EAR 105 Chapter 10 Questions PDF

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chapter 10 quiz review with answers...

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1 Chapter 10

1. The gravel bed load of a stream moves by _____. sliding and rolling 2. _______ are low ridges of flood-deposited sediment that form on both sides of a stream channel and thin away from the channel. Natural levees 3. The movement and interchange of water between the sea, air and land can be visualized by the ____. hydrologic cycle 4. A(n) ___ stream flows in a network of rivulets (subchannels) around numerous sandbars. Braided 5. A stream can increase its length by _____. All of the answers are correct. 6. A ridge or strip of ground separating one drainage basin from another is termed a ____. A Divide 7. Certain features on the planet Mars resemble _____ on Earth. river channels 8. A(n) __ is the body of sediment deposited at the mouth of a river when the river's velocity decreases Delta 9. A "100-year flood" has a _______ percent chance of occurring in any given year. 1 10. Rivers may develop pronounced sinuous (wiggly) curves called a ___ pattern. Meandering 11. A cutoff meander may become a crescent-shaped __. oxbow lake 12. A _____ is a ridge of sediment built by sedimentation on the middle or banks of a stream channel. Bar

13. The ______ is the total area drained by a river and its tributaries. drainage basin

2 Chapter 10

14. A stream's discharge is __. the volume of water passing through a specific point along the stream in a unit of time. 15. Movement of cobbles and boulders by rolling, sliding, or dragging in a streambed is called ____ load. Traction 16. The limit to downcutting of a stream is called the ___ level. Base 17. A ____ drainage pattern is one in which streams diverge outward likes spokes on a wheel. Radial

18. In North America, the ___ separates streams that flow into the Pacific Ocean from those that flow into the Atlantic Ocean and Gulf of Mexico. Continental Divide 19. _____ are low ridges of flood deposited sediment that form on either side of a stream channel and thin away from the channel. Natural levees 20. ___ influences the velocity of a river along with gradient. Channel shape and roughness 21. A river's velocity is faster ____. along the outside of a meander loop near the cut bank 22. A stream can lengthen itself by ____. Headward erosion and deposition of a delta are both correct, but meander-loop cut-off and stream discharge are incorrect. 23. The ______ load is sediment light enough to remain lifted indefinitely above the bottom by water turbulence. Suspension 24. The delta of the ______ River is a wave-dominated delta that resembles the Greek letter delta and is the origin of the name. Nile 25. _____ refers to sand grain movement in a series of short leaps or bounces off the bottom. Saltation

3 Chapter 10

26. _____ meanders are meanders that retain their sinuous pattern as they cut vertically downward below the level at which they originally formed. Incised 27. A graded stream can be deepening its channel by down cutting while part of its energy is also widening its valley by ______ erosion. Lateral 28. A(n) ___ is a step-like landform found above a stream and its floodplain. It is a remnant of an older flood plain or river-eroded flat surface. stream terrace 29. A(n) ____ stream is one that exhibits a delicate balance between its transporting capacity and the sediment load available to it. Graded 30. Flood control structures along the Mississippi River surrounding New Orleans are predominantly _____. artificial levees 31. The process of deepening of a valley by erosion of a streambed is called __. down cutting 32. A(n) ___ drainage pattern of a river resembles a tree. Dendritic 33. ___ is/are sudden localized floods of large volume and short duration, often triggered by heavy rainstorms. Flash floods 34. _______ deposits are found in streams where running water has mechanically concentrated heavy sediment such as gold. Placer 35. Streams erode rock and sediment by ___. All answers are correct.

36. On large alluvial fans, the _____ sediment is deposited near the mountains. coarsest

4 Chapter 10

37. Floods are described by ____, the average time between floods of a given size. recurrence interval

38. Deltas may be river dominated, tide dominated or _____. wave dominated 39. ___ beds form the main body of a delta with angles of inclination up to 20 to 35 degrees in small sandy deltas. Foreset 40. Discharge is the product of average stream width times average stream depth times ___. stream velocity...