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Integration of Geophysical Data with The National Map Data

The geophysical data integration project at CEGIS currently involves leveraging large web-based data sets with local surveys and The National Map in order to extend the range and the resolution of such surveys with a minimum expenditure on additional field time.  Most recently this has been applied to the North American Gravity Database.


Combining data from a local field survey (red dots) with statistically compatible data from the North American Gravity Data base (blue dots) yields a data set with much higher resolution and areal extent than either data set on its own.



Elevation Difference and Bouguer Anomaly Analysis Tool (EDBAAT) integrates gravity data for a chosen geographic area in CONUS with The National Map elevation layer.

EDBAAT will:

  • Query area of interest
  • Extract best resolution DEM from TNM covering entire area
  • Extract Gravity data from gravity database.
  • Interpolate DEM elevations for each gravity point and compare and flag the difference in elevation.
  • Compares gravity values with nearest neighbors and flags those which fall outside a 95% confidence interval.
  • Generates a report listing all flagged points to allow user to choose most reliable points for reconnaissance studies or survey enhancement data.

Download EDBAAT here

Download EDBAAT Installation Guide here

Download EDBAAT Developer/User Guide here


Paleomagnetic Data

Paleomagnetic data for the United States was extracted from the Global Paleomagnetic Database as released by the National Geophysical Data Center (NGDC) of the National Oceanic and Atmospheric Administration (NOAA) was originally compiled but the International Association of Geomagnetism and Aeronomy (IAGA).


In this study:

  • Paleomagnetic data are geospatially integrated with TNM layers and archived geologic map data in the county of Ste. Genevieve, Missouri.
  • Paleomagnetic data are not very sensitive to the geospatial location of the sample as compared with the geologic formation from which they were sampled. Therefore integration is achieved  via formation occurrence rather than geospatial coordinates.