Surveys originally carried out by Soviet geophysicists from 1972 through 1974 were digitized. Georeferencing was problematic as were some of the measured characteristics; we explain what we did and how we have understood these data.
Geophysical interpretation of the southern EspaƱola basin for the purpose of understanding the hydrogeologic framework including shallow faults, igneous units, and basement rocks
Survey to map concealed faults that may be related to geothermal resources, such as hot springs; data given are surface locations of faults interpreted from the survey.
Explanation of the Earth's magnetic field and how USGS measures it. Defines magnetic anomaly, induced and remanent magnetism in rocks, and describes magnetic anomaly maps.
Database includes new helicopter aeromagnetic data, point locations of the local maximum horizontal gradient derived from the aeromagnetic data, and physical property data.