Volcanoes Flashcards
What are three types of volcanoes?
Dormant, active, extinct
One eg. Of active volcano?
Mount etna, Italy.
One eg. Of dormant volcano?
Mount st. Helens
Info on mt st. Helens?
Erupted in 1985 after 120 yrs
What happens when plates move?
Volcanoes, and fold mountains form and earthquakes occur.
How can plates move?
The plates can move together apart or side-by-side.
Define destructive plate boundary.
Where two plates collide. have your plate sinks under the lighter plate and goes into the mantle in the mantle the heavier plate melts. Blobs of magma can rise up through the plates to produce volcanoes. As the two plates the edge of the lighter plate crumbles and fold mountains earthquakes also occur at destructive boundaries. (this is a vital topic as it is related to fold mountains, volcanoes, earthquakes, and earth.)
The crust of the Earth is broken into what two types of plates?
Continental plate and oceanic plates.
What are the three types of plate boundaries?
Constructive destructive, conservative plate boundaries.
Define constructive plate boundaries.
Constructive plate boundaries our two plate separate as the plates move apart magma can rise up through a fault or crack in the crust. The magma cools rapidly and adds (constructs) New rock to the crust. Volcanoes/volcanic islands form at constructive plate boundaries.
Define conservative plate boundaries
Where plates move side-by-side no crust is formed or destroyed at these boundaries. Earthquakes often occur here to play to Moving side-by-side can get stuck, when they slip forward suddenly this causes an earthquake.
Define convection currents.
Convection currents are large currents of hot magma that move in the mantle. Convection currents in the mantle move the earths plates. The earths crust is broken into plates convection currents in the mantle caused the plates move, when the plates move the continents drift.
What are the edges of the continental plates and oceanic plates called?
Plate boundaries
When did earth form?
Earth formed around 4.54 billion years ago
Define plate tectonics
Play tectonics is the idea the earths crust is broken into plates. These plates are moved by confection currents.
Who studied plate tectonics?
A German scientist named Alfred Wegener studied this in 1912
The continents were all part of a supercontinent called what 200 million years ago?
Pangaea
In the 1960s earth scientist discovered what?
Continental drift. Definition= places under the ocean where the plates separated or spread away from each other.
By how many years ago did the continents reach their present day locations?
65 million years ago
What did Alfred wegener call when the continents reach their present day locations?
Sea floor spreading
What are the three cores?
Inner core, outer core, and core
What are the three parts of the Earth called?
Crust, mantle and core
What is the crust made out of?
Solid rock
How thick is the crust under the oceans?
Between 30 and 100 km thick under the oceans.
What does the crust float on?
The mantle
The crust is broken into pieces called?
Tectonic plates
What is under the crust?
Mantle
How high can the temperature reach in the mantle?
Up to 4000°C
Most of the mantle is solid except for a zone underneath the?
Crust
There is semi molten rock called ____
Magma. (Magma moves in currents called convection currents.)
What is in the centre of the Earth?
Core
What is the core of the Earth made of?
Nickel and iron
What is the temperature of the core?
5000°C
Decor is divided into two parts what are they called?
Inner core and outer core
Is the inner core solid or liquid?
The inner core is solid due to pressure
Is the outer core solid or liquid?
The outer core is molten
The convection currents go in what motion?
A circular motion
What is molten?
Melted rock
What is magma?
Semi molten rock
What is a mid ocean Ridge?
A ridge of underwater mountains formed where two plates separate and magma solidifies underneath the ocean eg. the mid Atlantic Ridge.
What does the word mount etna mean? What language is it translated from? How tall is it? Is it active dormant or extinct?
The word mount etna means I Burn in Greek. it is 3330 meters high it erupts regularly meaning it is active.
What is an example of an extinct volcano?
Slemish, County Antrim
What does distribution describe?
Distribution describes where something is example distribution of volcanoes mean where volcanoes are
Volcanoes occur where?
Volcanoes occur at destructive and constructive plate boundaries (volcanoes form where two plates collide)
What is the pacific Ring of fire?
The Pacific Ring of fire is a zone of active volcanoes and earthquake that line around the edge of the Pacific Ocean eg. Mount Fuji.
Define extinct.
Has not erupted in historic times.
Define dormant.
Has not erupted in awhile
Define active
Regularly erupting.
