Select Airborne Techniques for Mapping and Problem Solving

Airborne techniques have been widely used to map geologic structure and measure tectonic deformation across California. The suite of techniques discussed here can be used alone or in combination to obtain more accurate and detailed information about areas that are dif cult to observe on the ground. Airborne gravity and magnetics use small variations in the Earth’s gravitational and magnetic eld to map geologic structure. LiDAR (Light Detection and Ranging) uses lasers to produce high-resolution topography that can be used to map ne-scale tectonic landforms such as fault scarps. Structure from Motion (SfM) uses cameras to collect images from different perspectives to produce 3D models of a target, providing details of the topography. Unmanned Aerial Vehicle Synthetic Aperture Radar (UAVSAR) uses radar to measure motion of the Earth’s crust by combining two images separated in time, but collected from exact repeat passes. It is proving useful for measuring co-seismic displacements and slip on faults, as well as for detecting ground movement caused by landsliding. An advantage of airborne geophysical techniques is that ight paths are easily adapted to speci c situations, and areas that may be dif cult to observe on the ground can be surveyed remotely by air.