Unit 8 B: The Rock Cycle, Water Cycle and Weathering Add the new notes to your table of contents, and then turn to the next clean page and set up your title and date

Add Rock Cycle to your index The Rock Cycle The rock cycle is the series of processes that change rocks from one form to another. Add Rock Cycle to your index

Some processes take place deep within Earth, while others, such as weathering and erosion, take place on or near Earth’s surface. The energy that drives the Rock Cycle comes from heat from the Earth’s core and Sunlight which drives weathering and erosion.

Igneous Rock: rock formed from magma or lava Sedimentary Rock: formed from layers of material (such as clay, sand, or mud) that is squeezed and cemented together Metamorphic Rock: formed when one kind of rock changes into another form due to extreme heat and pressure

Add water cycle to your index The water cycle is the continuous movement of water on, above, and below Earth’s surface. The energy that drives the Water Cycle comes from the sun. Add water cycle to your index

The water cycle goes through the processes of precipitation, evaporation and condensation. precipitation: any form of water that falls from the clouds and reaches Earth’s surface evaporation: the process by which water molecules in liquid water escape into the air as water vapor condensation: the process by which molecules of water vapor in the air become liquid water

https://www.youtube.com/watch?v=oaDkph9yQBs

Weathering and Erosion Weathering refers to the processes that break down rocks, changing Earth’s surface over time. Erosion is the moving of weathered material, or sediment, from one location to another. Add weathering and erosion to your index

Three agents cause weathering and erosion Water Wind Ice

Water The Grand Canyon was formed from the Colorado River running through, over time the river eroded the sides of the rock creating the canyon. The coastlines are eroded by water and are constantly changing.

Wind Strong winds also can erode and move sediment. Soil and rock that are not protected by plants can be eroded by wind.

Wind also can deposit sediment. Sand dunes are landforms made as wind continually moves and deposits sand grains. Tim McCabe/NRCS

Ice Frost wedging is what occurs when water in rocks freezes and melts repeatedly, breaking the rocks apart.

Large masses of ice, called glaciers, cause erosion by flowing down a mountain and removing rock and sediment. Erosion by glaciers makes deep valleys and steep peaks.

When glaciers melt, the water produced by the melting ice does not flow fast enough to carry sediment. Glacial deposits of sediment are called moraines.

The locations where sediment accumulates are called sedimentary basins. Sediment continues to be deposited in low areas and then forced upward as tectonic activity forms mountains.

Slowly but surely, weathering and erosion wear down mountains. Photo by Tim McCabe, USDA Natural Resources Conservation Service Dr. Parvinder Sethi

The process of breaking rock into small pieces without changing the composition of the rock is physical weathering. The process of changing the composition of rock and minerals by exposure to water and the atmosphere is called chemical weathering. Gases in the atmosphere can cause chemical weathering.

Physical weathering exposes more surface area of rocks, allowing more water and atmospheric gases to enter rocks. Chemical weathering weakens rocks by changing the composition of some minerals and dissolving others.

Soil consists of weathered rock, mineral material, water, air, and organic matter from the remains of organisms. Soil forms directly on top of the rock layers from which it is made and is the result of hundreds to thousands of years of weathering.

The roots of plants can grow into cracks in rock and eventually break the rock.

Soil formation begins when physical and chemical weathering break down rocks.

Soil formation begins when physical and chemical weathering break down rocks.

Warm, wet climates produce soil fastest. Large amounts of rain can speed weathering of rocks, and chemical reactions are faster in warmer temperatures.

The minerals and small pieces of rock produced by weathering are called sediment. Moving water causes erosion by picking up rock pieces and sediment, which scrape along the ground picking up more material.

Deposition is the process of laying down eroded material in a new location. If the speed of flowing water decreases, the water can no longer carry sediment and the sediment settles at the bottom of the water. Floodplains form when sediment settles out of rivers that flood the areas next to them.