GPR investigations at an Inca‐Spanish site in Argentina

Abstract

We present the results of a GPR prospecting carried out at the archaeological site of Batungasta, in the NW region of Argentina. This site was established by the Incas in the 14th century and was later occupied during the Spaniard conquest. Environmental information obtained at this arid zone led us to postulate that parts of the site buildings had been seriously damaged and buried by seasonal flood events as well as aeolian sedimentation. Therefore, we considered applying the GPR method to investigate the existence of buried remains, their architectural characteristics and to provide further evidence about the flows that possibly affected them. This method seemed suitable to attain these goals since it usually provides a good detection capacity for architectural structures and layers in dry environments, as well as good quality maps of the soil. Seven sectors of the site were surveyed using a GPR constant‐offset methodology and 500 MHz antennas. The analysis of the data allowed recognizing electromagnetic patterns that could be associated to the existence of walls. In six of the seven sectors, enclosures formed by rock‐earth and earth walls were detected and mapped, confirming Incaic‐Spanish and Spanish structures, respectively. A sedimentary layer produced by a large flood that covered the structures was detected and mapped, providing evidence of this kind of event and its influence on the site. The maps of this layer were also useful to indirectly visualize the 3D shapes of the discovered walls, which were unclear in many sections of the data and to detect additional anthropogenic structures with very bad preservation conditions. These structures had not been previously identified from analysis of the data sections due to the confusing aspect of the reflections produced at their irregular boundaries.

Automatic detection of mud‐wall signatures in ground‐penetrating radar data

“…The GPR data were acquired by Martino et al (2006) and Bonomo et al (2009, 2013) using a Sensors & Software Pulse EKKO PRO GPR system and 500‐MHz (nominal frequency) antennas, disposed in CO mode. The acquisition parameters were defined mainly by considering the characteristics of the prospected sectors and the objectives of the prospecting (e.g.…”

“…Then, in the GPR radargrams and time slices, the electromagnetic responses of these structures tend to show low and variable amplitudes and shapes, which significantly complicate their identification. Examples of images with these characteristics have been obtained for tapia and adobe remains in very different archaeological sites, such as pre‐Inca and Spaniard villages in Argentina (Bonomo et al, 2012; Bonomo, Osella, & Ratto, 2013; Martino, Bonomo, Lascano, Osella, & Ratto, 2006), an Early Bronze Age site located in the Syrian Middle‐Euphrates valley (Novo, Solla, Fenollós, & Lorenzo, 2014) and in Qocho City, China (Shi et al, 2015).…”

Magnetic gradient and ground penetrating radar prospecting of buried earthen archaeological remains at the Qocho City site in Turpan, China

“…GPR 2D or 3D surveys provide depth information of the archaeological remains. Many successful application cases of both technologies are reported in the detection of stone structures, wooden structures, ditches, and so on (for example, Bonomo, Osella, and Ratto (); Capizzi et al (); Conyers (); Gaffney et al (); Kadioglu (); Di Mauro et al (); Scardozzi, Giese, and Hübner (); Thompson and Pluckhahn ()). For the detection of earthen remains, there are only a limited number of papers from a ceremonial site of Cahuachi in Peru, which lies in the desert environment (Masini et al ; Lasaponara et al ).…”

Utilities detection through the sum of orthogonal polarization in 3D georadar surveys

“…Applications of this method have been expanded during the years to a wide variety of areas, such as environmental sensing (Seol et al 2007;Knight 2001), landmine detection (Acheroy 2007;Lualdi and Zanzi 2005;Sato et al 2004;Zanzi et al 2002), archaeological investigations Bonomo et al 2013), geology (Beres et al 1999;Saintenoy et al 2013;Sénéchal et al 2013) and civil engineering (Binda et al 2004;Hugenschmidt et al 2011;Donohue et al 2011).…”