(TEST 1) Earth Science, Lecture pt 2 (ch 3) Flashcards
What are the three broad classifications of rocks?
Igneous
Sedimentary
Metamorphic
What is a sediment?
Loose fragments of rocks or minerals broken off bedrock
How are sediments produced?
Through weathering
What is weathering?
The physical or mechanical and/or chemical breakdown of pre-existing rocks
What is physical weathering?
The breakdown of intact rock into unconnected clasts (grains or rock fragments)
What are the three ways which rocks can be physically weathered?
- Abrasion
- Jointing
- Wedging
What is abrasion?
Breakdown of rocks due to material falling or washing down slopes
What is jointing?
Natural cracks that form in rocks due to the removal of overburden or due to cooling
What is exfoliation jointing?
A type of jointing where rocks can break into thin sheets along pre-dominantly flat-lying parallel joints
What is wedging?
Expansion slowly forces open cracks in rocks
What are the types of wedging?
Frost wedging
Salt wedging
What is chemical weathering?
The decomposition of minerals in rocks via chemical reactions
What are the types of chemical weathering?
- Dissolution
- Hydrolysis
- Oxidation
What is dissolution?
Dissolving of minerals into water
What is hydrolysis?
A reaction between water and mineral in which water itself is broken down (typically into a weak acid)