SUBSURFACE MAPPING AT SOCIETALLY RELEVANT SCALES: AIRBORNE ELECTROMAGNETIC IMAGING

There is a critical and growing need for information about subsurface geological properties and processes over sufficiently large areas that can inform key societal studies. Airborne geophysical methods fill a unique role in Earth observation because of their ability to detect deep subsurface properties at regional scales and with high spatial resolution that cannot be achieved with ground-based measurements. Airborne electromagnetics, or AEM, is a technique that is rapidly emerging as a foundational tool for geological mapping, with widespread application to studies of mineral and water resources, geologic hazards, infrastructure, the cryosphere, and the environment. Applications of AEM are growing worldwide, with rapid developments in instrumentation and data analysis software within just the past ten years.

Much like satellite and other airborne remote sensing methods have transformed our view of Earth’s surface, AEM and other airborne geophysical methods have the potential to extend our views into the subsurface. I will provide some background on the AEM method and its application to date across a range of disciplines. Looking ahead, a more systematic initiative is needed for national-scale acquisition of AEM data as a baseline geoscientific dataset in support geologic mapping and related applications.