Lab 7 Assignment_Online
docx
keyboard_arrow_up
School
Georgia State University *
*We aren’t endorsed by this school
Course
1113L
Subject
Geography
Date
Feb 20, 2024
Type
docx
Pages
9
Uploaded by JusticeNewt2561
Lab 7: River Systems
GEOG 1113L – Introduction to Landforms Lab
Name: __Anora Oromoni___________
I.
How Rivers Shape the Landscape
1.
What are the two defining factors that distinguish how water moves in a stream? Erosional forces and Gravity.
2.
What are the different sources of water in a stream system? Tributaries and Channel. Water enter into the system through Precipitation, Snowmelt, and underground springs. 3.
What are the different names for the entire area that encompasses the main channel and all of its tributaries, all of which drain to a single point? Stream system, drainage basin, or watershed. 4.
Describe what first order streams are. First order streams are streams with no tributaries. Often the headwaters which are spring-fed streams at a higher elevation than the rest of the drainage basin. A first order stream may be very small, seasonal or ephemeral and not have a formal name.
5.
What is stream gradient and what is its primary influence? A stream gradient is the elevation the
stream drops over a given distance. It influences the stream energy, or how much work the stream can do. 6.
__Stream load_______ describes how much sediment a stream can carry and dissolve.
7.
As the stream gradient and velocity of the river changes, stream load changes as well. High velocity carries a _suspended ____ load (fine particles), while low velocity carries a __bed___ load (larger particles). 8.
What is the difference in location between an alluvial fan and a delta? An alluvial fan often appears at the base of a mountain. A delta can be at the mouth or end of the zambezi river as it flows out into the Indian ocean. 9.
Describe a river with high sinuosity. Sinuosity is the meanders, or the bends in a river. A river with high sinuosity is a river that has a very meandering course. This means that the river bends and turns frequently, forming a series of loops and curves. 10.
In a meandering river, the _inner__side of the river is slower and deposits sediment, while the _outer__side of the river is faster and deeper.
II.
Sediment Load
Fill in the diagram below using the definitions and terms provided. Saltation
Traction
Stream Bed
Rolling Grain
Suspended Load
Bed Load
Solution (Dissolved) Load
Stream Current
III.
Drainage Patterns
Visit the link below and use it to help you answer the following questions. Link: https://www.geologyin.com/2014/03/drainage-pattern.html
1.
What type of drainage pattern is shown in the image above? Centripetal Drainage Pattern
2.
What type of fold landform did you recently learn about that would have this drainage pattern? Centripetal drainage patterns commonly develops on basins
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
3.
What type of drainage pattern is shown above? Parallel drainage pattern. 4.
What kind of topography typically hosts this drainage pattern? Parallel drainage patterns are typically found in areas with steep slopes and uniform topography. Because of the steep slopes, the streams are swift and straight, with very few tributaries, and all flow in the same direction. 5.
What type of drainage pattern is shown above? Trellis drainage pattern. 6.
Describe two environmental implications for this drainage pattern. They can increase the risk of flooding, as the streams are more likely to overflow their banks during heavy rains. They can also
make it difficult to develop land, as the streams can create barriers to transportation and development.
7.
What type of drainage pattern is shown above? Radial drainage pattern
8.
On what landforms do you typically see this pattern? Isolated volcanic cones or domes.
9.
What drainage pattern is shown above? Dendritic drainage pattern
10.
Describe the setting for this drainage pattern to form. T
hese develop in areas where the rock such as granite, gneiss, volcanic rock, and sedimentary rock which has not been folded (or unconsolidated material) beneath the stream has no particular fabric or structure and can be eroded equally easily in all directions.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
11.
What drainage pattern is shown above? Rectangular drainage pattern
12.
What is the primary cause for this pattern? It develops in the area that have very little topography and a system of bedding planes, fractures, or faults that form a rectangular network.
13.
What pattern occurs when there has been significant geological disruption? Deranged drainage pattern
14.
Which pattern contains tributaries that point in the opposite direction of the main stream’s flow? Barbed drainage pattern
15.
Which drainage pattern do you find most interesting and why? I find the barbed drainage pattern
to be the most interesting. It is a unique drainage pattern that is formed by the capture of a main stream by another stream. This can happen when there is a change in the landscape, such as a tectonic event or a landslide.
16.
IV.
Stream Discharge
Follow steps A – H below, then answer the following 4 questions. A.
Navigate to the USGS Water Dashboard, at
https://dashboard.waterdata.usgs.gov/
B.
Notice the colored dots, depicting real-time conditions at stream gages nationwide. The dots are colored to show you if the streamflow is unusually high or low for this day of the year. Red colors
are unusually low; blue colors are unusually high. You can click on “legend” at the upper right to see what the colors mean. For example, the dark blue color indicates that the flow is at or above
the 90
th
percentile, which tells you that at least 90% of the flows measured on this day in the past were lower. Put another way, flow is high enough to earn the dark blue dot only about 10% of the time.
C.
You can click on any of the colored dots to bring up a pop-up window with a plot of discharge over the past week. Try this now, then close the pop-up window when you are finished.
D.
Under the “Layers” tab, click on the “Water Quality” drop-down menu. Select the drop-down menu that says “All” and select "Water Temperature”. Then select the “OFF” switch below so it is
green and says “ON”.
E.
Let’s look at a specific stream gaging station, on the Neversink River in New York. In the search box at the upper left, type “neversink,” then select the Neversink Reservoir in Sullivan County, New York. This reservoir is one of several that supply New York City with drinking water. You can
scroll to zoom into the map and see the reservoir. Note the gaging stations on the inflow and outflow of the reservoir. Click on the dot upstream (north) of the reservoir – you want the one called “Neversink River near Claryville, NY (Monitoring location USGS 01435000).” There are several similarly named gaging stations, so be sure you have the correct one. Click on the dot to open the popup window.
F.
Notice that there is a lot of data available for this gaging station. That is because this station was
formerly part of a smaller network of intensively monitored stations in relatively undisturbed locations. These monitoring sites are collectively called the Hydrologic Benchmark Network. (A “benchmark” is something against which other things are measured. In this case, an undisturbed stream is a benchmark against which we can measure a stream modified by human activity.) G.
At the top of the pop-up window, click the link to open the Site Page, which is a more detailed description of the site. Take a look at the data available here: o
Notice that there is a camera view showing the river over the past few days, and even an
infrared camera showing the relative temperature of the water and land.
o
The map shows the drainage basin for this gaging station, which means the area “upstream” where water that originally falls as rain or snow will eventually flow past the gaging station.
o
At the bottom, open the Location Metadata. You can see that the water draining past this point has been collected from a drainage area of 66 square miles.
H.
Scroll back to the top to see the different types of data that we can show. Leaving the range at 7 days, select “Discharge, cubic feet per second” to see a plot showing how discharge has changed over the past week.
Questions
:
1.
Look at the discharge data. How variable was discharge over the past week? You can answer this
in several ways. First, what was the range (the maximum minus the minimum) of the data? Another good way to think about variability is to think about percent change. First, estimate the mean value of the data by looking at the plot. Approximately how much higher (as a percent) are
the highest discharges? Range 114 – 108 = 6. 6 * 100 = 60%. The highest discharge is approximately 60%.
2.
Where you clicked the box to select discharge data, check the box that says, “Select data to graph on second y axis,” and choose “Temperature, water, degrees Fahrenheit (calculated)”. Look at the temperature graph. Based on this graph, what probably drives temperature changes in the Neversink River? Do you think there is any relationship between temperature and discharge? If so, what do you think it might be? Based on the temperature graph for the Neversink River, it is likely that air temperature
and solar radiation
are the primary drivers of temperature changes. There is a relationship between temperature and discharge
in the Neversink River. When the discharge is high, the water temperature is more uniform. When the discharge is low, the water temperature is more variable.
3.
When discharge is high enough, flooding occurs. Is the discharge you observe here unusually high? Unusually low? Typical for the region? Can we answer these questions with only a week’s worth of data? I
t is not possible to say definitively whether the discharge is unusually high or unusually low based on only a week's worth of data. To make this assessment, it would be necessary to compare the current discharge to historical discharge data for the same time of year. This would allow us to see if the current discharge is outside of the normal range of variability.
4.
We might expect flow in a stream to change seasonally. After all, most (or all) of the streamflow that you observe originated as rain and snow falling in the watershed, and precipitation in most places is seasonally variable. Still looking at both discharge and temperature data, go back to the
top and change the time range to 1 Year. It may take a minute to load all the data. Temperature is high in summer and low in winter, as you might expect – but what month was the warmest? The coldest? What months had the highest discharge and the lowest? The months with the highest discharge in the Neversink River are March and April. The months with the lowest discharge are September and October.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help