Plate Tectonics and Earth Structure

Flashcards about plate tectonics, natural hazards, and Earth's structure.

What is a natural hazard?

A natural event that threatens people or has the potential to cause damage, destruction, and death.

Name three geological hazards.

Earthquakes, volcanic eruptions, and tsunamis.

Name three climatic hazards.

Cyclones, droughts, and floods.

What are the three major components of the Earth's structure?

Crust, mantle, and core.

What are the two types of crust?

Oceanic crust and continental crust.

What are the characteristics of oceanic crust?

It lies beneath the oceans, is thinner and denser, and is younger.

What are the characteristics of continental crust?

It makes up the land, is thicker and less dense, and is older.

How does oceanic crust compare to continental crust in terms of renewal?

Oceanic crust is continually renewed and destroyed, while continental crust is not easily destroyed.

What is the geology of Oceanic crust?

Mainly basalt, silica, and Magnesium (SiMa).

What is the geology of Continental crust?

Range of granites, silica, and Aluminum (SiAl).

What is the mantle?

The thickest part of the Earth, made of hot, semi-molten rock (magma).

What are the two regions of the mantle?

Upper mantle and lower mantle.

What is the outer core made of?

Hot liquid iron with some nickel.

What is the inner core made of?

Solid sphere iron with some nickel.

What makes up the lithosphere?

The crust and the uppermost solid mantle.

What is the asthenosphere?

A hot, smooth, semi-liquid zone in the upper mantle.

How many tectonic plates are there?

Seven giant pieces and at least 12 smaller ones.

Name the 7 major tectonic plates.

North American, South American, Eurasian, African, Indo-Australian, Pacific, and Antarctic plates.

What causes convection currents in the mantle?

The extreme heat from the core.

What are the three main types of plate movements/margins?

Destructive, constructive, and transform.

What is a destructive/convergent plate margin?

An oceanic plate and a continental plate moving towards one another, causing subduction and earthquakes.

Give an example of destructive margins

Pacific Plate and Eurasian Plate / Nazca Plate and the South American Plate.

What is a constructive/divergent plate margin?

Plates move apart, magma rises, and new land forms.

Give examples of constructive margins

South American Plate and African Plate / Eurasian Plate and the North American Plate

What is a transform/conservative plate margin?

Plates move past each other, causing friction and earthquakes.

Give an example of a transform margin?

The San Andreas Fault in California.

What are the processes involved with a divergent plate boundary and its characteristics?

Sea-floor spreading, rift valleys, earthquakes, volcanic activity.

What are the processes involved with a convergent plate boundary and its characteristics?

Earthquakes, Volcanic Activity. Deep sea trenches Volcano along coast of continent, High continental mountain chains.

What are the processes involved with a transform plate boundary and its characteristics?

Earthquake activity

Give examples of a divergent Boundary

Mid-Atlantic Ridge, East Pacific Rise

Give examples of a convergent Boundary

Islands of Indonesia, Mariana Islands, West coast of S. America, Himalayas

Give examples of a transform Boundary

San Andreas Fault, North Anatolian Fault, Fracture zones along mid-ocean ridge