Airborne electromagnetic and magnetic survey of Delaware Bay and surrounding regions of New Jersey and Delaware, 2022 (ver 2.0, April 2025)

Airborne electromagnetic (AEM) and magnetic survey data were collected during July and August 2022 over a distance of 3,588.5 line kilometers covering Delaware Bay and surrounding regions in New Jersey and Delaware. Data were collected as part of the USGS Delaware River Basin Next Generation Water Observing Systems (NGWOS) project to improve understanding of groundwater salinity distributions near Delaware Bay. The survey was primarily funded by the USGS, with partial support through collaboration with the University of Delaware to extend data collection to parts of Rehoboth Bay and Indian River Bay. Data were acquired by SkyTEM Canada Inc. with the SkyTEM 304M time-domain helicopter-borne electromagnetic system together with a Geometrics G822A cesium vapor magnetometer. The survey was acquired at a nominal flight height of 30 - 40 m above terrain along parallel flight lines primarily oriented southwest-northeast and with nominal line spacing of 500 m over land and nearshore, and 3000 m over open-water parts of Delaware Bay. Several irregular flightlines were acquired along, and perpendicular to, nearby rivers to capture salinity patterns along these hydrologic flowpaths. Version 2.0 includes additional processed AEM data and inverted resistivity models.