic
sediments in three dimensions. He determined statistically the angular
relationship between the optic axis of quartz grains and their physical
dimensions and used this data to construct grain—shape diagrams from
optic axis diagrams.

The most recent published improvement in sedimentary petrofabrics

was developed by Schwarzacher'!I who successfully constructed grain-shape

 

*Schwarzacher, L, Grain Orientation in Sands and Sandstones: M

o_f_ Sedimentary Petrolog, Vol 21, 1951, pp. 162-172.

 

diagrams with a binocular microscope and a two-axis universal stage.
With this method the grain's lg_was brought to a horizontal NLS position
using the N—S hair of the binocular as a reference line. The azimuth
and dip of the grain‘s original position was determined by reading the
angles on the universal stage and these values were plotted in the con-
ventional 'Sdhmidt' equal-area net. The stereoscopic view obtained with
the binocular gave a sufficiently accurate estimation of both horizontal
and vertical directions and the author was able to produce definite
orientations with forms of wind and.water deposition'under experimental

conditions.

PURPOSE OF THE INVESTIGATION

The purposes of this study are as follows:

1. To investigate the possibility of shortening and improving
the procedure used in sedimentary petrofabric work without
a corresponding loss in accuracy.

2. To devise a satisfactory method of collecting permanent oriented
samples of unconsolidated sands.

3. To test these methods in an effort to determine the effects of
various components of a natural environment on small sedimentary

features.

METHODS OF PLOTTING POINTS

Petrofabric diagrams are conventionally produced by means of the
”Schmidt“ equal-area not which represents the inside of the lower one-
half of a sphere. Azimuth or strike is read from the periphery and the
dip is determined by the distance from the edge of the circle. A point
at the center of the hemisphere represents a vertical line mails one
located near the outer edge shows the line to be nearly horizontal.
Any line or plane can be plotted on the net in two steps. First the
proper azimuth is found on the periphery and this point is rotated to
either the 90 or the 180 degree position where the dip or plunge can be
marked off to give the true position of the plane or line.

As it was only necessary to plot lines and not planes, equiareal
polar co-ordinate paper was substituted for the "Schmidt” net in the
diagrams prepared for this problem. This method proved somewhat faster

and its use has been discussed more fully by Krumbein.’

 

.Krumbgin. we as. op. Cite. pp. 681-682e

 

THREE-AXIS UNIVERSAL STAG]

Description
Even with the use of a binocular, petrofabric diaaams are te-

dious and lengthy to prepare and these are limiting factors in their
general usefulness. All of the following petrofabric diagrams were
prepared with the aid of a simplified universal stage.

This instrument consists of the following three parts as shown

in Plate I.

l. Six-inch.hollow plastic hemisphere ruled at five degree
intervals with a vertical center post flattened on one side.

2. Plastic sample stage with two magnets, spring clip and a
simplified.mechanical stage.

3. Circular plastic ring base with four reference points
(N, S, O, and E) and three reference arms.

Specimens to be examined were glued to their metal sample slides
(Plates I and II) and the slides were held to the stage by the two magb
nets fastened underneath the stage platform. To facilitate the movement
of the sample, a small mechanical stage (Plates I and II) was added and
this allowed both N-S and 3-! traverses. The stage fitted on the center
post of the hemisphere and was held at any desired elevation by the fric-
tion of the steel spring on the flattened center post. The hemisphere

merely rested in the plastic ring base and was movable in.any direction.

Calibration '

The instrument was calibrated by adjusting the hemisphere so that
zero degrees azimuth coincided with point "N", 90° with point “UP, 1800
with point 'S', and the center with point I'0". Then the binocular was
moved so that the center of the field was directly over a center point
marked on the stage and the use crosshair paralleled a.N;S line of the
stage. The instrument was then ready for use except for occasional ver-
tical adjustments of the stage to allow for variable sample thickness.
Any grain near the center of the field at the proper elevation was at

the center of the hemisphere and could be observed even when rotated 70

degrees in a vertical direction.

uoHnEomeamHe .owapm assuage one u Shayna. H mafia

 

‘-_.._y‘ -_/- , -- _

 

v—~— -

 

PLATE II Operation of the three-axis universal stage

10

Operation (£1352 IL)

Once a sample was adjusted on the stage, a grain was brought
into position under the crosshairs so that its long dimension paralleled
the N—S “crosshair and its m.p.a. was perpendicular to the microscope axis.
The original position of the grain was then determined by observing the
position of the reference points through the transparent hemisphere.
The position of the long-dimension was found at either "N" or "S", depend-
ing on whether the grain dipped north or south. The m.p.a. was located
at not which is 90° from both "it! and Is" and directly in line with the
axis of the binocular.

With steeply dipping grains the procedure was reversed; the l_d
was brought to the vertical position and plotted at '0' while the m.p.a.
was found at either "a" or ”S“. Occasionally a grain was encountered
with both l_d and m.p.a. almost horizontal. In this case the long-dimen-
sion of the grain was» made to parallel the E-w crosshair, the l_d was

located at point 'E" and the m.p.a. at either 9N” or 'S".

Construction

With the exception of thehemisphere, the instrument was made of
readily obtainable sheet and tubular plastic. The details of construc-

tion may be observed in Plate II. The hemisphere 'was molded from liquid

casting plastic sold by the Castolite Company of Woodstock, Illinois or
Ward's Natural Science Establishment of Rochester, New York.

The mold was constructed from plaster of Paris. An ordinary six-
inch rubber ball was used as a (form for the outer mold and was cut in

half when used as a form for the inner mold. To prevent the penetration

ll
of the plaster by the liquid plastic, the mold was sprayed with a thin
solution of Molding Compound No. lOO99-A.made by American Anode, Incor-
porated, of Akron, Ohio. Lines of ordinary India ink were ruled on the
hemisphere with.the‘aid of a curved ruler and drawing compass and these

were protected by several coats of lacquer.

SAMPLING

1322222.
Sandstones capable of having their surfaces ranghened so that the

individual grains can readily be observed.under a binocular are fairly
common, but the petrofabric diagrams prepared from.such specimens are

of little if any interpretive value. Samples prepared experimentally
are excellent for interpretation, but these can hardly duplicate natural
conditions of sedimentation. For these reasons it was decided to cons
fine the following limited investigation of sedimentary fabrics to recent
unconsolidated sands ihere the effects of the natural environment could
be observed and recorded. Of the four specimens examined, the beach
sample and both the wind'and current ripple-marks were collected in the
field while the oscillation ripple-mark was formed under experimental

conditions.

Eguippent (Plate III)
Several types of impregnating materials were tried and the follow»

ing two plastics were found to be most satisfactory for consolidating
incoherent sands into samples suitable for use under a binocular: A five

percent solution of either vinylite VYHH plastic or cellulose acetate and

12

acetone gave equally good results. A complete account of the use of

these materials is given by Smith."I

 

*Smith, R. W., and Maudie, C. D., Collection and Preservation of Soil

Profiles: Soil Science, Vol. 6h, 19?], pp. 61-67.

 

These mterials are almost invisible in the hand specimen and
show only as a thin coating over the individual grains under the bi-
nocular. Additional equipment consisted of a small hand spray gun, an
eyedropper, several 2 x 2 inch squares of thin metal and sample contain—-

are made by cutting cans in half and sharpening the cut edges.

Procedure

The sharpened cans were first pressed down to a depth of one to
two inches in the area to be sampled. The spray gun was used to apply
a thin coat of plastickover the enclosed area. Once this protective
coating was applied, additional plastic was carefully flowed on with an
eyedropper until the sample was saturated. The sample was then oriented,
an area was cleared to one side and the thin supporting metal square was
slipped under both the can and impregnated sand.

The proper percentage of plastic in the solution was found to be
dependent upon both grain size and the amount of moisture present. For
any particular sample the percentage was best determined by experiment-
ation. The time required to harden is also variable and depends upon
sample size, grain size and moisture. The samples should be handled with
care for at least twenty-four hours after collection.

After the specimens were completely hardened, they were removed

from the cans and cut to the required size with a fine-bladed coping saw.

engages 339:8

HHH Ban...

 

‘-"

“qr..-

ANALYSIS OF SAMPLE DATA

General Explanation

In each of the following petrofabric diagrams, the contours show
the percentage density of 200 points which represent the orientation con-
centrations of either the long dimension or the maximum projection area
of 200 sand grains.

All the diagrams have been rotated to a horizontal plane with the
exception of that of the beach sample which lies in the plane of the
beach surface.

All grains were not counted because in some cases it was impos-
sible to determine the true shape of a grain with the stereoscopic view

afforded by the binocular.

Leach m (Figures 3 and 1L)

The beach sample was obtained near the top of the wave limit on
Lake Michigan, east of Gary, Indiana. The strike of the beach at this
location was N 80° 1, the strike of the incoming waves was N 811° F, and
the wind direction was approximately N 25° 1. The sample was oriented
N-S in the plane of the beach which dipped nine degrees to the north.

The diagrams (Figures 3 and h) of the y; and m.p.a. show an in-
teresting relationship between the slope of the beach and the action of
the incoming waves. 0n striking the shore, smaller waves were reoriented
perpendicular to the shoreline while the larger waves struck at an angle
and the water expended its energ in a curving horseshoe-like path.

In Figure 3 the l_d_ diagram shows a definite imbrication or shin...

gle-lilce arrangement of the grains toward the wave direction. This

15
arrangement offers mximum resistance to reorientation and least resist-
ance to the flow of the depositing medium. The imbrication of larger

particles in beach and stream deposits has been discussed by Lance."B

 

l"Lahee, F. 3., Field Geolog, McGraw-Eill Book Company, New York, 19141,

pp- 914-95-

 

There are also four small maxima near the strike of the waves and this
suggests some rolling of the grains parallel to the beach. The two
smaller maxima located at the shoreward edge might be explained as in-
brication toward the returning waves; one toward the weaker waves re-
turning directly and the other toward the stronger waves returning by
a curving path.

The m.p.a. diagram (Figure 15) has little interpretive value
except to support the theory of imbrication and to show that. the macr-
ity of the grains lie with their m.p.a. close to the plane of the beach

slope. The results are very similar to those obtained by Krumbein* in

.Km‘bein. We Ce. Q'Ee 24.5." Ppe 702.705e

 

his work on dolomite pebbles.

Current giggle-n35;

The current ripple-mark was collected near the beach south of
Grand Haven, Michigan. It was chosen because its axis did not lie per-
pendicular to the current direction and the resulting diagram shows
the combined effects of both current and slopes. Close observation dis-
closed that the ripple contained three distinct and different slopes and

petrofabric diagrams were prepared for each of these.

 

 

    

     
 
 
    

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Beach Sample
>3-2-|-0 7° ' m.p.a. Fabric >5‘4‘3'2'O °/o

Beach Sample

Long-dimension Fabric ' . .
Strike of beach X-X', Strike of waves Y~Y‘ Strike of beach X-X, Strike of waves Y-Y

Figure 4.

Figure 3.

 

17

Cross section of current ripple-mark '(ZX)

 

Wave length - 3.2 inches
Amplitude - 0.23 inches

Top 'view - current ripple-mark (2X)

A B C D

 

 

 

 

 

Figure 5. Cross Section and Top View of Current Rippleamark

18

In the area” from A to 3 (Figure 5), which sloped toward the cur-
rent direction, both the m.p.a. and y; diagrams (Figures 6 and 7) showed
a distinct imbrication toward the current direction.

In Figures 8 and 9, representing the area from B to C, the effects
of both current and slope were apparent. There was a noticable girdle
from lower left to upper right which corresponds to the plane and direc-
tion of the slope. The maxima of both the lg and m.p.a. have been
pushed to the left and right respectively because of the effects of the
slope.

The area from C to D (Figures 10 and ll) showed a diminished im-
brication in the current direction and the development of fairly strong
maxima at the sides. These mxima my represent grains rolling perpen-
dicular to the current direction because of the turbulence of the cur-
rent after passing over the crest of the ripple-mark. This possibility

of rolling grains was also supported by the m.p.a. diagram (Figure 10).

mam-ma (151.1 as 1.2.. liken.)

The wind ripple-mark was collected from the same area as the
beach sample east of Gary, Indiana. The l_d diagram of the windward
slope (area from A to 3) showed scattered mime. while the fabric of the
lee slope had a well-developed elongation parallel to the direction of
wind. This coincides with the origin of wind ripple-marks as described

by Gilluly" who says the windward slopes are bombarded by the impacts

 

l"Gilluly, J., Waters, A. C., and Woodford, A. 0., Principles of Geolog,

W. H. Freemand and Compaxw, San Francisco, California, 1951, pp. 368-369.

 

l9

 

 

  

at.
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.0...” o: O 0 .
Ce ‘0. .0 . ' . . .
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Current Ripple—mark
m.p.a. Fabric >7~3.5-2-O 9:,

Area from A toB

Figure 7.

Current Ripple-mark
Long-dimension Fabric > 4-3-2-0 "/0
Area from A to 8

Figure 6.

 

 

 

2O

 

 

 

 

 

 

 

 

 

 

 

 

Current Ripple-mark Current Ripple-mark

Long-dimension Fabric >5-4-3-2-O % _ m.p.a. Fabric >4.5‘3'2'O %
Area from B to C ‘ Area from B to C
Figure 9.

Figure 8.

 

 

 

 

 

 

 

 

 

Current Ripple-mark
m.p.a. Fabric >5-4-3-2-O %
Area from CtoU

Figure 11.

Current Ripple-mark
Long-dimension Fabric >4-3-2-O_%
Area from C toD
Figure 10.

 

22
of moving sand grains while the lee slopes are relatively protected.
This splashing effect would probably cause a loss of orientation similar
to that of Figure 1’4. Both m.p.a. diagrams merely showed that the mJor—

ity of grains lie with their m.p.a. in the plane of the slopes.

Oscillation o_r; liege My; (Figures ll, lg t3. g)

The oscillation ripple-mark was formed experimentally in a
small tank one foot wide and four feet long. Short boards dipping to-
ward the center of the tank were placed at the ends to simlate beaches
and to reduce turbulence. The ripples were formed by the oscillatory
action of the water moving between the ends of the tank. It was pre-
sumed, before attempting the experiment, that the l_d_ might parallel the

strike of the ripple as Ingerson"I thought might be the case in his work

 

* Ingerson, 3., Fabric Criteria for Distinguishing Pseudo Ripple-mks

from Ripple-marks: Geological Society 93; America Bulletin, Vol 51,
1940. PP- 557-570.

 

using the optic axis of quartz. A strong mxinum was found almost
parallel to the ripple-mark axis in both trough and crest areas, but
there was also an equally strong mimum perpendicular to the axis and
parallel to the current. The question as to whether this is normally
the case or merely a quirk of the experiment will have to await further
investigation.

The fact that the maxim parallel to the current direction, in
both the trough and slope areas, were located on the same side of the

diagram suggests the future possibility that wave ripple-marks may

23
reveal the direction of paleogeologic shorelines under petrofabric
analysi s.

in interesting observation was the fact that the crest and slope
areas were composed of larger grains, rather loosely packed, while the
trough area was composed of smaller grains, apparently winnowed from

above, and these formed a tight, pavement-like surface.

 

24

Cross section of wind ripple-mark (2X)

 

C
x '\\\\W

che length - 2.6 inches

 

 

 

Amolltude - O.l3 inches
Figure 12. Wind Rippleamark Cross Section

Cross section of oscillation ripple-mark

 

C

«love length - 2.3 inches

 

~«'r'iolitude - 0.2l inches
Figure 13. Oscillation Rippleemerk Cross Section

 

 

 

 

 

 

 

 

 

 

Wind Ripple-mark . Wind Ripple-mark
Long- dimension Fabric > 4-3-2-O% m.p.a. Fabric > 4-3-2-0 "/0
Area from A to B , Area from A to 8
Figure 14. Figure 15.

A, "“3 _4 _.

 

 

 

 

 

 

 

 

 
  
  

Wind Ripple-mark Wind Ripple-mark
-m,p.a, Fabric >4-3'2-O % . Long dimension Fabric > 4'3'2‘0 ‘7.

Area from B to C Area from B to C

Figure 16. Figure 17.

 

 

 

 

 

 

' u
f o .
.. C . . ‘ ‘u
C
v . '
.
‘ C
d o
t C
Q ‘. ‘ O
Q o
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'.
.‘
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1’
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gy- ' , c = '
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Oscillation Ripple-mark .
Long-dimension Fabric > 4-3-2-0 %
Area from A to 8

Figure 18.

 

 

Oscillation

m.p.a.

 

 

 

 

Fabric
Area

Ripple-mark
>7-4-2-O ‘73
from A toB

Figure 19.

 

 

 

 

 

 

 

 

 

 

‘ Oscillation Ripple-mark
Fabric - >5 ~4-2-O 0/0 Long dimensmn Fabric >4-3-2-O "/0

Area from B to C , Area from B to C
Figure 20. Figure 21.

Oscillation Ripple-mark

m. p. a.

 

 

 

 

 

CONCLUSION

The evidence obtained during the completion of this problem shows
definitely that the physical shapes of individual sand grains cause them
to respond to both depositional agents and environments by the preferred
orientation of certain physical dimensions. The explanations of the
orientation diagrams were necessarily both general and theoretical be—
cause or the lack of published research in the field of sedimentary
petrofabrics. Further work, incorporating such factors as roundness,
size, shape, sphericity, compaction, and their effect upon preferred
orientation must be completed before valid information as to sediment
source direction or the agent of deposition can be inferred from the
petrofabric analysis of elastic sediments. With further research, petro-
fabrics my be applied also to other sedimentary problems such as the
settling of foundations, porosity and permeability.

The use of polar co-ordinate paper was found to be more rapid
and equally as accurate as the ”Schmidt" equal area net.

The three-axis universal stage proved to be very rapid in deter-
mining the position of both the long dimension and maximum projection.
Ordinarily these would have to be measured separately, but by means of
the hemisphere, both can be observed and recorded for a single grain at
the same time.

The use of plastics in obtaining oriented samples of unconsoli-
dated material offers a satisfactory method of obtaining these in per-
manent form. An added advantage of this method is the possibility that
after petrofabric analysis, the plastic can beeasily dissolved and the

sample becomes readily available for other types of sedimentary study.

BIBLIOGRAPHY

Books

Gilluly, J., Waters,.1. 0., and Voodford,.A. 0., Principles g£_Geologz.
San Francisco, California: W. H. Freeman and Company, 1951.

Lahee, F. H., Field Geologz. New York: McGras-Hill Book Company, l9ul.

Articles

Dapples, E. 0., and Rominger, J. F., “Orientation Analysis of Fine—grained
Clastic Sediments," Journal giDGeologz, Vol. 53, 1995, pp. 2u6-261.

Ingerson, 1., ”Fabric Criteria for Distinguishing Pseudo Ripple Marks
from.Ripple Marks,“ Geological Survez gf_America Bulletin, vel. 51,

19“0. PP- 557-57“-

Ingerson, 3., and Ranisch, J. L., "Origin of Shapes of Quartz Sand Grains,"
American Mineralogist, Vol. 27, l9u2, pp. 595-606.

Krumbein, W. 0., IPreferred Orientation of Pebbles in Sedimentary
Deposits," Journal 9;.Geologz, Vol.-M7, 1939, pp.-b73—706.

Rowland, B..L., ”Grain-shape Fabrics of Glastic Quarts,‘ Geological
Survez 9; America Bulletin, Vol. 57, 19%, pp. 5h7-56 .

Schrarsadher, W., ”Grain Orientation in Sands and Sandstones,‘ Journal
9;;Sedimentary Petrologz, Vol. 21, 1951, pp. 162-172.

Smith, H. l., and Moodie, 0. D., ”Gollection and Preservation of Soil
Profiles,‘I Soil Science, vol. 6“, 19u7, pp. 61-67.

 

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