Growth of Present-Day Concepts, up to 1977
the result of bed defects produced by the turbulent
burst-sweep cycle (see review by Leeder 1983).
A useful review of cross-bedding structures was
provided byTwenhofel (1932; parts of this section of
Twenhofel's book were contributed by Kindle and
Bucher). A description of the development of sandbars (probably what are now termed 2-D and 3-D
dunes) was provided:
"Sandbars move over bottoms of water as plateau"like
areas with steep slopes on the advancing sides. They may
range in height from less than an inch to 10 or more feet,
most of them being a foot or less. The sand is rolled over
the top, which usually undergoes some erosion. Reaching
the edge of the plateau, the sands roll down the slope at the
fr ont. The direction of the fr ont slope is usually not con"
stant and the inclinations have a similar range in direction
... Each bed thus fo rmed has its cross"lamination in one
direction, which may or may not be the same as that of the
beds below and above."
Apart from Sorby's work, the first systematic
mapping of cross-bedding orientation in fluvial deposits appears to have been that of Rubey and Bass
(1925). According to Pettijohn (1962), "Brinkman
(1933) was, perhaps, the first of the 'modern' workers to have a clear concept of the objectives of
paleocurrent research and to develop methods to
fulfill these aims."
" ... through measured observations and statistical analysis
a simple facies characteristic - cross"bedding - might
allow a number of basic, reliable paleogeographic conclusions to be drawn."
Important advances in the statistical treatment of
paleocurrent measurements were made by Reiche
(1938), including the use of stereonets for plotting
poles to cross�bed foresets, and vector methods for
data reduction. McKee (1938, 1939) described the
sedimentary structures of the Colorado River in the
Grand Canyon, and proposed a classification of
ripple cross-lamination; Knight (1929) described
festoon cross-bedding.
Except for the German work, led by Brinkman
(1933), the pace of research in this area was slow,
especially compared to the explosion of paleocurrent studies which took place in the 1950s. Before
this time, the attention of most sedimentologists was
held by petrographic studies, as revealed by the focus
of the first edition of Pettijohn's (1949) textbook,
and by the title of the first professional sedimentological journal, the Journal of Sedimen tary Petrology, founded in 1931. As Pettijohn (1962) has
pointed out, there was much misunderstanding as to
the origins of many sedimentary structures which, in
21
the case of cross-bedding, was not fully resolved
until the various structures were reproduced in exhaustive flume experiments, beginning in the 1950s.
The work of Fisk (1944, 1947) stimulated a renewed
interest in alluvial sedimentation after World War II,
particularly amongst oil companies, who increas�
ingly realized the value of studies of modern environments, and the importance of statistics in
geological applications also gained general recognition. These developments all came together in the
early 1950s to start the surge in knowledge of fluvial
processes that has occurred since the first fluVial
facies model was published by Bernard et al. in 1962
(see Sect. 2.3.6).
A contribution by McKee and Weir (1953) focused attention on the internal arrangement and
contact relationships of hydrodynamic sedimentary
structures, and provided a structure classification
that became widely used. Their recognition of the
importance Of bounding surfaces between cross.: bed
sets was an important step forward that has been
built upon in modern architectural classifications of
fluvial deposits (see Sect. 2.4.3.1, Chap. 4). Statistical
techniques began to be applied to paleocurrent measurements on a systematic basis, including the use of
perfected vector. methods of calculating mean and
dispersion (Curray 1956), moving average methods
for clarifying regional trends (Potter 1955; Pelletier
1958), and the use of analysis-of�variance methods
to unravel the sources of dispersion in samples of
different outcrop scale (Olson and Potter 1954). Tanner (1955) discussed, with a variety of examples
based on his own fieldwork, the use of paleocurrents
in basin analys�s. A much expanded classification of
hydrodynamic sedimentary structures was pro�
posed by Allen (1963a), and this remains the most
comprehensive treatment of the subject, although
other classifications have been proposed since, espe�
dally by workers focusing on specific depositional
environments. The use of paleocurrent measurements in basin analysis and regional paleogeo�
graphic reconstructions was demonstrated in an
innovative case study by Pryor (1960) and reviewed
in two important state�of-the-art publications by
Pettijohn (1962) and Potter and Pettijohn (1963; revised edition, 1977}, and the latter authors produced
an illustrated manual of sedimentary structures for
use in fieldwork, a year later (Pettijohn and Potter
1964). Another useful book on this topic was published by Conybeare and Cro.ok (1968).
A renewed interest in flume work produced some
results of fundamental importance in the early
the result of bed defects produced by the turbulent
burst-sweep cycle (see review by Leeder 1983).
A useful review of cross-bedding structures was
provided byTwenhofel (1932; parts of this section of
Twenhofel's book were contributed by Kindle and
Bucher). A description of the development of sandbars (probably what are now termed 2-D and 3-D
dunes) was provided:
"Sandbars move over bottoms of water as plateau"like
areas with steep slopes on the advancing sides. They may
range in height from less than an inch to 10 or more feet,
most of them being a foot or less. The sand is rolled over
the top, which usually undergoes some erosion. Reaching
the edge of the plateau, the sands roll down the slope at the
fr ont. The direction of the fr ont slope is usually not con"
stant and the inclinations have a similar range in direction
... Each bed thus fo rmed has its cross"lamination in one
direction, which may or may not be the same as that of the
beds below and above."
Apart from Sorby's work, the first systematic
mapping of cross-bedding orientation in fluvial deposits appears to have been that of Rubey and Bass
(1925). According to Pettijohn (1962), "Brinkman
(1933) was, perhaps, the first of the 'modern' workers to have a clear concept of the objectives of
paleocurrent research and to develop methods to
fulfill these aims."
" ... through measured observations and statistical analysis
a simple facies characteristic - cross"bedding - might
allow a number of basic, reliable paleogeographic conclusions to be drawn."
Important advances in the statistical treatment of
paleocurrent measurements were made by Reiche
(1938), including the use of stereonets for plotting
poles to cross�bed foresets, and vector methods for
data reduction. McKee (1938, 1939) described the
sedimentary structures of the Colorado River in the
Grand Canyon, and proposed a classification of
ripple cross-lamination; Knight (1929) described
festoon cross-bedding.
Except for the German work, led by Brinkman
(1933), the pace of research in this area was slow,
especially compared to the explosion of paleocurrent studies which took place in the 1950s. Before
this time, the attention of most sedimentologists was
held by petrographic studies, as revealed by the focus
of the first edition of Pettijohn's (1949) textbook,
and by the title of the first professional sedimentological journal, the Journal of Sedimen tary Petrology, founded in 1931. As Pettijohn (1962) has
pointed out, there was much misunderstanding as to
the origins of many sedimentary structures which, in
21
the case of cross-bedding, was not fully resolved
until the various structures were reproduced in exhaustive flume experiments, beginning in the 1950s.
The work of Fisk (1944, 1947) stimulated a renewed
interest in alluvial sedimentation after World War II,
particularly amongst oil companies, who increas�
ingly realized the value of studies of modern environments, and the importance of statistics in
geological applications also gained general recognition. These developments all came together in the
early 1950s to start the surge in knowledge of fluvial
processes that has occurred since the first fluVial
facies model was published by Bernard et al. in 1962
(see Sect. 2.3.6).
A contribution by McKee and Weir (1953) focused attention on the internal arrangement and
contact relationships of hydrodynamic sedimentary
structures, and provided a structure classification
that became widely used. Their recognition of the
importance Of bounding surfaces between cross.: bed
sets was an important step forward that has been
built upon in modern architectural classifications of
fluvial deposits (see Sect. 2.4.3.1, Chap. 4). Statistical
techniques began to be applied to paleocurrent measurements on a systematic basis, including the use of
perfected vector. methods of calculating mean and
dispersion (Curray 1956), moving average methods
for clarifying regional trends (Potter 1955; Pelletier
1958), and the use of analysis-of�variance methods
to unravel the sources of dispersion in samples of
different outcrop scale (Olson and Potter 1954). Tanner (1955) discussed, with a variety of examples
based on his own fieldwork, the use of paleocurrents
in basin analys�s. A much expanded classification of
hydrodynamic sedimentary structures was pro�
posed by Allen (1963a), and this remains the most
comprehensive treatment of the subject, although
other classifications have been proposed since, espe�
dally by workers focusing on specific depositional
environments. The use of paleocurrent measurements in basin analysis and regional paleogeo�
graphic reconstructions was demonstrated in an
innovative case study by Pryor (1960) and reviewed
in two important state�of-the-art publications by
Pettijohn (1962) and Potter and Pettijohn (1963; revised edition, 1977}, and the latter authors produced
an illustrated manual of sedimentary structures for
use in fieldwork, a year later (Pettijohn and Potter
1964). Another useful book on this topic was published by Conybeare and Cro.ok (1968).
A renewed interest in flume work produced some
results of fundamental importance in the early