refers to the process of breaking down of rocks into smaller pieces called sediments.
Weathering
a process wherein rocks are broken down into smaller pieces without changing their chemical composition
Mechanical weathering
a process wherein rock materials are changed into other substances that have different physical and chemical compositions.
Chemical weathering
involves repeated cycles of freezing and thawing of ice. One of the accepted explanations about this process is the expansion of water as it freezes.
Frost Wedging
Heating and Cooling
Rocks are composed of different minerals which expand and contract when subjected to sudden changes in temperature. The constant cycle of expansion (due to heating) and contraction (due to cooling) eventually causes rocks to fracture and break down into smaller pieces. Rocks in highways develop cracks and small fractures because of too much exposure to heat.
Salt Crystal Growth
his process happens when seawater penetrates crevices in rocks which are found mostly in rocky shorelines and arid regions. Salt crystals are left in pore spaces of the rocks when seawater evaporates. These salt crystals continue to grow larger as more saline water enters and evaporates.
Biological Activity
action of organisms including plants and animals reduces the size of rocks and minerals which make rocks more susceptible to chemical weathering. Plant roots, for example, cause rocks to wedge as it penetrates the cracks in search of water and nutrients.
a constant recycling of Earth’s materials under the rock cycle.
Erosion
a type of erosion where water carries the sediments to different bodies of water such as rivers.
Water erosion
happens when light materials, such as small rocks and pebbles, are carried by the wind to different places
Wind erosion
the process of deposition once the sediments are transported.
Sedimentation
mass wasting
the movement of sediments due mainly to gravity.
- does not need any transporting medium such as wind, water, or glacial ice.
is defined as molten rock material produced by partial melting of the mantle and crust. It contains liquids, gases, crystals and rock fragments. The amounts of these components depend on the temperature and pressure conditions during the formation.
Magma
occurs along plate boundaries or margins and sometimes within the plate. Cracks on Earth’s crust are the result of these plate boundaries.
Magmatism
is the process where magma rises to the surface of Earth as lava. From human perspective, it can be viewed as a destructive event as it could damage infrastructures, cause injuries and short-term climate change.
volcanism
a hill or mountain where lava, pyroclastic materials, and gases erupt. It can form along plate boundaries or within the plate.
volcano
divergent plate boundaries
volcanism manifests as ridges or fissures where products of decompression melting erupt.
convergent plate boundaries
host large number of volcanoes. Lava flows and pyroclastic materials make up these volcanoes. Here, subduction melting forms elongated chains of volcanoes following the shape of the trench, called volcanic or island arcs.
Endogenic Forces
- These are internal forces that exist deep inside the Earth.
- These forces are also known as ‘constructive forces’ as they create relief features on the surface of the Earth.
- The ultimate source of energy behind forces that drive endogenic movements is earth’s internal heat.
Exogenic Forces
- These are external forces that operate and act on the surface of the Earth.
- These forces are also known as ‘destructive forces’ as they at times result in destruction of the existing landforms through weathering and erosional activities.
- Weathering, mass wasting, erosion, and deposition are the main exogenic processes.
