Ground‐penetrating radar survey of the Sny Magill Mound Group, Effigy Mounds National Monument, Iowa

Abstract

A ground-penetrating radar (GPR) survey of 101 mounds at the Sny Magill Unit of Effigy Mounds National Monument, Iowa, demonstrates that GPR can be an effective tool to evaluate the structure and condition of mounds without damaging them. Ideal survey conditions and improved processing technology allow for the identification of strata within the mounds, as well as areas of post-construction disturbance and possible archaeological features within the mounds. Provisional interpretations indicate that 60 are intact conical mounds with minimal post-construction disturbance, and two show very strong evidence of containing interior burial platforms; 29 are badly damaged by non-cultural or cultural activity; two are probable non-cultural mounds; nine are reasonably intact linear and effigy mounds; one is an excavated effigy mound. GPR and other remote-sensing techniques are highly recommended for mound investigation, but wherever possible such techniques need to be coordinated with mound excavation so as to test the remote-sensing results.

The Invisible Moats of the Mun River Valley, Ne Thailand: The Examination of Water Management Devices at Mounded Sites Through Ground Penetrating Radar (Gpr)

“…Again, a programme of geophysical prospection and targeted archaeological excavation would be useful here to test this idea. As Whittaker and Storey (2008) and Persson and Olofsson (2004) argue, GPR and other non-destructive geoarchaeological methods need to be a part of a process which incorporates additional geophysical methods, alongside destructive methods of analysis such as excavation to generate a holistic approach to investigating mound sites. Despite the difficulties, the success of identifying some features at BNW was encouragement for taking the GPR to investigate the NHR site.…”

“…Traditionally, GPR is used in survey stages of archaeology as a means to locate sites or to determine their extent. GPR has been applied to mound sites in Europe and the Middle East, with empha-sis on identifying large scale features such as burial chambers and changes in sediment deposition (see Forte and Pipan 2008, Persson and Olofsson 2004, Sarris et al 2013, Urban et al 2014, Whittaker and Storey 2008. The use of GPR on mound sites in these studies was limited by the depth and density of the sites, with researchers emphasizing the need to combine GPR with other geophysical methods.…”

“…There have been limited expressions of the Historic and modern periods in the excavations at BNW. The site's highly complex structure and archaeology makes fine grained GPR survey very challenging, however, as Forte and Pipan (2008), Persson and Olofsson (2004) and Whittaker and Storey (2008) have demonstrated, the examination of large scale features, such as water management devices, is likely to be much more rewarding at highly stratified mounded sites.…”

Geophysical Detection and Assessment of Leveled Mounds: An Example from the Upper Mississippi Valley

“…Likewise, McCullough's (2018) geophysical survey of the extant Nadine Mound Group (11HE69) on the Mississippi River bluffs in western Illinois detected central (presumably mortuary) features and possible accretional mound stages. On a low terrace in the Mississippi River valley in northeast Iowa, Whittaker and Storey's (2008) ground-penetrating radar study of 101 extant Middle and Late Woodland mounds at the Sny Magill Mound Group (13CT18) identified internal anomalies in most mounds.…”