Geology 112 Exam 2 Questions 3 – Flashcards

The flat-lying area surrounding a river channel is termed the____.

The lowest elevation to which a stream can downcut is the___.

The deepest part of the channel, where the stream flows fastest, is the___.

The slope of a streambed measured at some point along its course is the___.

In uniform sediments with a relatively constant slope at the surface, a _____ drainage network is expected.

In a region with prominent orthogonal sets of joints, a ____ drainage network is expected.

In a region characterized by a parallel series of ridges and valleys, a ____ drainage network is expected.

In the region immediately surrounding an isolated volcano, a _____ drainage network is expected.

True or false. All flowing, as opposed to standing, water on the Earth's surface is confined to stream channels.

True or false. If a stream cuts through flat-lying sediments to reach an anticline produced in an ancient orogenic event, the course of the stream will likely be unaffected.

V-shaped stream valleys result from the downcutting of stream erosion and _____.

Ephemeral streams do what?

Meandering streams____.

Pirate streams___.

Braided streams____.

Which stream has greater competence? -a small mountain stream -the Mississippi River

Which has greater capacity? -a small mountain stream -the Mississippi River

True or false. The average velocity of a stream is always greatest near its source.

All else being equal, a deep, narrow stream will flow _____ a shallow, broad stream.

Moving away from its headwaters, the flow of the stream becomes more______.

True or false. The sediment load of a stream consists of only those grains that are fine enough to stay in suspension.

The stream gradient of most rivers___.

As the velocity of flow decreases, _____.

Ultimately, the base level of a stream valley can be no lower than_____.

The base level of a stream rises when it encounters a lake because____.

The distinction between a valley and a canyon is____.

At a waterfall, where two sedimentary lithologies are juxtaposed, which lithology is more likely to form the cliff over which the water falls?

Within a meander, where is the sediment most likely to be deposited?

The inner edge of a meander, where sediment is deposited, is a___.

The outer edge of a meander, where material is being eroded is a___.

A meander that is cut off to become completely isolated from the main channel, and which dries up, is an____.

A meander that is cut off to become completely isolated from the main channel, but retains water is an____.

A thin strip of land separating abutted cut banks on opposite ends of a meander is a____.

True or false. The deltas of all major rivers consist of multiple radiating lobes of sediment in a "bird's foot" configuration, similar to the Mississippi River delta.

The discharge of a river traveling through a humid region will typically ____ downstream; the discharge of a river traveling through an arid region will typically ___ downstream.

True or false. All flooding events occur so rapidly that there is no time to alert people in harm's way.

True or false. A 100 year flood is more destructive catastrophic than a 50 year flood.

If a 50 year flood occurs on the Mississippi River in 2010, what is the probability that a flood of at the same magnitude will occur in 2011?

True or false. All the water in rivers and streams arrives directly from rainfall runoff.

Which river is a threat to capture the flow of the Mississippi River through stream piracy?

The primary stream fed by tributaries within a drainage basin is termed a____.

All else being equal, water will flow faster in a stream that has a ____.

All else being equal, water will flow faster in a stream with___.

At a delta, ____.

The shape of the delta is primarily determined by____.

True or false. Although the Nile River is longer, the Amazon River has the greatest discharge of any stream on Earth.

True or false. Geological evidence suggests that many millions of years ago, the Amazon flowed toward the west rather than the east.