The restless earth Flashcards
Name all 4 layers of the earth’s structure?
-The inner core (hot, solid centre)
-The outer core (liquid layer surrounding the inner core)
-The mantle (Thick layers of magma)
-The crust (thin layer of solid rock making up the outer shell of the Earth.
What are the names of the two plates?
-oceanic
-continental
How is the crust formed?
By magma from the mantle rising and cooling.
What are the two names of the parts of the mantle?
-Lithosphere (brittle)
-Asthenosphere (malleable)
What are convection currents?
The magma in the mantle rises and reaches there cooler part the lithosphere then cools and sinks down. This happens repetitively and in a circular motion causing lateral pressure and moving the tectonic plates.
Movement
Constructive- outwards
destructive- inwards
conservative- side by side
collision- inwards (two continental)
What is a tectonic plate?
A tectonic plate is a slab of solid rock, composed of both continental and oceanic crust.
What are earthquakes?
Earthquakes are vibrations caused by earth movements at plate margins or major fault lines.
What is a fault?
A fault is a fracture in the rocks that make up the earths crust.
What is the focus?
The point within the earth where an earthquake rupture starts.
Epicentre?
Directly above the focus.
Seismic waves?
Waves that transmit the energy released by an earthquake.
What are seismic waves measured with?
Seismic waves are measured using seismometer. A seismometer records the power of the waves.
What is a volcano?
A volcano is an opening in the earth that lava, ash and gases can escape.
