waterfall

Waterfalls are commonly formed when a river is young.At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens slowly, while downstream the erosion occurs more rapidly. As the watercourse increases its velocity at the edge of the waterfall, it plucks material from the riverbed. Whirlpools created in the turbulence as well as sand and stones carried by the watercourse increase the erosion capacity.^[1] This causes the waterfall to carve deeper into the bed and to recede upstream. Often over time, the waterfall will recede back to form a canyon or gorge downstream as it recedes upstream, and it will carve deeper into the ridge above it^. The rate of retreat for a waterfall can be as high as one and half meters per year.

A beach is a geological landform along the shoreline of an ocean, sea, lake or river. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles or cobblestones. The particles comprising the beach are occasionally biological in origin, such as mollusc shells or coralline algae.
Wild beaches are beaches which do not have lifeguards or trappings of modernity nearby, such as resorts and hotels. They are sometimes called undeclared, undeveloped or undiscovered beaches. Wild beaches can be valued for their untouched beauty and preserved nature. They are most commonly found in less developed areas including, for example, parts of Puerto Rico, Thailand, the Philippines, and Indonesia.
Beaches typically occur in areas along the coast where wave or current action deposits and reworks sediments.

Cliff

In geography and geology, a cliff is a significant vertical, or near vertical, rock exposure. Cliffs are formed as erosion landforms due to the processes of erosion and weathering that produce them. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually formed by rock that is resistant to erosion and weathering. Sedimentary rocks are most likely to form sandstone, limestone, chalk, and dolomite. Igneous rocks, such as granite and basalt also often form cliffs.

Natural resources

Natural resources occur naturally within environments that exist relatively undisturbed by mankind, in a natural form. A natural resource is often characterized by amounts of biodiversity and geodiversity existent in various ecosystems.

Natural resources are derived from the environment. Many of them are essential for our survival while others are used for satisfying our wants. Natural resources may be further classified in different ways.

There are various methods of categorizing natural resources, these include source of origin, stage of human use, and by their renewability, these classifications are described below. On the basis of origin, resources may be divided into:

Clasification

• Biotic – Biotic resources are obtained from the biosphere (living and organic material), such as forests, animals, birds, and fish and the materials that can be obtained from them. Fossil fuels such as coal and petroleum are also included in this category because they are formed from decayed organic matter.
• Abiotic – Abiotic resources are those that come from non-living, non-organic material. Examples of abiotic resources include land, fresh water, air and heavy metals including ores such as gold, iron, copper, silver, etc.