reading quiz ch 13 #1

Rivers can be described by certain key terms. Match the terms to their definitions: 1. base level 2. load 3. discharge 4. gradient 5. sinuosity ___ level of river at its mouth ___ amount of flow over a given time interval ___ change in height over a distance ___ amount of "waviness" in the stream ___ amount of material carried by the flowing water

1 3 5 4 2

Rivers can alter their shapes to balance the discharge with the gradient. For the processes below, determine whether the river is responding to too much gradient or too little gradient. 1. too little gradient 2. too much gradient -increasing meandering -decrease slope -carry extra sediment (braiding) -erode dam

2 1 2 1

Factor(s) that interact to make streams seek equilibrium include the __________. volume of water discharged by the stream amount of sediment waiting to be moved slope of the stream bottom sinuosity of the stream path All of these choices are correct.

All of these choices are correct.

In this diagram a stream fills the lake with sediment and then flows across the sediment-filled lake. When the stream tops the dam's steep face at high velocity, erosion and transport of dam and lake sediment. Label the parts that support this action. -lake filled by stream sediment -stream bottom -landslide dam

Figure 13.11 -stream bottom -lake filled by stream sediment -landslide dam

As streams mature they overflow their banks and meander to produce floodplains that become the stream floors during floods. Label the diagram to show the parts of the floodplain. -bedrock -floodplain -floodplain deposits -river channel

Figure 13.12 -floodplain -river channel -floodplain deposits -bedrock

Label the following figure with the key terms that describe a stream's flow. -cut bank -point bar -Min V -Max V

Figure 13.8 point bar Min V Max V cut bank

If a stream has too much load the excess sediment will be dropped on the steam bottom which will increase the gradient and increase the speed of river flow. Label the parts of the diagram that support this statement -stream bottom after deposition -too much load -stream bottom

Figure 13.9 -stream bottom after deposition -stream bottom -too much load

If a flood has a recurrence interval of ten years, it means that __________. a similar-sized flood will occur once every ten years a similar-sized flood has a greater probability of occurring every tenth year than during any one of the intervening years in any given year a similar flood has a 1/10 chance of occurring the flood must be bigger than any other flood during any given 10-year interval None of these choices are correct.

in any given year a similar flood has a 1/10 chance of occurring

If a stream has a meandering section, that section is most likely to be __________. in its upstream section near its source or sources in its downstream section, near its mouth in its upstream section near its source or sources or in its downstream section, near its mouth braided

in its downstream section, near its mouth

Base level __________. is the level below which a stream cannot erode for all streams is sea level is the average annual flow level for a stream is the minimum amount of flow possible for a stream is elevation of the groundwater where the stream is flowing

is the level below which a stream cannot erode

On a given stream, small floods happen __________. with the same frequency as large floods more often than large floods less often than large floods, which explains why we hear about large floods more often in the news sometimes more often, sometimes less often than large floods, depending on long-term climate

more often than large floods

If a stream experiences more energetic water flow, the stream __________. responds by increasing the sinuosity of its channel pattern through meandering responds by decreasing the sinuosity of its channel pattern will not change its sinuosity, but will erode sediment will not change its sinuosity, but will deposit sediment will not change its flow path

responds by decreasing the sinuosity of its channel pattern

If a stream is choked with sediment and has insufficient water to carry it away __________. the water will pick its way through as a braided stream a peninsula is formed a canyon is formed a flood will occur Any of these choices may happen.

the water will pick its way through as a braided stream

A braided stream has __________. too much sediment to carry too little sediment in suspension, causing erosion in a braided pattern no relationship to the amount of sediment being transported a sediment load equal to the amount of sediment it can transport

too much sediment to carry