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Geologic Monitoring

Marine Features and Processes

Carlsbad Caverns
High frequency profilers give high resolution data of the shallow subbottom. Photo courtesy of Sea Surveyor, Inc.

What are marine features and processes?

For the purpose of our discussion here, marine refers to those features and processes occurring seaward from the low tide line. Beach features and processes are covered here.

Marine features include:
Marine processes include:
  • waves
  • tides
  • ocean currents
  • sea level changes

Why does the National Park Service monitor nearshore marine features?

The nearshore, or submarine, landscape is closely tied to the onshore landscape of beaches and dunes that most commonly come to mind when we think of the coast. The morphology of the nearshore environment exerts a major control on the magnitude of storm surge and coastal flooding that will be caused by the passage of a hurricane or winter storm. Offshore hardgrounds may actually protect portions of the coast from erosion.

Monitoring nearshore marine features helps the National Park Service to understand the dynamics of coastal areas and better respond to environmental stressors such as, storms and sea level changes

  • Monitoring Book
  • Resource Facts
  • Case Study

Geological Monitoring Book

Vital Signs Monitored

  1. Bathymetry
  2. Hydrography
  3. Barriers: reefs
  4. Barriers: other
  5. Substrate
  6. Water column

Chapter 7
Marine Features and Processes (PDF - 2.28MB)

Marine environments include anything seaward of the shoreline, the dividing line between land and water. For the purposes of this chapter, marine features and processes will be considered seaward from the low tide line-that is, the beginning of the shoreface. The nearshore marine system can be subdivided into the water column and the seafloor. More than just waves, the nearshore zone is also acted upon by tides, ocean currents, sea level changes, sedimen supply, and biologic effects.

It is certainly beyond the scope of any manager to monitor every aspect of the nearshore zone. Some important aspects, though, that can be easily observed and monitored include bathymetry of the nearshore, hydrography (waves and tides and perhaps currents), reefs (if applicable), other offshore barriers (sand bars), substrate, water column turbidity, and water column chemistry and quality.

NPS Marine Resource Facts

The NPS manages 84 ocean and Great Lakes parks across 26 states.

There are approximately 2.5 million acres of water contained within the 84 ocean, coastal and Great Lakes parks.

Monitoring Marine Features and Processes in the National Park Service

Monitoring Coral Reefs in U.S. National Parks: A Snapshot of Status and Trends in Eight Parks

Percent cover:the amount of reef area occupied by live coral
Rugosity:a measure of a coral reef's three-dimensional structure
Coral bleaching and disease:the amount of coral that is bleached or diseased
Coral recruitment:a measure of the number of juvenile corals settling on a reef

More information:Shoreline Change Monitoring at Assateague Island National Seashore, 2005-2010 Trend Report (PDF - 10.5 MB)

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Last Updated: January 03, 2017