Weathering Basics
The process that changes rocks and other objects on Earth’s surface over time.
What is weathering?
The process where water enters cracks, freezes, and expands.
What is ice wedging?
This liquid is an important agent of chemical weathering.
What is water?
A mixture of weathered rock, organic matter, water, air, and minerals.
What is soil?
The topsoil layer where most organic matter is found.
What is the A-horizon?
This type of weathering breaks rocks into smaller pieces without changing their chemical makeup.
What is mechanical weathering?
The process of wearing down rock by friction or impact.
What is abrasion?
This kind of precipitation has a pH less than 5 and weathers rocks more strongly than regular rain.
What is acid rain?
The part of soil once part of living organisms.
What is organic matter?
This horizon contains mostly clay particles.
What is the B-horizon?
This happens to the total surface area when a rock breaks into smaller pieces.
What is it increases?
This soil type holds more water and nutrients due to its smaller particles.
What is clay soil?
This chemical reaction happens when oxygen combines with elements in rocks.
What is oxidation?
The process of water moving through pores in the soil.
What is porosity?
This horizon is made mostly of parent material.
What is the C-horizon?
The type of weathering where rocks are changed into new materials.
What is chemical weathering?
This can happen when a tree’s roots grow into cracks in rocks
What is mechanical weathering (caused by plants)?
This is what forms when oxidation occurs and is often mined for metals.
What is an oxide (or ore)?
This material weathers to form soil and affects its properties.
What is parent material?
Soil forms fastest in areas with this kind of climate.
What is warm and wet?
Two key factors that affect the rate of both chemical and mechanical weathering.
What are water and temperature?
Burrowing animals cause this type of weathering.
What is mechanical weathering?
This scale is used to measure the acidity of a substance.
What is the pH scale?
The living things in soil that help form passages and decompose material.
What is biota?
The overall process of soil formation is described this way.
What is constant but slow?