Weathering And Soil Flashcards
Chemical or mechanical?
Pollutants dissolve in water
Chemical
Chemical or mechanical?
Rock and water grind other rock
Mechanical
Chemical or mechanical?
Animals burrow into soil
Mechanical
Chemical or mechanical?
Intense temperature causes rocks to expand
Mechanical
Chemical or mechanical?
Ice expands cracks in rock
Mechanical
Chemical or mechanical?
Molecules combine and form oxides
Chemical
Chemical or mechanical?
Plants cause rocks to crumble
Mechanical
Explain the effects of mechanical weathering
Mechanical weathering breaks rocks into smaller pieces without changing their chemical makeup
Explain the effects of chemical weathering
Changes the materials that are part of a rock into new material.
The mechanical and chemical processes that change objects on Earth’s surface over time
Weathering
Ice wedging is to mechanical weathering as _______ is to chemical weathering.
Oxidation
_________ is to increased surface area as chemical weathering is to changed minerals
Mechanical weathering
Weathering is to water and temperature as _______ is to physical, chemical, and biotic factors
Environment
Acid rain is to _____ as abrasion is to mechanical weathering
Chemical weathering
Chemical and mechanical are to _______ as rain and snow are to precipitation
Weathering
Weathering caused by grinding away at rock
Abrasion
What animals do that break down rock
Burrowing
The process that changes minerals into new minerals
Chemical weathering
Weathering caused by plants and animals
Crumbling
Rain with a pH of 4.5 or less
Acid rain
Weathering caused by water that freezes
Ice wedging
All the space on the surface plane of an object
Surface area
The product of oxidation
Oxide
A measure of acidity
pH
Anything with a pH between 0 and 7
Acid
The chemical and physical processes that change objects in Earth’s surface over time are called ________
Weathering
Over thousands of years, _______ breaks up rocks into smaller pieces.
Weathering
During _______, physical processes break rocks into smaller pieces.
Mechanical weathering
Mechanical weathering does not change the _________ of the rock
Chemical makeup
When mechanical weathering breaks a large rock into smaller pieces, the total _________ of the rock increases
Surface area
Between sandy and clay soils, ________ soil holds more water and nutrients because it consists of smaller particles that have more surface area
Clay
In _______, water enters cracks in rocks and freezes. Water ________ when it freezes and makes the cracks larger.
Ice wedging
Expands
Grinding rock away by friction or impact is called _______.
Abrasion
________ growing in a crack in a rock and animals burrowing through loose rock can cause mechanical weathering
Plants
During _______, the materials that make up rocks are changed into new materials.
Chemical weathering
Water is an important agent of _______ weathering because most substances ________ in water
Chemical
Dissolve
A(n) _______ is a more powerful weathering agent than water.
Acid
The measure of acidity is called _____
pH
An acid has a pH less than ______
7
Rain weathers rock because rain is slightly _______
Acidic
_______ rain contains pollutants that make its pH less than 5.
Normal
Oxygen combines with other elements or molecules during _______
Oxidation
Most oxygen used in oxidation comes from the _____
Air
The product of oxidation is a(n) _______
Oxide
Oxides are useful because they form _______, which people use to obtain metals.
Ores
The _______ part of a rock oxidizes the most because it has more contact with oxygen in the air
Outside
Mechanical and chemical weathering depend on _____ and temperature
Water
Mechanical weathering occurs fastest in areas that have a lot of ________ changes
Temperature
Chemical weathering is fastest where the climate is warm and _______
Wet
Overall, weathering occurs fastest in regions near the _______
Equator
The type of ______ also affects how fast weathering occurs. The most easily weathered _______ in a rock determines how quickly the rock weathers.
Rock
Mineral
The shape of the land
Topography
The broken-down remains of dead plants and animals
Organic matter
All the living things in an area
Biota
The process that produces organic matter
Decomposition
Mixture of weathered rock, rock fragments, decayed organic matter, water, and air
Soil
The starting material that weathers and forms soil
Parent materiel
A small space in the soil
Pore
The average weather of an area
Climate
Rock material broken down or dissolved in water
Sediment
A layer of soil
Horizon
_______ is a mixture of weathered rock, decayed organic matter, mineral fragments, water, and air
Soil
About half the volume of soil is made of _____ materials
Solid
Soil also contains water, other liquids, and ______
Gases
In the soil, water and gases fill small holes called ______
Pores
_______ can flow through soil because pores are present.
Water
The movement of water through pores is called _______
Flow
The solid part of soil once part of living organism is ________
Organic matter
Organic matter forms when once-living material undergoes ________ by organisms in the soil
Decomposition
Organic matter helps hold water and ________ in the soil
Minerals
The ______ part of soil is made from materials, such as rock fragments, that have never been alive
Inorganic
There are five ______ of soil formation
Factors
The starting material of soil is called _______
Parent material
Parent material is made of the rock or ________ that forms soil
Sediment
The particle size and type of parent material can determine the _______ of the soil that develops
Properties
_____ is the average weather of an area. Soil can form rapidly in _____, wet climate
Climate
Warm
______ is the shape and steepness of the landscape
Topography
The ______ is all the organisms that live in a region. Some biota in the soil form passages for ______ to move through
Biota
Water
As time passes, weathering is constantly acting on _______ and sediment. Soil formation is a(n) ______ but slow process
Rock
Constant
______ are the layers of soil formed from the product of weathering
Horizons
There are _______ horizons common to most soils.
Three
The _______ is the soil you are most likely to see when you dig a shallow hole; it contains most of the organic material
A-horizon
The _______ usually contains a great deal of clay particles.
B-horizon
The ______ consists of parent material
C-horizon
The ______ of a soil determines the best use of the soil
pH
Plants depend on the _____ that come from organic matter and the weathering of rocks
Nutrients
There are _______ major soil types in the world
12
Soil type partly depends on _______
Climate
