Destructive Force: Weathering The process of breaking down of rocks and land due to forces such as gravity, wind, water and ice. When it rains, rocks are washed down a mountain or down a stream. Soils are washed away. The ocean beats against a cliff and breaks it apart.

moving water

The three main forces that cause erosion are water, wind, and ice. Water is the main cause of erosion on Earth.

Physical erosion often causes rocks to get smaller or smoother. Rocks eroded through physical erosion often form clastic sediments. Ice and liquid water can also contribute to physical erosion as their movement forces rocks to crash together or crack apart. Some rocks shatter and crumble, while others are worn away.

Land forms are the result of a combination of constructive and destructive forces. Constructive forces include crustal deformation, volcanic eruption, and deposition of sediment, while destructive forces include weathering and erosion.

Destructive forces wear landforms down. The slow processes of mechanical and chemical weathering and erosion work over time to change once high mountains into smooth flat plateaus.

Forces That Cause Landforms The daily processes of precipitation, wind and land movement result in changes to landforms over a long period of time. Driving forces include erosion, volcanoes and earthquakes.

Pacific Ocean

Sinkholes can be very destructive, but they are rarely deadly.

There are basically four (4) different types of sinkholes in Florida.

• Collapse sinkholes. This occurs in areas where there is extensive cover materials over a limestone layer.
• Solution Sinkholes.
• Alluvial Sinkholes.
• Raveling sinkholes.

Cover-collapse sinkholes

What are the warning signs?

• Fresh cracks in the foundations of houses and buildings.
• Cracks in interior walls.
• Cracks in the ground outside.
• Depressions in the ground.
• Trees or fence posts that tilt or fall.
• Doors or windows become difficult to open or close.
• Rapid appearance of a hole in the ground.

Xiaozhai tiankeng

Sinkholes are just one of many forms of ground collapse, or subsidence. Land subsidence is a gradual settling or sudden sinking of the Earth’s surface owing to subsurface movement of earth materials. A sinkhole is a depression in the ground that has no natural external surface drainage.

Sinkholes may occur along outside walls or in the lawn or garden. They can have various shapes and sizes and can grow or deepen either slowly or rapidly. In many cases, sinkholes can be repaired by the homeowner. Before any remediation work is done, the extent and cause of the sinkhole should be determined.

The best way to explain it, from the Florida Environmental Department website, a sinkhole is a type of depression, but not all depressions are sinkholes.

The sinkholes destroyed homes, roads and sections of cultivated areas. Sinkholes are common where the rock below the land surface is limestone, carbonate rock, salt beds, or rocks that can naturally be dissolved by groundwater circulating through them.

When a sinkhole forms, water will start pooling on the ground. Trees and fence posts will start to tilt or fall over. The vegetation might wilt and die due to the sinkhole draining away water.

Sinkhole risk The actuarial risk of a catastrophic sinkhole happening is low—researchers put it at a one-in-100 chance of occurring in any given year. The U.S. Geological Survey says there is not yet an efficient system to determine if there is—or isn’t—a sinkhole on your property.

Human activity can create sinkholes, too, for example, via collapsed or broken sewer and drain pipes or broken septic tanks, improperly compacted soil after excavation work, and buried trash, logs and other debris. They can also occur from the overpumping and extraction of groundwater and subsurface fluids.

“The most damage from sinkholes tends to occur in Florida, Texas, Alabama, Missouri, Kentucky, Tennessee, and Pennsylvania.”

Does Homeowners Insurance Cover Sinkholes? Most standard homeowners insurance policies exclude coverage for sinkhole formation. Homeowners policies are generally valued based on the cost to rebuild the physical structure of your home. The value of the land on which your home is built usually isn’t covered.