Tingambato

Resumen: Este artículo presenta una revisión de estudios cerámicos en Tingambato, Mi-choacán, intentando solucionar el problema de inconmensurabilidad entre ellos y propone un primer acercamiento a la caracterización petrográfica de la cerámica. Para el análisis se aplicaron las técnicas de fluorescencia por inducción de luz ultravioleta y análisis pe-trográfico con láminas delgadas; la primera fue empleada como una prueba experimental para identificar diferencias en una muestra bastante grande para después reducirla a un número viable para la laminación, la cual resultó exitosa. La petrografía en láminas delga-das aporta información sobre composición mineralógica, particularidades en la técnica de manufactura y una primera aproximación que permite proponer regiones de extracción de materiales. Lo que da una nueva perspectiva sobre los procesos de manufactura que emplearon los ceramistas de este importante sitio arqueológico. Abstract: This paper presents the different researches of the ceramics of the Tingambato site, Michoacan, Mexico, in order to solve the typological problem between different authors. We used Ultraviolet-Induced Visible Fluorescence and petrographic analyses by means of thin sections techniques; the first technique was used as an experimental technique to identify differences in a very large sample, in order to reduce it so it could be used for thin section analysis. The petrographic analysis by thin section gives us information about the mineralogical composition, craft production and a first approach to the possible

A través de la historia, los rituales y formas de enterrar a los muertos han variado entre grupos culturales y regiones. Mesoamérica y particularmente su área occidente, no fueron la excepción. En este territorio se han descubierto tumbas acompañadas de ofrendas que datan desde el periodo formativo (Oliveros, 2004) y que con el paso del tiempo constituyeron verdaderas tradiciones funerarias.

La zona arqueológica de Tingambato se encuentra en el límite sur del poblado que lleva el mismo nombre en el estado de Michoacán. Su topónimo puede derivar de Tinganio que en lengua tarasca significa ‘’lugar donde termina el fuego’’, haciendo referencia a las condiciones geográficas del lugar: donde comienza la tierra fría y termina  la tierra caliente (Piña and Ohi, 1984). Fue en este sitio donde, en 1978 los arqueólogos Román Piña Chan y Kuniki Ohi descubren la Tumba I, la cual contenía los restos de entre 50 y 124 individuos (Lagunas 1987: 11) , así como un gran número de ofrendas.

En el año de 2011 se descubrió una segunda tumba de bóveda con un techo a manera de cúpula, construida a base de piedra laja y tierra (Landa 2011a). La Tumba II contenía los restos de un importante personaje, pues estaba acompañado de un ajuar funerario compuesto por miles de elementos elaborados en conchas marinas y piedras verdes.  Desafortunadamente, el techo de la tumba sufrió un colapso parcial, por lo que los materiales se recuperaron prácticamente descontextualizados, por lo que en este trabajo se presenta una propuesta de distribución de los ornamentos en relación a la persona.

a)Identificar las especies marinas y los minerales en que se trabajaron las piezas lapidarias. b) Realizar una clasificación morfológica y funcional bajo los parámetros establecidos por Lourdes Suárez (Suárez, 1977) de todos los elementos encontrados en la tumba y que al ser analizados en conjunto y no como partes aisladas, se podrá interpretar de manera integral el contexto arqueológico. c) Analizar espacialmente los objetos en relación al área del cuerpo donde se localizaron, integrando nuevos datos que se han obtenido sobre los restos óseos. Lo que nos permitirá proponer una interpretación que pueda derivar en una propuesta de reconstrucción del ajuar funerario y hablar de la persona depositada en la Tumba.

Poster presented at the “9th Congress of the Balkan Geophysical Society (BGS2017)
Antalya, TURKEY 5-9 November 2017.

Tingambato was one of the major archaeological sites in west Mexico (latitude 19º30´N, longitude 101º51´W at an elevation of 1930 m asl.) during the Classic period, but unfortunately we know little about its particular chronology. The geology of the site is dominated by recent volcanic activity (Pliocene/Quaternary) and the bedrock is composed of young volcanic basaltic-andesite, andesite and dacite rocks and the volcanic ejects develop soils characteristics classified as Andisols. In this study we present the results of GPR and ERT measurements performed on Tingambato site in May 2017. Site description and objectives of the Study The Tingambato archeological site is located in Michoacán State, Western Mexico. It flourished during the Classic and Epiclassic Periods (ca. 200 to 700/750 AD) and was then one of the largest sites in Western Mexico. It is situated in a region known as the Michoacán-Guanajuato volcanic field, which is part of the Trans-Mexican Volcanic Belt, at latitude 19°30´N, longitude 101°51W and at an elevation of 1930 m asl. It is surrounded by Pliocene/Quaternary volcanic highlands (< 2700 m asl) of basaltic andesite, andesite and dacite rocks. The subsurface of the Tingambato site is composed of volcanic sediments of mixed grain size, ranging from boulder to silty-clay. A weathered and thinner soil layer, 30 to 50 cm thick, covers these thick alluvial sediments. The first major archeological investigation of the Tingambato site was conducted during the 1970´s. But, in spite of extensive excavation, little is known about the site itself and the timeline to its history. On the basis of architectural remains, it was proposed that the Tingambato site was occupied in two periods: first between AD 450 to 600 and secondly between AD 600 and 900. The former period was characterized by the construction of the ceremonial center and the last, by the building of the " Juego de Pelota ". Moreover, a recent study proposed three stages of construction between AD 200 and 700/750. The first stage is characterized by the construction of the western and eastern buildings as well as the surface leveling; the second by the construction of the great platform, the tombs, the " patios hundidos " (fills encased by stones) and the introduction of the talud-tablero in the rooms; and the third one, by the covering of the talud-tablero. Unfortunately, none of these chronologies relies on absolute dates (e.g. radiocarbon), thus leading to speculation about them. In order to answer this question we have conducted many GPR and ERT campaigns in different areas of Tingambato site since 2013. According to the preliminary geophysical results obtained during 2013 and 2014 we designed two archeological excavations in 2015 and 2016 which helped us to confirm the first radiocarbon dates and starting to build a solid chronology. The latter results conducted us to undertake another geophysical campaign in May 2017. The objectives were to detect the foundations (ancient buried walls) and cavities (tombs) and define their geometry. Geophysical field survey and data processing In May 2017 the surveyed area was selected according to the hypothesis of the archaeologists, and the " Plataforma Principal " (Figure 2) was considered as a good location for testing GPR and ERT methods and comparing their ability to image walls and/or tombs. A survey grid of 12 x 37 m was established to collect 2D GPR parallel profiles spaced with a small interval of 25 cm (49 profiles oriented east-west). The GPR survey was performed using SIR-3000 system equipped with a 200 MHz shielded antenna and a trace trigger interval of 5 cm. Additionally, dipole-dipole array of 2D ERT parallel profiles spaced of 2 m (7 profiles oriented east-west) were carried out to support the GPR interpretation. The ERT system (McOHM-21, Model 2116, OYO Corp.) was equipped of 16 electrodes spaced of 2.5 m. The GPR data were processed by using the ''Radan7'' software from GSSI and the " RadLab " in-house software written in Matlab and developed at Institut de physique du globe de Strasbourg/Université de Strasbourg (for more details see Ortega-Ramirez et al., 2017). The velocity of the electromagnetic (EM) waves was estimated by modeling different diffraction hyperbolas observed in the 2-D GPR profiles. We have found an average value of the EM velocity of 0.085 m/ns, which has been used to convert time to depth in all collected profiles. The ERT profiles were modeled and inversed by using the Res2Dinv and Geotomo Software. Results and discussion Two GPR reflection profiles from the grid of " Plataforma Principal " are shown in Figures 2 and 3 (see Figure 4 for their location), where a prominent diffraction zone with higher reflection becomes evident starting at a depth of 1 m (see white arrows in Figure 3 and 4). The diffraction zone of GPR profile-16, shown by white arrow at 11 m horizontally in Figure 3, coincides with the resistive zone (in red) of the ERT profile-3 of the same figure. The black arrow of GPR profile-16 indicates a curved reflection of high amplitude located at 34 m horizontally. The same reflection of GPR profile-21, which is 1 m apart from profile-16, becomes nearly horizontal (black arrow in Figure 4). The amplitude map (depth slice) at a depth of 2.10 m is presented in Figure 5. The red anomalies probably are related to ancient buried walls and cavities and define their geometry. The two yellow squares (2m by 2m), in this figure, indicate two zones centered at 9 m and 34 m horizontally (from East to West), to be excavated in the near future. The excavations are in progress and the results will be soon presented. Conclusions This study confirms that the combination of GPR and ERT methods can be successfully used in archaeological investigation in order to characterize the depth and dimensions of burial targets. The amplitude maps (depth slices) of 3-D GPR profiles combined with ERT images help us to target those anomalies and try to look for architectural remains of the Tingambato second stage in order to obtain information about construction techniques and have material for absolute dating, which will complete the site chronology. The diffraction zone which starts at a depth of 1.5 m and having a width of 5 m (see GPR profiles on Figures 3 and 4) might indicate the presence of wall remains. The results can be used to plan a deeper excavation on the same site. Figure 1: Location of the Tingambato Site, Central México, Michoacán-Guanajuato Volcanic Field. Wall remains in the investigated area and acquisition with a 200 MHz antenna. Figure 2: Location of geophysical surveyed area (12m by 37m) of " Plataforma Principal " , in Tingambato, prospected by GPR and ERT methods in May 2017. Figure 3: The processed GPR profile-16 and the ERT profile-3 (from East to West) on the same place. Both profiles are 4 m from the first profile (see green line in Figure 5 below). Figure 5: Figure 4: Amplitude map at 2.10 m depth (zone of 12m by 37m). The green and white lines show the profiles 16 and 21 (from East to West, see Figures 3 and 4) which are 4 m and 5 m, respectively from the first profile. The GPR profile-16 (green line) coincides with the ERT profile-3 of figure 2. Yellow squares indicate two zones (2m x 2m), centered at 9 m and 34 m (from East to West), to be excavated.

This study presents the results of a GPR investigation carried out at the archeological site of Tingambato, in the state of Michoacán, Mexico. The aim of the study was to detect the presence of ancient buried structures, such as walls or graves and determine their geometry in order to help establish the timeline history of the site. It also aimed at producing amplitude maps and/or reflection profiles of the location and dimensions of burial targets. The survey was conducted in four areas using the 200 MHz antenna, and in one area the study was performed with a 900 MHz. Site description and objectives of the Study The Tingambato archeological site is located in Michoacán State, Western Mexico. It flourished during the Classic and Epiclassic Periods (ca. 200 to 700/750 AD) and was then one of the largest sites in Western Mexico. It is situated in a region known as the Michoacán-Guanajuato volcanic field, which is part of the Trans-Mexican Volcanic Belt (cf. Figure 1), at latitude 19°30´N, longitude 101°51W and at an elevation of 1930 m asl. It is surrounded by Pliocene/Quaternary volcanic highlands (< 2700 m asl) of basaltic andesite, andesite and dacite rocks. The subsurface of the Tingambato site is composed of volcanic sediments of mixed grain size, ranging from boulder to silty-clay. A weathered and thinner soil layer, 30 to 50 cm thick, covers these thick alluvial sediments. The first major archeological investigation of the Tingambato site was conducted during the 1970´s, but, in spite of extensive excavation, little is known about the site itself and the timeline to its history. On the basis of architectural remains the Tingambato site was occupied in two periods: first between AD 450 to 600 and secondly between AD 600 and 900. The former period was characterized by the construction of the ceremonial center and the last, by the building of the " Juego de Pelota ". Moreover, a recent study proposed three stages of construction between AD 200 and 700/750. Unfortunately, none of these chronologies relies on absolute dates (e.g. radiocarbon), thus leading to speculation about them. In order to answer this question we conducted GRP survey in different areas of the site (Figures 2, 3 and 4). The objectives of this study were to detect the foundations (ancient buried walls) and cavities (tombs) and define their geometry, as well as the way to correlate construction style and depth with relative chronological buried structures, using 2-D and 3-D GPR profiles. The surveyed areas were selected according to the hypothesis of the archaeologists, i.e. areas with higher possibilities to contain structures likely to be walls of anthropogenic origin. GPR data acquisition and processing The GPR survey was performed using SIR-3000 system, equipped with middle (200 MHz) and high centre frequencies (900 MHz) shielded antennae to detect ancient stone walls foundations and/or tombs at depths ranging approximately from 1 to 4.0 m. Wall remains are visible on the main platform (Figure 3), however it was assumed that there might be other walls, oriented in unknown directions, which are not visible and might belong to the first archaeological occupation. In order to remove certain types of noise and false reflection (artifacts), the GPR data were processed by using the ''Radan7'' software from GSSI and the " RadLab " in-house software written in Matlab and developed at IPGS (Strasbourg University). The processing sequence involved time-zero shift, background removal, amplitude gain (linear and/or exponential), predictive deconvolution to improve the vertical resolution, and finally band-pass filtering (100/400 MHz and 450/1800 MHz for 200 and 900 MHz antenna respectively). The velocity of the electromagnetic (EM) waves was estimated by using different diffraction hyperbolas detected in the 2-D GPR profiles. From all the diffraction hyperbolas observed in all sections, we found an average value of the EM velocity of 0.065 m/ns. This value has been used to estimate the depth of the main reflectors in all collected profiles. The GPR profiles from U1 area show a prominent diffraction zone with higher reflection becomes evident starting at a depth of 50cm (Fig. 5). A grid of 2 m x 4 m was excavated according to the findings registered in order to identify the reflectors corresponding to the recorded anomalies at " La Huerta Avocados ". In the first 10 cm of depth, pieces of ceramic and modern artifacts were discovered as well as cobles of volcanic origin with sandy-silty matrix (Fig. 6). A grid of 2 m x 2 m (Figure 7A) was excavated, no deeper than 70 cm, revealing that the first anomaly corresponds to an ancient burned anthropic floor (Fig. 7B). On the third location " Zona Hundida " (U3), the GPR profile shows a horizontal diffraction zone close to the surface, approximately 30 cm thick, above a 1 m thick layer with no reflector which in turn covers a diffraction layer (Fig. 8A). A grid of 2 m x 2 m was excavated, revealing that the first diffraction zone corresponds to the presence of a carpet of coarse gravel size volcanic rock whereas the second layer contains silty-clayed deposits mixed with contemporaneous garbage(Fig. 8B) and the third layer contains coarse rocks fragments. On the fourth location " Intra-muros " (U4), several reflectors were identified. The first one at a depth of 1.2 m, the second starts at a depth of 1.8 m and ends at 2.35 m, and extends from 2 to 14 m on the survey line (Fig. 9A), the excavation of 6 m x 2 m and 3 m deep is shown in Fig. 9B. Conclusions On the first location (U1), due to the angularity and size of the deposits, we considered that diffraction zones represent debris flow avalanche deposits that comprise friable clast-supported gravels. The clasts are derived from Sierra de Tingambato and were deposited by larger magnitude flows which in turn were emplaced as debris flow. It can therefore be deduced that the original hypothesis that the site may contain a tomb has to be overruled. On the second location (U2), the diffraction zone that starts at a depth of 1.6 m and is 2.5 m wide might indicate the presence of a wall; the results can be used to plan a deeper excavation on the same site. On the fourth location (U4) " Intra-muros " , the archeologist found some anthropic remains (an ancient floor and two walls). However, the reflection profile showed evidence of another anomaly close to and extending outside the excavation. The results of the survey can therefore be exploited in a further extended excavation.