lab 8
Stream terrace
Step-like landform found above a stream and its flood plain.
Oxbow lake
a U-shaped body of water that forms when a wide meander from the main stem of a river is cut off, creating a free-standing body of water
radial drainage
a drainage pattern in which consequent streams radiate or diverge outward, like the spokes of a wheel, from a high central area; it is best developed on the slopes of a young, unbreached domal structure or of a volcanic cone.
annular drainage
a drainage pattern in which streams follow a roughly circular or concentric path along a belt of weak rock, resembling in plan a ringlike pattern.
rectangular drainage
a drainage pattern in which the main streams and their tributaries display many right-angle bends and exhibit sections of approx. the same length
Alluvial fan
a fan-shaped mass of alluvium deposited as the flow of a river decreases in velocity
Meander scar
a geological feature formed by the remnants of a meandering water channel
Stream piracy
a geomorphological phenomenon occurring when a stream or river drainage system or watershed is diverted from its own bed, and flows instead down the bed of a neighboring stream.
Competence (of a stream)
a measure of the maximum size of the particles that the stream can transport
Peneplain
a more or less level land surface produced by erosion over a long period, undisturbed by crustal movement
braided stream
a stream consisting of multiple small, shallow channels that divide and recombine numerous times forming a pattern resembling the strands of a braid.
meandering stream
a stream following a sinuous flow consisting of successive meanders.
Antecedent (or superimposed) stream
a stream that maintains its original course and pattern despite the changes in underlying rock topography.
geologic map
a two-dimensional map representing the rock formations exposed at Earth's surface
What type of feature is illustrated in the figure below?
alluvial fan
Point bar
an alluvial deposit that forms by accretion on the inner side of an expanding loop of a river
Floodplain
an area of low-lying ground adjacent to a river, formed mainly of river sediments and subject to flooding
Drainage divide
an elevated boundary that separates neighboring drainage basins
Study the Sundance, Wyoming (around Green Mountain) map and determine the drainage pattern.
annular drainage pattern
Study the Madison River on the Ennis, Montana map and determine whether the stream type is braided or meandering.
braided stream
What type of stream is illustrated in the figure below?
braided stream
old age stage erosion
broad, open valleys with widely meandering streams, indistinct divides, erosion remnants of resistance lithologies, surface near erosional base level.
What type drainage pattern is illustrated in the figure below?
dendritic
Classify the drainage pattern for Plate 41 (Red Wash, New Mexico; on the plateau).
dendritic drainage pattern
Study the Crowder, Mississippi map and determine the drainage pattern.
dendritic drainage pattern
Give the stage of regional erosion for the Kaaterskill, New York
mature
Study the Plate 40 (Bear Creek, South Dakota) and determine the stream type is braided or meandering.
meandering stream
Study the Tallahatchie River on the Crowder, Mississippi map and determine the stream type is braided or meandering
meandering stream
what type of stream is illustrated in the figure below
meandering stream
dendritic drainage
occurs when the tributary systems subdivide headway like the limbs of a tree.
trellis drainage
occurs where subparallel streams erode a valley along the strike of less resistant formations.
Give the stage of regional erosion for the Crowder, Mississippi
old age
What type of feature is Horseshoe Lake in the figure below from the Crowder, Mississippi map?
oxbow lake
What type drainage pattern is illustrated in the figure below?
radial
Drainage basin
the area drained by a river and all its tributaries
Gradient (or slope)
the grade measured by the ratio of drop in elevation of a stream per unit horizontal distance
Base level
the lowest point to which it can flow, often referred to as the 'mouth of the river'
Cut bank
the outside bank of a water channel (stream), which is continually undergoing erosion
Capacity (of a stream)
the total amount of sediment a stream is able to transport
mature stage erosion
well-drained terrain, all in slopes except floodplains; some tributaries streams meander; maximum relief.
Give the stage of regional erosion for the figure below?
youthful
youthful stage erosion
V-shaped valleys with few or no floodplains; many falls and rapids plus some lakes and swamps.