Growth of Present�Day Concepts, 1978-1988
A
'
Fig. 2.37. The fo rmation of a flow�separation zone and silt
banks on a point bar. (Nanson 1980)
KEY TO SYMBOLS
M"d
Sand
lnterlaminated
sand and mud
Inclined strata
Intraformational
conglomerate
Trough cross-beds
Erosional
1
Gradational
S Contact
Fig. 2.38. Nomenclature for the description of inclined
heterolithic stratification (IHS). A Vertically stacked sets,
each individually may be 1-30 m thick; B individual IHS
units, comprising graded couplets 1 em to several meters
in thickness; C imbricate sets; D composite sets; IHS set
51
by Cant and Walker (1976). This model is illustrated
in Fig. 2.20, and was used by Miall (1978c), together
with that of the Platte River, as the two major classes
of sandy-braided river for the purposes of defining
vertical�profile facies models. Cant and Walker
(1978) described the development of "sand flats" by
the process of nucleation of small sand bars, which
then grow by lateral and downstream capture and
turning of migrating transverse and li. nguoid bedforms. However, in their work, they did not consider
the internal architecture of the sand flats, and their
diagrams imply that the structure is tabular. Subsequent architectural work by Miall (1988a,b,c), discussed in detail in Chap. 6, shows that the sand
flats contain significant internal three-dimensional
structure.
N.D. Smith and D.G. Smith (1984) described the
William River, a suspended-load stream showing
steady discharge that becomes characteristically
braided, with linguoid bedforms and sand flats similar to those of the Platte River) where abundant sand
bedload is added by eolian processes.
Bristow (1987) carried_out a reconnaissance of the
Brahmaptura River, one of the world ) s giant braided
rivers. Earlier work on this river by Coleman (1969)
was of considerable significance in establishing
the style of bedform generation in deep) vigorous
showing the three types of IHS geometry; E dip section,
showing three types of geometry of discontinuous lamina¥
tion (1-3); F plan view ofbar showing three possible types
of along-strike continuity (1-3). (Thomas et al. 1987)
A
'
Fig. 2.37. The fo rmation of a flow�separation zone and silt
banks on a point bar. (Nanson 1980)
KEY TO SYMBOLS
M"d
Sand
lnterlaminated
sand and mud
Inclined strata
Intraformational
conglomerate
Trough cross-beds
Erosional
1
Gradational
S Contact
Fig. 2.38. Nomenclature for the description of inclined
heterolithic stratification (IHS). A Vertically stacked sets,
each individually may be 1-30 m thick; B individual IHS
units, comprising graded couplets 1 em to several meters
in thickness; C imbricate sets; D composite sets; IHS set
51
by Cant and Walker (1976). This model is illustrated
in Fig. 2.20, and was used by Miall (1978c), together
with that of the Platte River, as the two major classes
of sandy-braided river for the purposes of defining
vertical�profile facies models. Cant and Walker
(1978) described the development of "sand flats" by
the process of nucleation of small sand bars, which
then grow by lateral and downstream capture and
turning of migrating transverse and li. nguoid bedforms. However, in their work, they did not consider
the internal architecture of the sand flats, and their
diagrams imply that the structure is tabular. Subsequent architectural work by Miall (1988a,b,c), discussed in detail in Chap. 6, shows that the sand
flats contain significant internal three-dimensional
structure.
N.D. Smith and D.G. Smith (1984) described the
William River, a suspended-load stream showing
steady discharge that becomes characteristically
braided, with linguoid bedforms and sand flats similar to those of the Platte River) where abundant sand
bedload is added by eolian processes.
Bristow (1987) carried_out a reconnaissance of the
Brahmaptura River, one of the world ) s giant braided
rivers. Earlier work on this river by Coleman (1969)
was of considerable significance in establishing
the style of bedform generation in deep) vigorous
showing the three types of IHS geometry; E dip section,
showing three types of geometry of discontinuous lamina¥
tion (1-3); F plan view ofbar showing three possible types
of along-strike continuity (1-3). (Thomas et al. 1987)