Scanning Earth's Subsurface for Groundwater
USGS scientists use heliborne electromagnetic (HEM) survey to scan the Earth's subsurface in search of groundwater. Transcript available soon....

The Mississippi embayment — a look underground
Water, oil, and gas wells (shown as green lines) are drilled to hundreds or thousands of feet below land surface in an area known as the Mississippi embayment. Information gathered from these wells was used to create a 3D computer model of underground formations. Many of these formations (shown as s...