Coastal, Glacial, and Karst Landform Processes

Seawater: Coastal Modeling

Retreating Cliff Processes

Waves erode the bottom of cliffs, leading to falling blocks. This process produces a surface that can be partially exposed at low tide, known as an abrasion platform.

Crushing and Washing Materials

Rock blocks and fragments are shredded through crushing and washing.

Transport and Coastal Sedimentation

Sand is transported by currents along coastlines to more sheltered areas, creating:

• Beaches: Accumulations of sand or gravel in areas where the shoreline has a gentle slope.
• Raffles and Arrows: Sandy strands, perpendicular or parallel to the coast, that tend to isolate small lagoons and coastal marshes.

Glaciers: Modeling Glacier Action

Glacial Movement

Glaciers consist of large ice masses that flow slowly under their own weight, capable of eroding the soil.

Erosive Features

• U-Shaped Valleys: Wide valleys with a deep, rounded profile.
• Overdeepening Zones (Sobreexcavacion Zones): Cavities produced by flowing ice.

Transport and Glacial Sedimentation

Sedimentation occurs as Tillite (Claster accumulations produced by glaciers), known as moraines.

Karst Modeling

Water Dissolution

Surface and underground waters have the capacity to dissolve rock.

Surface Erosive Forms

• Solution: Rainwater running over rocks produces soluble grooves called sinkholes.
• Collapse: Occurs when the roof of a subterranean cavity (a doline or sinkhole) collapses.

Groundwater Erosive Forms

• Galleries: More or less horizontal tunnels; when they are closer together, they are called Galerías (Gateras).
• Potholes: Vertical ducts that sometimes reach the surface.
• Halls: Large, irregularly shaped cavities.

Karst Sedimentation

• Accumulation of Decalcification Clay: Clay remains as waste after the dissolution of calcium from limestone.
• Precipitation of Soluble Salts: Dissolved calcium carbonate can precipitate, forming travertine.

Conditioning Factors in Modeling

Climate

Landform development is climate-dependent:

• Warm-Arid Areas: Lack glaciers and significant rivers.
• Temperate and Wet Areas: Feature abundant vegetation.
• Polar or High Mountain Areas: Water remains predominantly as ice.

Tectonic and Structural Factors

• Rivers move along faults.
• Glacier tongues become embedded where fractures exist.
• Ground uplift causes rivers to recover energy.

Lithologic Factors

• Soft materials are easily eroded.

Anthropic Factors