Why Save Earthworks?

Why Save Earthworks?

Even in their degraded condition, ancient monuments are still priceless cultural and scientific resources. Fortunately, the Hopewell builders dug down well below the topsoil before beginning the construction of their monuments. Thanks to modern archaeological technology, the foundations of these national treasures can still be detected, without even excavating. Dr. Jarrod Burks uses the following technologies to map the locations of earthworks, even when they are invisible above ground:

Jarrod w Magnetometer

Magnetometers are good for detecting burned earth and concentrations of organic-rich soil, like middens or cooking pits.

Fire was a big part of the ritualized construction methods used by the Hopewell and other mound-building cultures. Fires were often built on the bare subsoil surfaces that were exposed before construction began. Also, when Native Americans gathered at these sites for ceremonies, many fires, cooking pits and middens were created outside the walls of the ceremonial area. Magnetometers can help make discoveries about how and when these monuments were used by their builders and the people who participated in ceremonies there.

Jarrod w Resistivity MeterElectrical Resistance Meters are good for detecting compacted surfaces, sand layers, gravel layers or any layer that contrasts with the surrounding soil.

The best instrument for mapping the locations of former walls and mounds, electrical resistance meters have provided much exciting information about the shapes and sizes of these ancient monuments. Mounds and walls were built carefully by the Hopewell so that they would endure. Often times, layers of different materials were used, one over another. The foundations of an embankment might be dark clay, but an iron-rich red clay might be used to cap the wall. Mounds often had alternating layers of sand and clay, then a cap of gravel or cobbles.

Jarrod w GP Radar

Ground Penetrating Radar is good for detecting contrasting layers and determining the depths of layers.

GPR is the only means of determining the depths of layers without excavation, because it is capable of producing a vertical profile of a site.

Peters Square 1

Evidence suggested that there might be a small earthen enclosure in the above farm field in Pickaway County, even though it was invisible from the air. Dr. Jarrod Burks used his instruments to create the below map of what was later called Peter’s Square.  The electrical resistance meter even showed where the gateway to the ceremonial site was located.

Peters Square 2

In an attempt to find out more about how and when the ceremonial site was used, Dr. Burks discovered another earthwork.  Neither of these earthworks was previously known to science.

Peters Square 3

These same technologies are being used on larger complexes with stunning effect. More and more is being learned about this fascinating Native American culture each year.

However, it is not only for scientific purposes that these sites must be preserved. The earthworks of the Hopewell Culture are a vitally significant part of American history. Also, these earthworks were sacred sites to Native Americans, and still are, to many people. Everyone must do what they can to help save what is left of these ancient monuments from the greatest threats they face today…

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