Earth Science Lecture Notes

Flashcards for Earth Science Exam Review

Mantle convection

Heat from Earth's core causes molten rock to rise and sink, moving plates.

Earth's layers (in order)

Crust, Mantle, Outer Core (liquid), Inner Core (solid)

Outer Core

Layer is liquid because it's so hot the metals are molten.

Convection currents

Hot material rises, cools, sinks—cycle moves plates.

Plate tectonic theory

Explains plate movement.

Divergent Boundary Processes

Earthquakes, seafloor spreading, volcanic activity

Divergent Boundary Features

Mid-ocean ridge, rift valley

Convergent Boundary Processes

Earthquakes, volcanic activity, subduction

Convergent Boundary Features

Mountains, trench, volcanoes

Transform Boundary Processes

Earthquakes

Transform Boundary Features

Fault lines (like San Andreas)

Seismic waves

Energy from earthquakes.

P waves

Fast, move through solids/liquids.

S waves

Slower, only solids.

Hotspots

Hot mantle plumes that burn through crust (e.g., Hawaii).

Hawaii formation

Plate moves over a hotspot—new islands form over time.

Oceanic vs Continental crust

Oceanic = denser → sinks under continental → subduction.

Caldera

Collapsed volcano after major eruption

Rock cycle

Continuous process where rocks change into other types (igneous, sedimentary, metamorphic).

Igneous rock formation

Cooling of magma/lava.

Sedimentary rock formation

Compacted sediments.

Metamorphic rock formation

Heat & pressure.

Weathering

Breaks rock.

Erosion

Moves rock.

Deposition

Drops sediments.

Compaction/Cementation

Forms sedimentary rocks.

Melting/Cooling

Igneous rock formation.

Heat/Pressure

Metamorphic rock formation.

Physical weathering

Breaks rock (ice, wind).

Chemical weathering

Changes composition (acid rain).

Soil composition

Weathered rock, minerals, water, air, and organic material.

Factors affecting soil formation

Parent rock, climate, topography, time, organisms.

O Horizon

Organic (leaves)

A Horizon

Topsoil

B Horizon

Subsoil

C Horizon

Weathered rock

R Horizon

Bedrock

Importance of soil

Grows crops, filters water, supports life.

Soil conservation

Crop rotation, cover crops, terraces, no-till farming.

Land use

How humans use land (farming, cities, mining).

Urbanization effects

More runoff, less biodiversity, habitat loss, heat islands.

Deforestation

Cutting down trees.

Sustainable land use

Using land without harming future use (reforestation, eco-friendly farming).

Weather

Short-term.

Climate

Long-term average.

Factors affecting climate

Latitude, elevation, proximity to water, ocean currents.

Greenhouse effect

Gases trap heat in the atmosphere—natural but worsened by humans.

Biosphere

All living things on Earth.

Biomes

Large ecosystems (desert, forest, tundra) defined by climate & life.

Protect biodiversity

Conservation, protected areas, laws.

Hydrosphere

All water on Earth (liquid, ice, vapor).

Freshwater percentage

Only 3% of Earth’s water is freshwater.

Water cycle steps

Evaporation, Condensation, Precipitation, Infiltration, Runoff

Factors affecting water availability

Climate, pollution, overuse, drought.

Protecting water

Reduce waste, protect wetlands, clean up pollution.

Fossil fuels

Coal, oil, gas—nonrenewable, polluting.

Ecological footprint

Amount of land/water needed to support a lifestyle.