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All News and Pages Related to "cave"

Allamakee County, Iowa

Posted on June 19th, 2015

KARST TERRAIN Karst terrains form by the dissolving of limestone or dolomite by groundwater. Typical features of karst terrains are caves, sinkholes, and springs. Many sinkholes have developed in the Galena Group in Allamakee County. Ludlow Township contains the most sinkholes in the state, with over 3,000 sinkhole identified.

Paleokarsts in Iowa

Posted on March 24th, 2015

Paleokarsts in Iowa by Robert M. McKay Following heavy rain, a muddy torrent of water laden with dislodged soil, twigs and leaves rushes down a gully and spills over a lip of rock, disappearing into a dark echoing hole. Crashing to the bottom of the pit, the flow continues outward and downward along narrow passageways […]

History: 1947–90

Posted on May 13th, 2014

In 1947, H. Garland Hershey succeeded Trowbridge, with whom he had served as assistant state geologist beginning in 1939. This was also the watershed year in which the director of the Geological Survey and the chair of the Department of Geology were separated into two full-time positions. Today the Geological Survey and the Department of […]

General Geology

Posted on April 30th, 2014

Mineral, Rock, and Fossil Identification Geologists at the Iowa Geological Survey regularly identify rocks, minerals, and fossils that are brought into our office.  If you are not able to stop by our office, send photos of the specimen via email.  Please make sure that the photos capture all aspects of the specimen, are in focus, […]