Estuaries

Based on the diagram showing a fjord-type estuary, which feature most directly explains its long, narrow, and deep shape?

• Barrier islands that shield the coastline

• River deltas depositing sediment

• Glacial erosion carving steep-sided valleys

• Tectonic uplift forming coastal terraces

A back-barrier estuary like the Brigantine Estuary is most likely to experience which change after prolonged heavy rains according to the diagram?

• Barrier beaches grow larger and block the estuary permanently

• Small bars can be washed away, reopening the mouth of the estuary

• Waves bypass barrier islands and become stronger inside the estuary

• Glaciers advance and deepen the estuary basin

Tags

NGSS.HS-ESS2-5

Which statement best describes how a tectonic estuary can form?

• Sea level rises and floods a river valley without tectonic activity

• Earthquake-related faulting creates depressions that may fill with ocean water and receive freshwater from rivers

• Barrier islands form and block the coastline, trapping water behind them

• Glacial carving produces deep, U-shaped valleys that later fill with seawater

San Francisco Bay is identified in the material as an example of which type of estuary?

• Coastal plain estuary

• Bar-built estuary

• Fjord

• Tectonic estuary

In a salt wedge estuary, what causes the distinct wedge of saltwater at the bottom?

• High tidal range pushes saltwater uniformly throughout the water column

• Fresh, low-density river water flows over incoming denser saltwater

• Wind-driven mixing that stratifies the water by temperature

• Upwelling brings cold, salty water to the surface

Based on circulation patterns, in which setting would a salt wedge be most likely to develop?

• Small, slow rivers with high tidal range

• Large, fast-flowing rivers entering the ocean with low tidal range

• Coastal embayments dominated by wind mixing

• Glacial fjords with strong tidal currents

Tags

NGSS.MS-ESS2-6

Which feature most distinguishes fjord estuaries from other estuary types due to their glacial origin?

• Broad, sandy deltas

• Shallow lip or sill at the mouth with steep-sided valleys

• Extensive mangrove forests

• Large tidal flats formed by river deposition

A glacier retreats from a coastal valley, leaving a deep, steep-sided basin with a shallow sill at the entrance. Which classification best fits the resulting estuary, and why?

• Coastal plain estuary, because it forms from drowned river valleys

• Bar-built estuary, because it is isolated by sand bars

• Fjord estuary, because glacial carving creates steep sides and a shallow entrance sill

• Tectonic estuary, because faulting creates basins

Tags

NGSS.HS-ESS2-2

Which feature most directly creates the protected lagoon typical of a bar-built estuary?

• A deep river valley carved by glaciers

• A sand bar or barrier island that forms offshore

• A tectonic uplift that raises coastal cliffs

• A coral reef growing near the shoreline

Tags

NGSS.HS-ESS2-5

A coastal region contains an estuary behind a long, narrow barrier island. Local planners expect strong storm waves over the next decade. Which management priority best reflects the vulnerability and function of this bar-built estuary?

• Increase shipping traffic to maximize port revenue

• Dredge the lagoon regularly to remove all sediment

• Protect the barrier island and sand bars to maintain the estuary’s shielding role

• Replace salt marshes with bulkheads to prevent flooding

Tags

NGSS.HS-ESS2-2

NGSS.HS-ESS3-1

NGSS.HS-ESS3-4