Towards the use of archaeomagnetism as an archaeological dating tool for South America

Author(s)

Maximiano, Paulo F. ; Poletti, Wilbor ; Mathias, Grasiane L. ; Rocha, Mikaelly G. ; Trindade, Ricardo I. F.

• Document type: Journal article
• Source: Journal of South American Earth Sciences; v. 144, p. 14-pg., 2024-07-23.

Abstract

Dating archaeological materials is essential to understand time and rate of changes in different civilizations. For this purpose, different dating methods are used in several materials, including organic remains, sediments, and ceramics. Archaeomagnetic dating is a developing dating tool that has been improving rapidly due to the advances in geomagnetic model curves. The premise of this method is to compare the inclination, declination, and intensity of the geomagnetic field recorded by burnt archaeological materials (i.e., bricks, kilns, burned floors, pit ovens, soils, ceramics, slags), with mathematical models that describe the evolution of the Earth's magnetic field. Different regional geomagnetic models have been built based on local data that allow the application of this dating method, whereas for regions where regional models are lacking, global geomagnetic models are used. In any case, it is essential to assess the intrinsic uncertainties of geomagnetic models to properly evaluate the feasibility of the archaeomagnetic dating. In this context, this work evaluated global geomagnetic models for South America over the last 2000 years, to select the most appropriate statistically for dating purposes. Based on Casas and Tema (2019), a thorough assessment of the age uncertainties of the models was carried out. The statistical analyses of the magnetic parameters of the selected models regarding high-quality data were integrated to the intersection analyses of different magnetic parameters. From this result, this study suggests a geomagnetic multi-model approach as the best configuration for archaeomagnetic dating for South America. (AU)

• FAPESP's process: 16/06114-6 - The Neoproterozoic Earth System and the rise of biological complexity
• Grantee: Ricardo Ivan Ferreira da Trindade
• Support Opportunities: Research Projects - Thematic Grants