Geophysical Remote Sensing Techniques

The Notre Dame Archaeology Field School is one of the few archaeology field schools to introduce students to geophysical survey techniqes.


Magnetometry (Gradiometry)

Students conduct magnetic surveys with a Geoscan FM36 Fluxgate Gradiometer. The data from this highly automated instrument is used to make a magnetic map of the Old College site (a historic archaeological site on the Notre Dame campus).

 
The magnetic data are processed with simple computer programs and the assistance of a student-friendly instructor to produce maps of the magnetic fields at the site. The magnetic data is downloaded to a portable computer where it can be processed and evaluated on-site.

 
 
 
 
 
 

A contour map of magnetic data from the Old College site shows a large magnetic anomaly in the southeast corner and scattered anomalies to the north characteristic of buried iron.
 
 

Excavations show that the large negative magnetic anomaly is the foundation of a 19th century farmhouse.

  Extensive gradiometer surveys were conducted over a four year period at the Bennac Village.  


The map below shows magnetic data from the Bennac Village site.  You can easily see a modern septic tank and tile field in the upper right corner (don't want to dig there!).  Archaeological features are indicated by letters.  They include scattered historic artifacts and a prehistoric fire place ("C").

The magnetic map was produced with TNT-Lite, an image processessing program from MicroImages, Inc. using computers in one of the DeBartolo Collaborative Classrooms.  


Resistance Survey

A Geoscan RM15 resistance meter is used to take resistance readings at 1 meter intervals across portions of an archaeological site.

The resistance data from the Bellinger site show two looter's pits (potholes) in a mound at the site.
The resistivity data color maps were made using an evaluation copy of Geoplot (version 2) supplied by Geoscan Research, Ltd and Dr. Lewis Sommers.

The map below shows resistivity data from the Bennac Village site.  Compare these results with the magnetic data shown above.  The complementary nature of magnetic and resistivity data are clearly visible.

The magnetic map was produced with TNT-Lite, an image processessing program from MicroImages, Inc.




You can also see the results of geophysical surveys during earlier field schools at:

Go to the Field School Home Page

Visit the Summer Session Page

Go to the Anthropology Department Home Page

Go to the Notre Dame Home Page

Learn about the NDDown program for downloading geophysical data (and obtain a copy)