External processes
Weathering mass wasting and erosion are called?
on or near the earths surface and powered by the sun.
Where do external processes occur and and what are they powered by?
transforming solid rock into sediment
what are external processes responsible for?
Earth's interior
where do internal process derive their energy from?
Weathering
The physical breakdown and chemical alteration of rock at or near Earth's surface?
Mass wasting
The transfer of rock and soil downslope under the influence of gravity?
Erosion
The physical removal of material by mobile agents such as water, wind, or ice?
Weathering
How were many of the life sustaining minerals and elements found in soil and in foods we eat freed from solid rock?
Mechanical and chemical
What are the two types of weathering?
Mechanical weathering
What type of weathering is accomplished by physical forces that break rock into smaller and smaller pieces?
Chemical weathering
What type of weathering involves a chemical transformation of rock into one or more new compounds?
No
Does mechanical weathering change a rocks mineral composition?
frost wedging
expansion resulting from unloading
thermal expansion
biological activity
What four important physical processes lead to the fragmentation of rock?
frost wedging
What fragmentation process, works by water working its way into the cracks in rock, the freezing water enlarges the cracks and angular fragments are eventually produced?
Salt crystal growth
When sea spray from breaking waves or salty ground water penetrates crevices and pore spaces in rock. As this water evaporates, salt crystals form.
Sheeting
When large masses of igneous rock, are exposed by erosion, concentric slabs begin to break loose, and resemble onion like layers?
Granite
What type of rock does sheeting typically happen in?
Unloading
Great reduction in pressure when the overlying rock is eroded away?
Exfoliation domes
Created by unloading, continued weathering causes the slabs to separate and spall off?
Joints
Important rock structures that allow water to penetrate to depth and start the process of weathering long before the rock is exposed?
Expansion
Heating a rock causes what?
Contraction
Cooling a rock causes what?
Water
What is the most important agent in chemical weathering?
Dissolution, oxidation, and hydrolysis
3 major processes of chemical weathering?
Dissolution
What is the process of dissolving water?
insoluble
Most minerals are _______ in pure water?
Oxidation
Occurs when electrons are lost from one element during the reaction?
Hydrolysis
The most abundant mineral group, the silicates is decomposed primarily from what process?
Hydrolysis
The reaction of any substance with water?
Hydrogen ions
With the introduction of ___________into the crystalline structure, the original orderly arrangement of atoms is destroyed and mineral decomposes?
carbonic acid
In water___________ionizes to form hydrogen ions and bicarbonate ions?
Quartz
Other main component of granite, is very resistant to chemical weathering?
Spheroidal weathering
Gives the weathered rock a more rounded or spherical shape?
Rock characteristics
encompasses all of the chemical traits of rocks, including mineral composition and solubility?
Climate factors
are important, particularly temperature and moisture, are crucial to the rate of rock weathering?
Differential weathering
The variation in the rate and degree of weathering caused by such factors as mineral makeup, degree of jointing, and climate.
Regolith
The layer of rock and mineral fragments produced by weathering?
Soil
Is a combination of mineral and organic matter, water, and air that portion of the regolith that supports the growth of plants?
Humus
Decayed remains of animal and plant life.
Disintegrated and decomposed rock and hums
About one half of the total volume of a good quality surface soil is a mixture of?
Pore spaces of air and water
What does the second half of good quality soil consist of?
Mineral portion
which portion of soil is usually MUCH greater?
NO
Is soil water pure?
pore spaces
allow the circulation of fluids in soil?
air
pore spaces not filled with water are filled with?
Parent material
time
climate
plants and animals
topography
soil is the product of the complex interplay of these factors?
parent material
Source of the weathered mineral matter from which soils develop?
residual soils
When the parent material is bedrock the soil is termed?
Transported soils
Parent materials that develop on unconsolidated sediment are called?
Time
the longer a soil has been forming the the thicker it becomes and the less it resembles the parent material? which factor of soil?
climate
considered to be the most influential control of soil formation?
Temperature
precipitation
variations in _________and _________ determine whether chemical or mechanical weathering will predominate?
Plants
Primary source of organic matter in soil comes from what?
Topography
Affects soil types by the length and steepness of slopes. This has an impact on the amount of erosion and the water content of soil?
Slope orientation
The direction the slope is facing?
Solum
True Soil?
Soil Taxonomy
A system for classifying soils?
Soil erosion
natural process, it is part of the constant recycling of Earth materials?
Sheet erosion
Because soil is moved by thin sheets of water, this process is termed?
Flowing water
It is estimated that about two-thirds of the soil erosion in the U.S is done by what?
Lithosphere and the biosphere, atmosphere and hydrosphere.
Soil forms at interface between what?
Aridolosols
One type of soil from the soil taxonomy chart is Nevada's soil?
NO
Is soil a renewable resource?
Calcite
What mineral is a major factor in "cemented soil"?