Skip to main content
U.S. flag

An official website of the United States government

This site is currently in beta, and your feedback is helping shape its ongoing development.

Borehole Electromagnetic Induction, Natural Gamma, and Nuclear Magnetic Resonance Logging in the Cedar River Floodplain, Cedar Rapids, Iowa, 2017

Published by U.S. Geological Survey | Department of the Interior | Metadata Last Checked: January 27, 2026 | Last Modified: 2020-08-13T00:00:00Z
In June 2017, the U.S. Geological Survey (USGS)collected borehole geophysical logs to characterize the shallow alluvial aquifer in and near Cedar Rapids, Iowa. Borehole geophysical logs were collected in nine shallow boreholes to identify geophysical properties of the aquifer in the area surrounding the boreholes. Electromagnetic induction logs were used to determine the electrical properties of the fluid and formation surrounding the borehole. A natural gamma tool was used to identify the naturally occurring gamma radiation that is emitted from the earth materials. Nuclear magnetic resonance (NMR) tools were used to measure the water content and estimate the pore-size distribution and hydraulic conductivity (K) for each measurement interval in the saturated zone. Estimates of K were determined using two commonly used empirical relations. These estimates of K are order-of- estimates of K and can be used as relative estimates of K. Collectively, these borehole geophysical logs can be related to the stratigraphic layers of sand, gravel and fine sand in the aquifer.

data.gov

An official website of the GSA's Technology Transformation Services

Looking for U.S. government information and services?
Visit USA.gov