Megan GardnerSamson UrbanDianna Cardenas

THE SOLID EARTH

THE SOLID EARTH

The Earth’s Formation and Structure• Formed approximately 4.6 billion years ago from a nebular cloud.• Eventually, the earth formed five different layers: inner core, outer core, mantle, crust, and the atmosphere.

Earth Structure Vocabulary• Planetesimals: large clumps of solid material several kilometers in diameter• Core: made up of two parts; the solid inner core and the liquid outer core• Mantle: Largest layer in the earth made up of asthenosphere and magma (i.e., molten rock)• Crust: thinnest layer of the earth made up of oceanic, which contains mafic minerals, and continental crust

Geologic Time Scale• The Earth’s history is divided into time divisions • Phanerozoic, Proterozoic and Archean are the largest time divisions measured in billions of years• Eras, Periods, and Epochs are the subdivisions of the large time divisions

• Layer of mantle above the asthenosphere• Not a continuous shell;

broken up into plate tectonics

• Convergent boundaries: Colliding• Subduction Zone: region

where “diving” takes place • Ex. Mariana Trench

• Divergent Plate: two plates move away from each other• Transform boundaries: Two

plates slide past each other

Lithosphere Plate Tectonics

GEOLOGICAL DISTURBANCES

Volcanoes•When magma reaches the Earth’s surface through cracks or vents in the crust• Composite Volcanoes: steep-sided, built of multiple layers of viscous lava and ash• Shield Volcanoes: Built almost entirely of highly fluid lava flow• Cinder Volcanoes: formed when lava is blown violently into the area and breaks into small fragments that solidify an fall as cinders• Lava Domes: formed when highly viscous lava is extruded from a vent and forms a rounded, steep-sided dome

Earthquakes • Occurs when built up strain in a rock mass causes a rupture.• Focus: region where rupture occurs• Epicenter: point directly above focus• Earthquakes are measured by a seismograph and classified by the Richter scale.• Earthquakes cause faults and tsunami, or a destructive tidal wave.

The Rock Cycle• Connection between the Earth’s internal and external processes.• Igneous rock most common rock type, formed when magma or lava cools• Sedimentary rocks formed by consolidation of weathered fragments or by lithification• Metamorphic rocks are formed when other rocks respond to elevated temperature

Soil Formation • Unconsolidated materials formed by weathering.• Transported by wind or water• Soil material tends to move vertically • Living component of the soil breaks down organic material• Climate, parent material, biologic organisms, topography, and time

Quiz

• What is planetesimals?• What is a subduction zone? • What are cinder volcanoes?• What can earthquakes

cause?• What is lithification?

• large clumps of solid material several kilometers in diameter• Region where “diving” takes

place• A volcano formed when lava

is blown violently into the area and breaks into small fragments that solidify an fall as cinders• Faults and tsunamis • Compaction

Questions Answers