Magma is the molten rock below the crust, in the mantle. Tremendous heat and pressure within the earth cause the hot magma to flow
in convection currents
. These currents cause the movement of the tectonic plates that make up the earth’s crust.
What is magma how does it move tectonic plates?
A small amount of molten rock located under tectonic plates encourages them to move
. It is subdivided into rigid plates, known as tectonic or lithospheric plates. … These move on a more fluid layer of the mantle, the asthenosphere
What are 3 ways that continental plates can move?
The movement of the plates creates three types of tectonic boundaries:
convergent, where plates move into one another
; divergent, where plates move apart; and transform, where plates move sideways in relation to each other.
What happens to magma as it moves through continental crust?
Once the molten mantle rock forces its way through the crust,
it eventually erupts through the volcano as lava
. This lava cools and forms rocks that scientists study to try and tell them more about what is happening to cause volcanic eruptions and how the mantle is stored under a volcanic area.
What force moves continental plates?
Lithospheric plates are part of a planetary scale thermal convection system. The energy source for plate tectonics is Earth’s internal heat while the forces moving the plates are the
“ridge push” and “slab pull” gravity forces
.
What drives the plate to move?
The heat from radioactive processes within the planet’s interior
causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.
What happens when two continental plates collide?
Plates Collide When two plates carrying continents collide, the continental crust buckles and rocks pile up,
creating towering mountain ranges
. … Plates Slide Past One Another Plates grinding past each other in opposite directions create faults called transform faults.
What is the force of magma beneath to move?
A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces
buoyant forces
on the magma that tend to drive it upwards.
What are the 3 types of magma?
It also contains small amounts of dissolved gases such as water vapor, carbon dioxide, and sulfur. The high temperatures and pressure under Earth’s crust keep magma in its fluid state. There are three basic types of magma:
basaltic, andesitic, and rhyolitic
, each of which has a different mineral composition.
Why is rhyolitic magma explosive?
Explosive eruptions are favored by high gas content & high viscosity magmas (andesitic to rhyolitic magmas). The explosive bursting
of bubbles fragments the magma into clots of liquid that cool as they fall through the air
.
What are 2 pieces of evidence for continental drift?
The evidence for continental drift included
the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones
.
Why do oceanic plates dive underneath continental plates when they collide?
When an oceanic plate converges with a continental plate, the oceanic crust will always subduct under the continental crust; this is because
oceanic crust is naturally denser
. … Old, dense crust tends to be subducted back into the earth.
How fast do plates move?
They can move at
rates of up to four inches (10 centimeters) per year
, but most move much slower than that. Different parts of a plate move at different speeds. The plates move in different directions, colliding, moving away from, and sliding past one another. Most plates are made of both oceanic and continental crust.
What drives the plates to move draw a cross section of the earth?
Plates at our planet’s surface move because of
the intense heat in the Earth’s core that causes molten rock in the mantle layer to move
. It moves in a pattern called a convection cell that forms when warm material rises, cools, and eventually sink down.
What makes the two plate move away from each other?
A divergent boundary
occurs when two tectonic plates move away from each other. Along these boundaries, earthquakes are common and magma (molten rock) rises from the Earth’s mantle to the surface, solidifying to create new oceanic crust. … Two plates sliding past each other forms a transform plate boundary.
What makes lithospheric plates move?
The heat from the mantle makes the rocks at the bottom of lithosphere slightly soft
. This causes the plates to move. The movement of these plates is known as plate tectonics.
