Rivers

Earth Science

Sediments

• Graded bedding

Sediments

• Laminations

Sediments

• Laminations

Sediments

• Ripple Marks -- asymmetrical

Sediments

• Ripple Marks -- symmetrical

River Sediments

• Crossbedding

Sediments

• Mudcracks

Sediments

• Mudcracks

Flood Plains

• Provide a water reservoir during flooding

• Provide residence time

Drain Patterns

• Dendritic

Drain Patterns

• Dendritic– Result of water flowing across loose,

unconsolidated sediment or soil

Drain Patterns

• Radial

Drain Patterns

• Radial– Results from water flowing from a dome or hill

Drain Patterns

• Rectangular

Drain Patterns

• Rectangular– Faulted or fractured rock

Drain Patterns

• Trellis

Drain Patterns

• Trellis– Tilted or folded rock

Drain Patterns

• Dendritic

• Radial

• Rectangular

• Trellis

Deltas

• Tributaries

• Distributaries

Delta Types

• Lobate

Delta Types

• Lobate– Large amounts of sediment– Weak or disorganized ocean currents

Delta Types

• Lobate -- Mississippi

Delta Types

• Arcate

Delta Types

• Arcate– Low sediment – Strong, single-direction ocean current

Delta Types

• Arcate -- Nile

Delta Types

• Cuspate

Delta Types

• Cuspate– Moderate sediment– Strong, two-directional ocean current

Delta Types

• Cuspate -- Tiber

Delta Types

• Estuarine

Delta Types

• Estuarine –– Colorado

Delta Types

• Lobate

• Arcate

• Cuspate

• Estuarine

Superposition

• The Grand Canyon is a result of the uplift of the land where the Colorado River runs.