Geophysical Investigations
In the late 2010s, archaeologists used geophysical survey techniques at Singer to locate and map Native village locations and any potential house basins within each stain.
Geophysical survey uses a varity of techniques to identify and map the physical, magnetic, electrical, and chemical properties of soil at a site, like trash pits and middens, walls, and houses. These techniques measure electrical current conduction, magnetisim, electromagnetisim, or sound waves. Because many natural and human activities can impact soils, geophysical researchers use multiple survey techniques to get the most complete picture of a site's below-ground deposits.
Magnetic gradiometry was one technique archaeologists used at Singer. This technique works in ways similar to a metal detector. The instrument - a magnetometer- measures the below-surface magnetic signature and magnetic intensity of metals like iron, nickel, and cobalt. Soils in midden stains, houses, and trash pits will have different values of magnetic intensity than surrounding soils. These areas showed up on the Singer maps as darker areas.
The most productive technique used at Singer was electromagnetic induction.Electromagnetic induction instruments measure the electrical conductivity (electro-) and the magnetic suseptibility (-magnetic) of soils. They do this by creating an electromagnetic field around the instrument, which then sends electrical currents into the soil. The instrument then measures the soil's electrical and magnetic properties. At Singer, heightened electrical and magnetic soil properties corresponded to midden stains - areas where Native people had built houses, threw out trash, and buried their dead. On the Singer maps, these midden stains showed up as dark red areas.
Prior to the geophysical survey, archaeologists had documented four midden stains at Singer using traditional archaeological survey techniques. Geophysical survey helped researchers confirm two additional midden stains, and they suspect that a third may be present. This brings the total number of midden stains - and circular villages - at Singer to seven. This discovery makes Singer unique for Kentucky and indeed for the entire Fort Ancient region.