Geological Records Unit

The Geological Records Unit will be closed to outside visitors as a precaution due to the COVID-19 pandemic until further notice, effective immediately.  

Updated:  9:31 pm CDT, Monday, March 16, 2020.

The Geological Records Unit (GRU) is the state repository for drilling records as mandated by statute. The collections include records for more than 500,000 oil and gas wells, water wells, engineering borings, and miscellaneous test holes drilled in Illinois. Many regions of the state lack abundant outcrops and road and stream cuts due to relatively flat topography. Drill hole records provide the most abundant data available for geologic interpretation. These data are useful for environmental assessment, mineral resource evaluation and groundwater resource evaluation and protection. GRU is the gateway to Illinois geology.

Since all records are filed by location - county then section, township, and range, please have this information ready when requesting information by phone or email. Some sources for legal descriptions are tax records, property titles and mortgage records, and plat books.

Hours: Monday - Friday, 8:00 a.m.- 4:30 p.m.
Mailing address:
      Geological Records Unit
      Illinois State Geological Survey
      615 East Peabody Drive, Room 239
      Champaign, IL 61820
Phone: 217-333-5109
Fax: 217-244-4544