100k geological maps are considered as basic geological maps. Engineering maps also are prepared in some hazardous regions. The maps have explanatory report which printed adjacent or back of the paper map. Each 100k map contains 2500 square kilometers of country, 0.5 degree in length both longitudinally and latitudinally. Iran consists of about 660 100k sheets. About 90% of 100k geological mapping of country has been done. Remained areas mainly include desert zones.

   Systematic geochemical studies help to discover mineral potentials for further exploration. Before great Islamic Revolution of Iran, just foreign companies were performing geochemical studies. Until 1997, these studies were limited to only one 100k sheet per year. By progressive works, the number of studied sheets rose up to 39 sheets per year in 2003. Also this procedure led to huge improvement of private sector. So far nearly 50% of overall country has been studies.

   Theses maps are the result of gis compilation of information layers (geology, remote sensing, airborne geophysics, geochemistry, economic geology), which are derived from regional exploration. GSI starts to use this method in 1999. During Third Development Plan of country, 20 zones were selected to explore in this way.

   Mostly geochemical, geophysical and so on maps prepared in prospecting or explorational projects.

   Until Third Development Plan, virtually no part of 2500km of country's coastlines was studied. So coastal engineering and mineral potential assessment of southern and northern seawaters of country planed by GSI to study heavy elements distribution, environmental impacts, salinity, marine currents, sediments, bathymetry and .