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Currently most geologists favor the theory that earth formed via accretion from a protoplanetary cloud about 4.57 billion years ago.
The material that formed the terrestrial planets like Earth contained a concentration of short-lived radionuclides that was high enough that the radiation emitted by their decay heated the bodies up to their melting temperature. An additional source of energy for Earth is believed to be the so-called "giant impact", the collision of the proto-Earth with a roughly Mars-sized protoplanet in the early history of our planet. It is thought to have resulted in the complete melting of the upper 100s of km of the Earth.
In the its molten stage the Earth completed its differentiation (separation of elements that chemically are unsoluable within each other in large quantities) into a metal core and a silicate mantle.
As the Earth is loosing heat into space the inner part of the metal core started to crystallize and now forms the (I) solid inner core.
(II) The outer metal core is still liquid and is believed to play a key role in generating the Earth's magnetic field.
(III) The mantle is the shell around the core which is currently not very well understood in terms of its exact composition and rheological (the way that the material reacts on stresses leading to deformation) behaviour. Most geologists agree that the whole mantle or at least a portion of it convects and by this process the mantle in mixed and portions of the mantle ascend to rather shallow (i.e. close to the surface) levels and undergo partial melting. Formally the mantle can be subdivided into several zones depending on the stability of certain mineral phases and one often finds the subdivision into upper and lower mantle at a depth of about 660 km.
(IV) The melt extracted from the mantle forms most of the oceanic crust that we see today and is the first step to the creation of continental crust as well. The formation of continental crust is far more controversial than that of oceanic crust but involves melt extraction from the mantle and several remelting events of the basalts that crystallized from these melts. The continental crust as we know it today is buoyant, i.e. it "floats" on the mantle because of its lower density and builds stable land masses whereas the oceanic crust is continuously recycled and sinks into the mantle in subduction zones.
Wiki User
∙ 11y ago
Wiki User
∙ 9y agoThe earth was discovered as having 4 layers in 1909 after an earthquake. The scientist that discovered the four layers is unknown.
Wiki User
∙ 10y agoThe are;
1. Lithosphere - Solid.
2. Hydrosphere - Liquid.
3. Atmosphere - Gaseous.
4. Biosphere - Solid, Liquid and Gas.
Lynx
Idrk :B
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What are some questions a scientists would form about a sedimentary rock?
how old they are how long the layers formed what kind of rocks
Why do scientists believe that the earth developed in a series of layers?
because the earth as it builds up over time new layers formed from the techtonic plates each layer probobly has their own plates but not discovered yet and when convergent bounderies made mountains and more land, the earth made new layers that were capable of living on
Faults can form in which layer of the earth?
Faults are formed at the outer solid layers of the Earth. They are developed within the earths crust or Lithosphere.
How scientists believe the earths four layers were formed?
when this earth cooled from being hot, all the Iron and Nickle get concentrated inside earth forming inner two layers Inner solid core and outer liquid core. Then with the passage of time earth solidifies gradually and mantle solidifies and now at this stage our crust the outer most part of earth look like its final product.
How have scientist been able determine the composition of earths layers?
Scientists have been able to determine the composition of earth's layers using various ways. In most cases, samples have been taken and studied so as to determine the layers of the earth.
How do scientists believe the layers of the earth were formed?
dust and ice and other partcials
Which of earths layers is formed by volcanic activity?
Crust
What are facts on how the layers of the earth was formed?
No one knows for sure about how the layers formed. Scientists are trying to find out how. SORRY : (
How were earths layers formed as rocks melted?
They formed as heavier and lighter rocks separated
Which is a method scientists use to determine the composition of earths layers?
Shooting seismic waves into the planet
What made the Earths layers?
Your mom made the earths layers
How many layers in earths mantle?
there are 7 layers in earths mantle.
What is a method scientists use to determine the composition of earths layers?
Type your answer here... D.Comparing the composition of the crust to other bodies in the solar system
What are some questions a scientists would form about a sedimentary rock?
how old they are how long the layers formed what kind of rocks
Why do scientists believe that the earth developed in a series of layers?
because the earth as it builds up over time new layers formed from the techtonic plates each layer probobly has their own plates but not discovered yet and when convergent bounderies made mountains and more land, the earth made new layers that were capable of living on
Faults can form in which layer of the earth?
Faults are formed at the outer solid layers of the Earth. They are developed within the earths crust or Lithosphere.
How scientists believe the earths four layers were formed?
when this earth cooled from being hot, all the Iron and Nickle get concentrated inside earth forming inner two layers Inner solid core and outer liquid core. Then with the passage of time earth solidifies gradually and mantle solidifies and now at this stage our crust the outer most part of earth look like its final product.
