Streams and River Systems Flashcards
Streams
Flowing bodies of water confined within a channel, crucial for transporting water, sediment, and dissolved materials across the landscape
Current
The movement of water within a stream, influenced by velocity, discharge, and channel shape
Source
The origin or starting point of a stream or river, often found in highland or mountainous areas
Spring
A natural discharge of groundwater onto the Earth’s surface, often contributing to the base flow of a stream
Confluence
The point where two or more streams or rivers meet
Tributary
A smaller stream or river that flows into a larger one
Mouth
The end point of a river where it empties into a larger body of water like a sea, lake, or ocean
Estuary
A coastal area where freshwater from rivers mixes with saltwater from the sea, often rich in nutrients and biodiversity
Saltation
A form of sediment transportation where medium-sized particles bounce along the streambed
Traction
A process where larger sediments roll or slide along the bottom of the stream
Dissolved Load
The portion of a stream’s load carried in solution, typically minerals dissolved from rocks. These are invisible and contribute to water chemistry
Bank-Full Stage
The condition where a stream fills its channel completely before spilling over into the floodplain
V-Shaped Valleys
Narrow, steep-sided valleys formed primarily by river erosion in the upper course of a stream
Canyons
Deep, narrow valleys with steep sides, typically formed by long-term river erosion and tectonic activity
U-Shaped Glaciated Valleys
Valleys carved by glaciers with a characteristic U-shape, later possibly occupied by rivers or streams
Braided Streams
Streams with multiple intertwining channels, usually found in areas with high sediment load and variable discharge
Oxbow Lake
A curved lake formed when a meander is cut off from the main channel of a river
Rivers
Large natural streams of water flowing toward oceans, lakes, or other rivers
Divide
A geological barrier, such as a ridge or mountain, that separates adjacent drainage basins. Water on either side flows in different directions
Continental Divides
Major drainage divides on continents where water flows to different oceans
Dendritic Patterns
Tree-like drainage pattern formed on relatively uniform substrate, common in flat-lying sedimentary rock
Trellis Drainage
A drainage pattern that resembles a garden trellis, often developed on folded sedimentary rocks
Rectangular Patterns
A drainage pattern with right-angle bends, typically formed where joints or faults dominate the rock
Radial
A drainage pattern where streams radiate outward from a central point like a volcano or dome
Drainage Pattern
The spatial arrangement of streams in a region, shaped by the underlying geology. Common types include dendritic, trellis, rectangular, and radial
Drainage Basin
An area of land where all precipitation collects and drains off into a common outlet like a river. It includes all tributaries and stream channels
Factors Influencing Stream Velocity
Includes channel slope (gradient), water discharge, channel shape and size, roughness of the streambed, and obstructions like rocks or vegetation
Velocity Variation Within a Stream Channel
Water moves fastest in the deepest, central part of the channel and slower along the banks and bottom due to friction and obstructions
Suspension
Fine particles like silts and clays that are light enough to be carried within the water column, making streams appear muddy
