The timeline for In Situ Resources Utilization (ISRU) depends on the type of colonization and missions.
The favored type of mission at this time, by SpaceX (Mars One), NASA(ISP ver.5) and the Mars Society(Mars Direct) all rely on ISRU to produce part of the products needed for their operation and success.
The resources and productions planned are listed in the following table by order of development:
|Regolith||Water||Water, CH4, O2 and H2, food*.|
|Atmosphere||CO2||Propellant, Carbon, Oxygen, food.|
|Atmosphere||Nitrogen||Settlement air, cold thruster gas, food.|
|Regolith||Regolith||Radiation shielding, roads.|
|Regolith||To be determined**||Cement, Marscrete, Compressed Regolith Blocks.|
|Regolith||Iron Oxyde Fe2O3||Iron, steel|
|Regolith||SiO2, Sodium Carbonate||Glass|
|Basalt||Rock||Construction stone, roads|
|Clay||Very fine separated ores||Ceramics|
|Salt deposits||Sodium chloride||Salt|
*Although food will be produced rapidly for experimental and morale purposes, large scale production will probably wait for the colony population to grow substantially before it becomes economical.
**The best construction material made from regolith will be the subject of some of the first materials research done on Mars and an important scientific objective of initial missions.