Unit 4: Earth Systems & Recources

Convergent plates

Moving towards each other - results in mountains, earthquakes, volcanoes, island arcs

Divergent plates

Moving away from each other - result in sea floor spreading, rift valleys, volcanoes, earthquakes

Transform plates

Moving in opposite directions against each other (rubbing) - result in earthquakes

Soil Layer O

Organic surface layer - relatively undecomposed

Soil Layer A

Topsoil layer, rich in minerals and nutrients (humus), composed of decomposed organic material.

Soil Layer B

Subsoil - an accumulation of clay and silts from the horizon O and A, rich in minerals

Soil Layer C

Partly weathered parent material, sitting on top of bedrock

Sand

Large particles, poor water retention, but good drainage

Silt

Medium particle size, moderate water retention + drainage

Clay

Smallest particle size, high water retention, poor drainage

Loam

Mixture of sand, silt, + clay - Ideal conditions for agriculture

Layers of atmosphere from closest to farthest

Troposphere > stratosphere (increase in temp as alt. increase) > mesosphere > thermosphere (increase in temp as alt. increase, hottest layer) > exosphere