In earth Crust the element Iron is abundant, I like to know how the Earth has accumulated this element.
That's very interesting post , Dr Ghosh. Iron by weight constitutes 5% and by mass,
iron constitutes nearly 35% of was the crust. It's abundance in earth crust is linked to irons ability supernova nucleosynthesis and ability to absorb much less stellar energy...
The core of the earth is iron. This is from material of that originally formed the earth millions of year ago. Developed the strength of our gravitational field
Most material in our universe comes or are derived from stars. Within stars all lighter material will be subject to fusion, releasing energy and creating heavier and heavier materials. This will happen all the way until iron, since iron can't really fuse into heavier materials. This is one side of the spectrum.
Most materials can also fuse by chance, with cores fusing and creating a lot heavier materials than iron. Many of these though are subject to fission since they are radioactive, when these materials undergo fission, they will become lighter. The heavier material, the more likely it is to undergo fission. This will happen all the way until Iron, since iron can't undergo fission. This is the other side of the spectrum.
Since Iron is met on both sides of the spectrum, iron is the end stage of many material in our universe. If a lot of material in the universe is iron, it makes sense that our planet also constitutes a lot of iron. Also notice that Earth is quite close to the sun, and will contain more iron than planets further out in our solar system.
Earth and other planets formed from suns supernova which rich in iron
Dr Carl Alexander Frisk has explained in a very simple and attractive way for the creation of different elements through nuclear fusion reaction. It also appears to me that explosion of sun might have taken place to form this earth after the production of this heavy metal the iron through fusion reaction. This could probably be the reason for the abundance of iron on earth. Thank you sir.
In addition to what Carl Alexander Frisk has so eloquently and lucidly stated I would like to add something more in tune to the question regarding the easy availability of copious amount of iron in the crust of planet Earth.
Our solar system was assembled, as far as we presently know, from the aftermath of a pre-existing supernova. The aftermath was in the form of interstellar debris that coalesced and conglomerated under their gravity pull to form the G2V yellow dwarf star we know as the Sun along with its associated planets and planetoids which again reshuffled and coagulated with each other to finally settle as our present solar system. In that centrifusion of astronomical proportion the heavier elements (physics of nucleosynthesis has already been stated by Carl Alexander Frisk), mainly Nickel to Iron via Cobalt, settled deeper within each nascent bolas of molten material and the lighter ones remained on top.
Our primordial Earth was constantly being bombarded by projectiles of ice, metals, crystals which had all formed and settled within the juvenile solar cloud or produced through inter planetary collisions, due to the lack of a protective screen we call the 'atmosphere'. The constant collision of meteorites as well as encroachment of ferruginous plumes from below the surface enriched the young earth's molten surface with iron. The meteorites brought in lot of ice crystals and that provided the moisture in addition to steam generated from within Earth and this condensed gradually to form our first non-saline ocean which helped to cool down the crustal layers rapidly due to liquid water's specific heat capacity.
Thus, initially our planet had two separate reserves of iron, the very lower concentrations at the crust and almost the entirety at the core as Ni-Fe alloy.
BUT, the oceanic waters dissolved much of the crustal iron and it remained that way for a very long time until biological processes started sequestering iron in their systems and with the liberation of oxygen through water splitting by autotrophs, iron oxides (banded iron formation event) staretd to precipitate and again enriched the crust of Earth as quarriable ores we utilise today.
Hence, although nuclear fusion and fission might have given rise to iron as element but the availability of iron in the crust is to the largest extent attributed to the biological processes. And it will not be prudent to state the abundance of only iron in the crust since Aluminium as a metal is far more abundant compared to iron within the crust.
I most sincerely believe that my explanation has shed some light on the fantastic discussion initiated by Dr. Phanibhusan Ghosh.
With regards,
Dr. Abhishek Mukherjee