Question | Answer |
What is igneous rock? When is it intrusive/extrusive? | formed by cooling of magma; extrusive = cooled rapidly at Earth’s surface and have small minerals, intrusive = cooled slowly underground and have large minerals |
form when rocks weather, erode, and are deposited/cemented into sedimentary rock, often contain fossils | sedimentary rock |
form when igneous or sedimentary rock is subjected to high heat and pressure | metamorphic rock |
hard inorganic substances composing rock | minerals |
Metallic minerals | include iron, aluminum, gold |
breaking of rock into smaller parts | weathering |
group of processes which produce rocks, gets energy from tectonic cycle | rock cycle |
rock weathers into small fragments combined with organic material from dead plants/animals forms soil | soil formation |
top soil | surface layer, typically rich in organic matter |
layer below surface layer, little organic matter | subsoil |
determined by amounts of sand, silt, and clay, if amounts of these three equal, called a loam | soil texture |
its particles are 0.2-2.0 mm diameter, water moves through rapidly, hence nutrient poor (washed out) | sand |
smaller than sand, moderate water and nutrient holding capacity | silt |
smallest soil particles, water moves slowly through, lots of nutrients | clay |
soil containing 40% sand, 40% silt, 20% clay, great for agriculture | loam |
porosity | amount of pore space (empty areas) between soil grains |
water logging | soil completely saturated with water, some plant roots can’t tolerate and plants die (fungus etc.) |
humus | organic (plant/animal remains), dark material remaining after decomposition by microorganisms |
humus containing pellets in soil from earthworms | castings |
illuviation | deposit of leached material in lower soil layers |