Iowa Code § 456.3
The state geologist shall be director of the survey and shall make a complete survey of the natural resources of the state in all their economic and scientific aspects, including the determination of the order, arrangement, dip, and comparative magnitude of the various formations; the discovery and examination of all useful deposits, including their richness in mineral contents and their fossils; and the investigation of the position, formation, and arrangement of the different ores, coals, clays, building stones, glass sands, marls, peats, mineral oils, natural gases, mineral and artesian waters, and such other minerals or other materials as may be useful, with particular regard to the value thereof for commercial purposes and their accessibility.
Iowa Code § 456.3
2002 Acts, 2nd Ex, ch 1003, §260, 262