Weathering refers to the breaking down and erosion of rocks and minerals on Earth’s surface, while transport is used to move those particles that have become weathered to another location.
Deposition occurs when eroded material drops off into new landforms and forms new landforms, giving geologists insight into its erosional process through characteristics like rounding: sharp corners are more likely in angular sediment while smooth-edged pieces often have rounder corners.
Water
Water’s movement is one of the primary forces at work in weathering erosion deposition. Rain, waves, ice and wind all play their parts in creating physical weathering of rocks and materials making up Earth’s surface.
Water can freeze and thaw rock, causing it to fracture and crumble over time, eventually becoming large enough for it to break apart into smaller pieces called sediment.
River water flows rapidly downstream, dislodging sediment from its bed. Over time, this erosion-deposition process creates special geological features such as canyons.
Minerals that score high on Bowen’s Reaction Series tend to chemically weather more quickly than minerals with lower scores, while harder rock types like granite and gabbro tend to weather more slowly than softer volcanic rocks. One indicator of physical weathering occurs is rounding sediment grains; more rounded grains indicate increased erosion over an extended period or transport distance; such rounding is indicated by flute casts, groove casts and tool marks in their vicinity.
Ice
Weathering refers to the process of breaking down rocks and materials on Earth’s surface through natural forces such as weathering. Erosion refers to when these broken-down pieces of rock are moved around by wind, water and ice forces before eventually depositing elsewhere in a different location.
Weathering caused by natural processes of freezing and thawing can also contribute to weathering. Rainwater seeping through cracks in rocks can freeze into expansion cracks that then freeze again as the temperature fluctuates; this process is known as “ice wedging”. Over time, repeated cycles of this weathering cause rocks to loosen from each other, eventually dismantling the rocks completely – often leaving potholes behind on road sides or sidewalks.
Plants can also contribute to weathering by growing in cracks in rocks and soil, where their roots will then pull apart the rock face, creating mechanical weathering or root wedging effects which, over time, wear away at mountains; although this process takes many thousands of years.
Wind
Weathering and erosion are widespread processes–from cracks in sidewalks to beach sand shifting along beaches to rocks sliding off mountains. These natural processes can happen fast or slowly: for instance mudslides or river erosion might move rocks quickly downward while plant roots wedge between cracks in rock, glaciers move slowly downhill, or living organisms break off pieces of rock while eating algae.
Wind can erode rock by blowing or dragging away particles and transporting them across surfaces, particularly in arid regions where particles of silt or clay may travel long distances – these particles are known as bed load and suspended load respectively.
Erosion is the process of moving pieces of Earth’s surface away from their original locations through water, wind, ice (glaciers), and gravity; its main forces being water, wind, ice (glaciers), and gravity. Once these particles have been moved by erosion they become known as sediments; deposition involves depositing these sediments onto landscapes.
Earth’s Rotation
The Earth rotates or spins counterclockwise. Although this movement is invisible to us humans, its impact is immense on geological processes such as weathering, erosion and deposition.
Mechanical weathering involves breaking rocks down without altering their chemical nature, typically in environments with an abundance of water as the liquid dissolves minerals present within rocks.
Erosion transports the rocks and soil left behind after weathering to new locations through erosion, usually with liquid having high kinetic energy like flowing water or ice.
Erosion may be caused by natural forces such as wind or gravity or by humans through using tools like glaciers (see Chapter 10). Sedimentation converts loose rock particles into clastic sedimentary rock through three interrelated steps; mechanical compaction involves when layers of sediment build up against themselves and compress against each other before being compacted against themselves further by compression forces.