Question 1

Which of the following influences the development of landforms through fluvial erosion?

Accepted Answer

All of these (tectonic activity, lithology, geologic structure, and climate) can influence the development of landforms through fluvial erosion. Tectonic activity can cause uplift and deformation of the land, which can affect the slope and direction of rivers. Lithology refers to the type of rock or sediment that makes up the land, which can vary in resistance to erosion and affect the shape and size of river channels. Geologic structure, such as faulting or folding, can also impact the slope and direction of rivers. Climate affects the amount and intensity of rainfall, which can affect the volume and force of flowing water in a river.

Question 2

An area consisting of mudstones and shales will likely exhibit gentler slopes than those composed of hard metamorphic and igneous rocks.

Accepted Answer

Mudstones and shales are generally softer and less resistant to erosion compared to hard metamorphic and igneous rocks. As a result, areas composed of mudstones and shales are more likely to have gentler slopes due to the less steep angles that can be maintained by the softer rocks.

Question 3

A ____ is where steeply tilted, resistant layers form steep-sided ridges.

Accepted Answer

The term "steep-sided ridge" describes a hogback, which is formed by tilted, resistant layers. A cuesta is also formed by tilted rock layers, but is typically a gentle slope on one side and a steep slope on the other. A dome is a circular uplifted structure with rock layers sloping downward, and a mesa is a flat-topped hill with steep sides. Therefore, D is the best choice.

Question 4

The Appalachian Mountains are dominated by many examples of this topography.

Accepted Answer

The Appalachian Mountains are known for their ridge and valley topography, featuring long, narrow ridges parallel to one another with valleys in between. This is a result of the folding and faulting of rock layers that occurred during the mountain-building process. The other options (hogback, dome, cuesta) may occur in mountainous regions but are not dominant features of the Appalachian Mountains.

Question 5

In which area would stream erosion be a more important factor in rapidly forming landscapes?

Accepted Answer

The Himalayas are a rapidly uplifting mountain range where stream erosion plays a significant role in shaping the landscape due to the steep slopes and high rates of precipitation, which increase the erosive power of streams.

Question 6

Which statement is most true with regards to faults and stream erosion?

Accepted Answer

Fault scarps are typically steep slopes created by a fault line shifting, but they are not necessarily resistant to erosion. However, with time, erosion can change the shape and sharpness of a fault scarp. Thus, Option C is the most accurate statement. Option A is not completely correct because faults can be modified by erosion. Option B is not accurate because it implies that all fault scarps undergo significant erosional change.

Question 7

The potential energy of water is greater in steeper areas than in areas of high relief.

Accepted Answer

The potential energy of water is related to its height above a reference point. In steeper areas, water is higher above the reference point, thus having greater potential energy. In areas of high relief, there may be significant variation in elevation, but if the slope is gentle, the water may not be as high above the reference point and therefore have lower potential energy.

Question 8

Which erosional landform forms from stream erosion of intrusive igneous structures?

Accepted Answer

Granitic domes are landforms that form from the erosion of intrusive igneous structures by streams. Buttes, mesas, and caprocks are typically associated with sedimentary rocks and not intrusive igneous structures.

Question 9

High drainage densities are usually related to:

Accepted Answer

High drainage densities are typically observed in areas with high rates of erosion, meaning that the landscape is actively being shaped and eroded by water flow. This results in a dense network of channels and streams, which in turn promotes further erosion as water is able to quickly move and transport sediment through the system.

Question 10

The Appalachians are characterized by this type of drainage:

Accepted Answer

The Appalachians are characterized by trellis drainage, which is a pattern that develops in folded landscapes, like the valleys and ridges found in the Appalachian Mountains.

Question 11

The type of drainage pattern that form around volcanic cones is:

Accepted Answer

Radial drainage patterns form around volcanic cones, as water drains away from the central peak in all directions.

Question 12

The Black Hills of South Dakota exhibit _____ drainage.

Accepted Answer

The answer of The Black Hills of South Dakota exhibit...

Question 13

In an area where tectonic uplift has formed a ridge and a stream cuts into the ridge as it was developing, the stream is termed:

Accepted Answer

The answer of In an area where tectonic uplift has...

Question 14

Stream capture usually results from headward erosion across a divide separating drainage systems.

Accepted Answer

Stream capture occurs when a stream erodes backwards enough to intersect and divert the flow of another stream that previously flowed in a different direction, typically across a divide separating drainage systems. This results in one stream capturing the drainage of the other stream.

Question 15

When one stream diverts from one channel into another similar to the Upper Kafue River seized by the Loer Kafue River, this is known as:

Accepted Answer

When one stream diverts from one channel into another, it is known as stream capture.

Question 16

According to John Hack, landscapes are in dynamic equilibrium when the slopes of hills and valleys do not change over time.

Accepted Answer

John Hack proposed the concept of dynamic equilibrium in landscapes, suggesting that landscapes can reach a state where, despite ongoing processes of erosion and deposition, the overall shape of hills and valleys remains stable over time. This means that the rates of uplift and erosion are balanced, leading to a landscape that does not change significantly, maintaining its general form and slopes.

Question 17

What is William Morris Davis known for?

Accepted Answer

The cycle of erosion is a model of landscape evolution developed by William Morris Davis. It describes the sequence of stages that a landscape goes through as it is eroded by water, wind, and ice.

Question 18

What can cause stream rejuvenation?

Accepted Answer

Stream rejuvenation is typically caused by tectonic uplift, which raises the elevation of the stream bed and forces the stream to cut down into the landscape in order to maintain its gradient. This can result in the creation of new features like waterfalls and deep canyons, and can also cause changes in the stream's channel morphology and flow characteristics. Subsidence and increases in sediment load or temperature are generally seen as factors that contribute to stream degradation, rather than rejuvenation.

Question 19

In the cycle of erosion, landscapes are worn down to ____.

Accepted Answer

The cycle of erosion involves the gradual wearing down of landscapes through processes such as weathering, erosion, and deposition. Eventually, the land is eroded down to a nearly flat surface known as a peneplain.

Quiz 40: Landscapes Shaped by Stream Erosion