Flooding

Question 1

1. A stream may overflow its banks when the its ability to carry water is overwhelmed by the sheer volume of water flowing off the landscape and create what is known as a?

Answer 1

Flood

Question 2

5. Provides information about a river or stream by simply plotting the discharge versus time.

Answer 2

Stream hydrographs

Question 2

2. Its a process where water flows through stream channels

Answer 2

Run off

Question 2

6. This is the amount of time for water to move across the landscape and into channels

Answer 2

Lag time

Question 2

4. This is the discharge of groundwater into the surface environment

Answer 2

Groundwater Baseflow

Question 2

3. Precipitation reaching the land surface moves downslope in thin sheets

Answer 2

Overland flow

Question 3

11. This term is often applied to the larger stream that serves as the principal channel within a drainage system.

Answer 3

River

Question 3

7. Continuous input of groundwater baseflow allows streams in many areas to keep flowing at some minimum level, often called ________.

Answer 3

Baseflow Condition

Question 3

8. These are a result of less deep infiltration in arid areas resulting in a water table that is below the level of most stream channels.

Answer 3

Losing Streams

Question 3

10. High precipitation allows more water to infiltrate to the water table which causes the water table in humid regions to be higher than the streams channel, thereby forcing groundwater to flow into streams. Such streams are often referred as ?

Answer 3

Gaining Streams

Question 4

9. In a losing stream, where do water flows into?

Answer 4

Groundwater system

Question 5

12. It is a network of stream channels where merging tributaries (smaller of any two merging channels) form progressively larger streams.

Answer 5

Drainage system

Question 6

14. Individual systems are separated from one another by a topographic high or crest in the landscape called a?

Answer 6

Drainage divide

Question 7

13. The upper portion of the drainage system is called the __________ , whereas the ____________ is found in the lower part of the system where a river empties into an ocean, lake, or another river.

Answer 7

headwaters;
mouth

Question 8

15. Based on discharge, what is the largest river in the world?

Answer 8

Amazon River

Question 9

16. What is the 2nd largest water basin in the Philippines? what is its total land area?

Answer 9

Mindanao River Basin;
21, 503 km2

Question 10

17. These are any smaller streams that feed larger streams within a drainage basin.

Answer 10

Tributaries

Question 11

18. A method of classifying or ordering the hierarchy of natural channels.

Answer 11

Strahler Stream Order

Question 12

19. ____________ correlates well with drainage area, but is also regionally controlled by topography & geology.

Answer 12

Stream Order

Question 13

20. Reflects downstream trade off between discharge and slope in setting transport capacity (and thus ability to move sediment and incise rock).

Answer 13

Longitudinal Stream Profile

Question 14

21. The level below which a river or stream cannot incise.

Answer 14

Base level

Question 15

22. What is the formula for Drainage density?

Answer 15

Total stream channel length (l) OVER the area of the drainage system(A)

Question 16

23. Steep terrain tends to be highly
    dissected and thus have ______________________.

Answer 16

high drainage density

Question 17

24. High drainage density but
    small source areas. Location: ____________________

Answer 17

Mancos Shale Badlands, Utah

Question 18

25. High drainage density, small source areas in the PH. Location:

Answer 18

Rill field, Mt. Pinatubo, Philippines

Question 19

26. types of DRAINAGE PATTERNS

Answer 19

Dendritic;
Parallel;
Trellis;
Rectangular;
Radial;
Annular;
Multibasinal;
Contorted;

Question 20

27. Most commonly formed on horizontally bedded and uniform sediments or on uniformly resistant crystalline rocks.

Answer 20

Dendritic

Question 21

28. Usually develops on moderate to steep slopes, but also where regional structure, such as outcropping resistant rock bands, are elongated and parallel.

Answer 21

Parallel

Question 22

29. Patterns most commonly on dipping or folded sedimentary or weakly metamorphosed sedimentary rocks; also areas of joints and faults which intersect with right angles and old sand dunes with parallel alignment

Answer 22

Trellis

Question 23

30. Usually have a more or less perpendicular turns mainly caused by criss-crossing fractures.

Answer 23

Rectangular

Question 24

31. Occurs around domes or cones, and particularly common on volcanic areas

Answer 24

Radial

Question 25

32. Patterns also develop around domes, where there exists alternating resistant and weak beds, so that the major channels cut through the strike and the low order streams follow the dip of the rocks.

Answer 25

Annular

Question 26

33. Are loose rock particles/sediments deposited on a stream.

Answer 26

Alluvium

Question 27

34. One of the key factors in a stream’s ability to erode the landscape is the?

Answer 27

Velocity of the water

Question 28

35. Are unstable overhang located at the outer bank which is produced by the velocity increase on the outer bank which subsequently enhances the ability of the water to cut (erode) into the bank.

Answer 28

Cutbanks

Question 29

36. On the inner bank where velocity decreases, sediment tends to accumulate and form a deposit known as a ____________.

Answer 29

Point bar

Question 30

37. Downcutting by streams is not performed by the water
    itself, but rather by the sediment that physically scrapes
    or wears away rock in a process called _____________.

Answer 30

Abrasion

Question 31

38. Sea level is often referred to as the?

Answer 31

Ultimate base level

Question 32

39. The process whereby water separates sediment grains based
    on their size, shape, and density is called?

Answer 32

Hydraulic Sorting

Question 33

40. Describes the fraction of solid particles that is in a suspended state and moving at the same velocity as the water— suspended material is what makes streams appear muddy.

Answer 33

Suspended Load

Question 34

41. Consists of sediment particles that roll, bounce, or remain stationary on the streambed.

Answer 34

Bedload

Question 35

42. These are mound-shaped channel deposits consisting of sorted material ranging in size from boulders to coarse gravel to fine sand.

Answer 35

Bar

Question 36

43. Are large fan-shaped deposits that form where steep mountain streams empty out onto valley floors at the mouth of rivers.

Answer 36

Alluvial fan

Question 37

44. Streams also transport considerable amounts of dissolved ions (charged atoms) in what scientists refer to as the

Answer 37

Dissolved Load

Question 38

45. Are formed when a river enters a lake or ocean and splits into smaller channels and begins to deposit sediment due to a decrease in velocity.

Answer 38

Delta

Question 39

46. Based on the maximum yearly discharge, a _______________ can be calculated for each value, which represents the frequency a particular discharge value can be expected to repeat itself.

Answer 39

recurrence interval

Question 40

47. The ability of the ground to absorb water, referred to as ______________, plays a critical role in flooding because water that is unable to infiltrate is generally forced to move as overland flow.

Answer 40

infiltration capacity

Question 41

48. Because small channels are more abundant in the upper parts of a basin, flash floods are also referred to as ________________.

Answer 41

upstream floods

Question 42

49.

Question 43

50.

Question 44

51.

Question 45

52.

Question 46

53.

Question 47

54.

Question 48

55.