Sediment acquired by a stream is then transported through the channel network along sections referred to as trunk streams. When trunk stream are in balance, the amount of sediment eroded from their banks equals the amount deposited elsewhere in the channel. Although trunk streams rework their channels over time, they are not a source of sediment nor do they accumulate or store it.
When a river reaches the ocean, or another large body of water, it slows and the energy to transport sediment is greatly reduced. Most of the sediments either accumulate at the of the river to form a delta, are reconfigured by wave action to form a variety of coastal features, or are moved far offshore by currents. Because coarse sediments tend to be deposited upstream, it is primarily the fine sediments (clay, silt, and fine sand) that eventually reach the ocean. Taken together, erosion, transportation , and deposition are the processes by which rivers move Earth's surface materials and sculpt landscapes.
The ability of a steam to erode and transport material is directly related to its flow velocity.
Even slight variations in flow rate can lead to significant changes in the sediment load transported by a stream. Several factors influence flow velocities and, therefore, control a stream's potential to do "work. These factors include (1) channel slope or gradient; (2)channel size and cross sectional shape: (3) channel roughness; and(4) the amount of water flowing in the channel
Sediment acquired by a stream is then transported through the channel network along sections referred to as trunk streams. When trunk stream are in balance, the amount of sediment eroded from their banks equals the amount deposited elsewhere in the channel. Although trunk streams rework their channels over time, they are not a source of sediment nor do they accumulate or store it. When a river reaches the ocean, or another large body of water, it slows and the energy to transport sediment is greatly reduced. Most of the sediments either accumulate at the of the river to form a delta, are reconfigured by wave action to form a variety of coastal features, or are moved far offshore by currents. Because coarse sediments tend to be deposited upstream, it is primarily the fine sediments (clay, silt, and fine sand) that eventually reach the ocean. Taken together, erosion, transportation , and deposition are the processes by which rivers move Earth's surface materials and sculpt landscapes. The ability of a steam to erode and transport material is directly related to its flow velocity.Even slight variations in flow rate can lead to significant changes in the sediment load transported by a stream. Several factors influence flow velocities and, therefore, control a stream's potential to do "work. These factors include (1) channel slope or gradient; (2)channel size and cross sectional shape: (3) channel roughness; and(4) the amount of water flowing in the channel
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