I Why does Mars have so much iron on it's surface?

[rootone]

Earth also has iron rich deposits, I think generally they are thought to be remains of meteorites.
Same is likely for Mars, but there is a lot more iron (and compounds) on the surface of Mars than there is on Earth.
Are there substantial amounts of silicate rocks, as Earth has?

 

[BillTre]

Earth's most important iron ore deposits are found in sedimentary rocks. They formed from chemical reactions that combined iron and oxygen in marine and fresh waters. The two most important minerals in these deposits are iron oxides: hematite (Fe2O3) and magnetite (Fe3O4).

From: here.
Presumably the oxygen came from biological sources during the great oxygenation event.

 

[lomidrevo]

To your question from the title of this thread: Yes, the relative abundance of iron is higher on surface of Mars comparing to the Earth's surface. I think it is usually explained by the fact that Mars is a less massive planet than Earth and it was forming further from the Sun. Therefore it cooled more rapidly after the formation and the gravitational separation was not so significant as in case of Earth's evolution. That is why more iron exists in the upper layers of Mars, comparing to Earth.

 

[stefan r]

Earth's continents have been romping all around the globe. Denser materials sink. Lighter materials rise. Iron reacts with water and will make its way to the ocean floor. It is not raining on Mars there is no ocean and the surface is not broken up into continental plates.

 

[davenn]

Earth also has iron rich deposits, I think generally they are thought to be remains of meteorites.

that I would dispute unless you can find a really good reference

 

[rootone]

I don't have a specific reference, however it is I think established that Earth (and Mars) would have been heavily bombarded with meteorites for several millions of years after the planets initially formed, and a lot of meteors have a high iron content.

 

[jim mcnamara]

@rootone https://en.wikipedia.org/wiki/Late_Heavy_Bombardment

The LHB was an event that occurred after Earth's crust solidifed - large numbers of sizable asteroids collided with the inner 4 planets, and our moon.

 

[stefan r]

@rootone https://en.wikipedia.org/wiki/Late_Heavy_Bombardment

The LHB was an event that occurred after Earth's crust solidifed - large numbers of sizable asteroids collided with the inner 4 planets, and our moon.

There was solid crust but the current continental shelves and oceanic shelves formed much more recently.