Aeromagnetic surveys of Illinois, Indiana, and Ohio, merged to form seamless grids across the state. Gravity anomaly data are provided as well.
This data set includes a GIS geologic map database of an Early Proterozoic metavolcanic and metasedimentary terrane extensively intruded by Early and Middle Proterozoic granitic plutons. Laramide to Tertiary deformation and intrusion of felsic plutons ha
A digital magnetic anomaly database and map for the North American continent is the result of a joint effort by the Geological Survey of Canada (GSC), U. S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM). The database and ma
In 1986 and 1987, the U.S. Geological Survey (USGS), the Dirección General de Geología, Minas e Hidrocarburos, and the Universidad de Costa Rica conducted a mineral-resource assessment of the Republic of Costa Rica. The results were published as a large
An aeromagnetic map of the Death Valley groundwater model area was prepared from published aeromagnetic surveys as part of an interagency effort by the U.S. Geological Survey and the U.S. Department of Energy to help characterize the geology and hydrology
The grid files presented here are in ASCII format that uses the definitions of the grid exchange format (GXF). The files can be viewed using a suitable word processing program. The different grids are: >Kfrco.gxf potassium concentrations in the rocks
Gravity station data and hand-held magnetometer measurements with analysis and description of methodology.
Mathematical modeling and analysis of aeromagnetic anomaly data (gridded data provide in another report).
Hand-held magnetometer and sample magnetic susceptibility measurements used to help interpret complex patterns in the magnetic anomaly of this area.
Maps of aeromagnetic data and a table of gravity station data embedded in the PDF report, not as separate files
Gravity map and data used to infer details of the geologic structure of the area. Surveys were conducted during or prior to 1975.