One way to limit iron corrosion is to coat the iron with a metal that:
will never undergo corrosion
reduces more easily than iron and will reduce the overall amount of oxidizing agents in the area
oxidizes more easily than iron and could provide a protective coating over the iron
absorbs water and keeps the iron dry

  1.)One way to limit iron corrosion is to coat the iron with a metal that: 
A.)will never undergo corrosion 

Large asteroid and comet impacts. because they can have a huge impact on the environment, such as a loss of land, and crust on the earth with the big holes they produce. on the other hand, volcanic eruptions can also cause change within the environment by producing land, but im actually not quite sure which one would be a better answer, hopefully you read this and didnt just flat out choose the first sentence i have spoken! your welcome~