Helicopter magnetic and gravity gradiometry survey over the Pea Ridge iron mine and surrounding area, southeast Missouri, 2014

High resolution magnetic and gravity gradient data were collected using the HeliFalcon airborne gravity gradiometry system together with a stinger-mounted magnetometer. The survey took place out of the Sullivan, Missouri airport during March of 2014. The survey covers a 35 x 37 square-kilometer area centered on the Pea Ridge iron oxide-apatite rare-earth element deposit, which is located about halfway between the towns of Sullivan and Potosi, Missouri. Data were collected along north-south flight lines spaced 400 m apart with east-west tie lines flown every 4000 m. A nominal flight height above terrain of 80 m was maintained except where safety dictated a higher elevation. A total of 3538 line km of data were collected. Three files are available in this publication and include flight line data for the magnetic survey, flight line data for the gravity gradiometry survey and a report describing the survey parameters, field operations, quality control and data reduction procedures.