Reworked volcaniclastic deposits from the Usumacinta river, Mexico: A serendipitous source of volcanic glass in Maya ceramics

Abstract

AbstractThe origin and distribution of volcanic glass temper in Maya ceramics has attracted the attention of Mesoamerican archaeologists for the last 80 years. Several Quaternary volcanoes, particularly those in the Central American Volcanic Arc (CAVA), are proposed as the source of tephra in the Maya region, however, a continuous stratigraphic record of this tephra deposit is still lacking. A reworked volcaniclastic deposit (9 ± 2 ka) was located in the Usumacinta River fluvial sequence from Tabasco State, Mexico. This material has been found in ceramics from the Tierra Blanca archaeological site, which developed from the Formative to Late Classic Maya period. Cross‐bedding sedimentary structures and amygdaloidal texture in pumice indicate the influence of the fluvial environment and the weathering exposition of the volcanic deposit. The comparative geochemical and petrographic features provide the first evidence that this volcanic ash “outcrop” was used for local ceramic manufacture. The volcanic event that produced the tephra is difficult to identify due to the dynamic sedimentary environment that obliterated and mixed the original mineralogy and geochemistry. Eruptions with rhyolitic magma are the most probable candidates. This assumption contradicts the widespread hypothesis that the tephra of El Chichón volcano is the source of volcanic glass in Classic Maya ceramics.