study guide
Running Water
• Most important geologic agent in eroding, transporting and depositing sediments
• Nearly every landscape shows erosion or deposition
• Stream- a body of running water confined to a channel that runs downhill under the influence of gravity
1. Headwater- Upper part of stream near its source in the mountains
2. Mouth- A place where a stream enters sea, lake or larger stream
3. Channel- A long narrow depression eroded by a stream into rock or sediment
• Streambeds- bottom of the channel
• Stream banks- sides of the channel
4. Floodplains- flat valley floor composed of sediments deposited by the stream
5. Watershed- higher ridge of land, the boundary between one drainage basin and another
6. Source- The place where a river begins- river system has numerous sources
7. Confluence- A place where two rivers meet
Overground
• Channel flow- Raindrops might fall directly into a river or stream
• Surface Runoff- Water runs downhill over the ground towards a river or stream
1. Rain travelling as surface runoff will get to rivers and streams much more quickly, reaching a river or stream with little delay within a short time-span
2. More likely to flood with surface runoff
3. Surface runoff-> shorter lag time-> higher river peak discharge->more likelihood of flooding
Underground
• Raindrops infiltrates solid and rock. The water then moves underground towards a stream or river.
1. Water that infiltrates and travels underground travels much more slowly, finally reaching a river or stream bit by bit over a much longer period of time
Conditions that will make surface runoff more likely
• Non-permeable rocks within the drainage basin (water can infiltrate easily)
• The rainfall-very heavy in big droplets (less likely to infiltrate)
• Water table already very high (little scope for infiltration if ground is already saturated)
• Steep slopes in drainage basin (water flows downhill more rapidly causing less time to infiltrate)
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• Most important geologic agent in eroding, transporting and depositing sediments
• Nearly every landscape shows erosion or deposition
• Stream- a body of running water confined to a channel that runs downhill under the influence of gravity
1. Headwater- Upper part of stream near its source in the mountains
2. Mouth- A place where a stream enters sea, lake or larger stream
3. Channel- A long narrow depression eroded by a stream into rock or sediment
• Streambeds- bottom of the channel
• Stream banks- sides of the channel
4. Floodplains- flat valley floor composed of sediments deposited by the stream
5. Watershed- higher ridge of land, the boundary between one drainage basin and another
6. Source- The place where a river begins- river system has numerous sources
7. Confluence- A place where two rivers meet
Overground
• Channel flow- Raindrops might fall directly into a river or stream
• Surface Runoff- Water runs downhill over the ground towards a river or stream
1. Rain travelling as surface runoff will get to rivers and streams much more quickly, reaching a river or stream with little delay within a short time-span
2. More likely to flood with surface runoff
3. Surface runoff-> shorter lag time-> higher river peak discharge->more likelihood of flooding
Underground
• Raindrops infiltrates solid and rock. The water then moves underground towards a stream or river.
1. Water that infiltrates and travels underground travels much more slowly, finally reaching a river or stream bit by bit over a much longer period of time
Conditions that will make surface runoff more likely
• Non-permeable rocks within the drainage basin (water can infiltrate easily)
• The rainfall-very heavy in big droplets (less likely to infiltrate)
• Water table already very high (little scope for infiltration if ground is already saturated)
• Steep slopes in drainage basin (water flows downhill more rapidly causing less time to infiltrate)
•