Explore Iowa’s early geology with a detailed 1893 report that maps, explains, and inventories the state’s rocks and resources.
This edition compiles field notes, sections, and illustrative plates from the Iowa Geological Survey’s Second Annual Report, offering a window into how geologists in the 19th century studied coal measures, lime- and gypsum-bearing formations, and the drift-dominated landscapes of eastern and western Iowa.
The volume presents scope and methods, describes key formations such as Saint Louis Limestone, Lower Coal Measures, and gypsum deposits, and discusses topography, drift, and regional controls on mineral resources. It combines administrative context with substantive geologic observations, including maps and cross-sections that researchers and enthusiasts can use to understand Iowa’s early resource geology.
- Geographic and stratigraphic setup: where major formations lie and how they relate to coal, gypsum, and stone deposits.
- Maps and cross sections: visual tools showing the Des Moines River region, gypsum area, and coal-bearing zones.
- Descriptions of formations: Saint Louis Limestone, Lower Coal Measures, gypsum beds, drift and glacial influences.
- Topography and field notes: how terrain shapes accessibility and resource potential, plus notes on ancient channels and driftless areas.
Ideal for readers of local history and geology who want historical context for Iowa’s mineral resources and early survey work.