Chronology of the Inca expansion in the Cordillera de Vilcabamba (Peru)
Head: prof. Andrzej Rakowski
Duration: 2021-2023
Financial support: National Science Centre, Poland, grant UMO-2020/37/B/HS3/01622
Dissemination of scientific results
Articles
Ancapichun S, Pawlyta J, Rakowski A, Sieczkowska D. Influence of air parcels from northern and southern hemisphere on radiocarbon-based Inca chronology. Radiocarbon 64(6), 2022. https://doi.org/10.1017/RDC.2022.87
Ziółkowski M, Pawlyta J, Sieczkowska D, Rakowski A. Machu Picchu in the Context of the Expansion of the Inca State: Between Historical and Radiocarbon Chronologies. Springer Nature Switzerland AG 2022. https://doi.org/10.1007/978-3-030-92766-0_3
Events
- Wystawa „Poza tym, co widzialne. Teledetekcja i skanowanie laserowe w polsko-peruwiańsko-włoskich badaniach w Machu Picchu” (połączona ze spotkaniem projektowym 25.05.2022)
Patrz także: dodatkowe informacje, zdjęcia 1, zdjęcia 2, agenda spotkania. - Wystawa „Capacocha, podążając za bóstwami Inków”
Patrz także: Technologia pomaga odkrywać tajemnice Inków - relacja, plakat, Odkrywca mumii z Ampato na Politechnice Śląskiej, Dama z Ampato. Podążając za bogami Inków - obejrzyj na youtube.
Abstract
Due to the fact that currently available research tools from archaeology to history are not able to unequivocally help in answering the question about the Inca expansion in the Cordillera Vilcabamba area, exact sciences come to the rescue. According to a chronological scheme, based mainly on Spanish chronicles, the imperial phase of the Inca State was rather short, and began with the ascension to power, around AD 1438, of Pachacuti Inca Yupanqui, the ninth sovereign according to the so-called traditional list of Inca rulers. He and his successors, extended the State first to the North-West of the capital city of Cusco to present-day Ecuador and then to the south-east to the territories of what is now Bolivia, Argentina and Chile. According to this model, the Inca Empire lasted ca. 100 years. Although the historical chronology is the most accepted version of events it does not mean there are no divergent models. Some authors have questioned the historical validity of the whole Inca dynastic list, or, at least, the duration and chronological position of the reigns of the sovereigns in the list and the deeds that were attributed to them. The project aims to reconstruct historical events from the period of expansion of the Incas state in the pre-conquest period and is to help answer the question about how Inca supremacy spreads in the key region of Cordillea Vilcabamba. The studied area was extremely important for both political and economic reasons, because it was a kind of link between Amazon and the capital of the state, that is Cusco. A thorough chronology of the entire process will be developed to reconstruct historical events. To reconstruct this in detail, we will use radiocarbon data analyses, which, interpreted in the right way, will allow us to determine expansion routes and their time frames. Organic samples from excavations in the region of both the Machupicchu National Archaeological Park and other strategic sites from the Inca viewpoint will be subjected to radiocarbon analysis. Samples taken from properly selected excavation contexts will allow us to capture the moment when the Incas entered the given position, which, in turn, confronted with data from other positions, will allow us to simulate the development of events from nearly 600 years ago. Due to the lack of written sources from this period, it is the only possible tool that will allow us to discover historical truth. Due to the development of AMS radiocarbon dating technology, the level of detail in the results obtained will most likely be sufficient to perform this type of analysis.
Research methodology
The research methodology for the first part of the project is dictated by the methodology of archaeological research of Peruvian partners. The Polish side will not be responsible for the implementation of archaeological research, but only for radiocarbon analysis of the samples found. However, when it comes to the methodology of archaeological research in Peru, these are usually wide-area studies with a distinction between cultural layers and the so-called survey excavations are often used (trincheras and calas). Thanks to this research methodology, it will be possible to assign the obtained samples to individual cultural layers, which, when there will be enough samples obtained in one trench, will allow for later Bayesian analysis, assuming that at least one sample for analysis from each cultural layer.
Samples will be obtained in such a way as to prevent contamination at all levels from collection to delivery to the laboratory.
The selection of excavation sites and in particular excavation units for the years 2020-23 was conducted in consultation with Peruvian-Polish specialists (PANM and CEAC) in terms of chronological subjects. Polish experts have the status of participants and consultants in research conducted by the Park (Peruvian law does not allow independent work of foreign archaeological missions in the Machu Picchu National Archaeological Park). The competences of Polish experts include, in particular, supervision of stratigraphy and sampling for radiocarbon analysis.
All contexts will be documented in accordance with the principles of Peruvian documentation (because the Peruvian side is responsible for their excavation), all contexts will be photographed and samples measured in accordance with the principles used by the Peruvian side. The Polish side will supervise sampling in such away that they will not be damaged. For this purpose, employees will be trained in the proper handling of radiocarbon dating material and will be equipped with specially prepared monument cards, filled in when possible organic elements suitable for radiocarbon analysis are found (the most popular organic finds including the region includes pieces of coal, animal bones, seeds, charred vegetables).
Standard chemical pre-treatment for different kinds of samples (plant material, bones, leather etc.) will be used for determination of radiocarbon concentration using an AMS system consisting of several successive stages. In this procedure, four main stages can be distinguished – preliminary chemical preparation, combustion of the sample, carbon dioxide purification and graphitization.
The cathodes produced in this system will be measured at tone of the AMS laboratory in Europe or USA. While, the samples for stable isotopes studies will be measured at the Silesian University of Technology of Gliwice.
