Goodman-Martínez-Thompson correlation

Goodman-Martínez-Thompson correlation
Name	Goodman-Martínez-Thompson correlation
Other names	GMT correlation
Occupation	Chronological correlation

Goodman-Martínez-Thompson correlation is the standard correlation for converting Long Count dates of the Maya civilization into the Julian calendar and Gregorian calendar. It was proposed by J. Eric S. Thompson building on earlier work by A. E. Goodman, Thompson’s contemporaries, and formalized with contributions from Edward Thompson and Sylvanus G. Morley’s scholarly lineage, while drawing on studies by Diego de Landa, John Lloyd Stephens, Frederick Catherwood, and Teoberto Maler. The correlation underpins chronology used by institutions such as the British Museum, the University of Pennsylvania Museum of Archaeology and Anthropology, the Peabody Museum of Archaeology and Ethnology, and the Instituto Nacional de Antropología e Historia.

Background and discovery

The correlation emerged from efforts by scholars like Earl H. Morris, Alfred M. Tozzer, Sylvanus G. Morley, Ernest Thompson Seton, and J. Eric S. Thompson to reconcile inscriptions studied at sites including Copán, Tikal, Palenque, Uxmal, Chichén Itzá, Bonampak, Piedras Negras, and Quiriguá with European chronologies used by Alexander von Humboldt, Charles Darwin, C. C. Royce, and John L. Stephens. Field reports by Teoberto Maler, A. F. Bandelier, Adrián Recinos, and museum catalogues from Smithsonian Institution and Musée de l'Homme informed debates linking epigraphic readings, colonial documents like the Popol Vuh, and missionary accounts by Diego de Landa and Fray Toribio de Benavente Motolinía. The need for a precise anchor was amplified after archaeological programs by Carnegie Institution for Science, Yale University, Harvard University, and Dumbarton Oaks produced new stelae and codices.

Methodology and formulation

Formulation combined calendrical analysis used by Karl Sapper, Alfred Maudslay, Rudolf H. Schelling, and J. Eric S. Thompson with correlation techniques applied in studies by Ernest Thompson Seton and chronologies referenced by Joseph Needham. The approach matched Maya Long Count constants—baktun, katun, tun, uinal, kin—recorded at Tikal, Copán, Palenque, Calakmul, and Yaxchilan with European dates via colonial-era chronicles such as those of Diego de Landa and the Popol Vuh commentary by Rafael Girard. Key anchors invoked astronomical events like the Halley's Comet apparitions, Venus cycles analyzed in the Dresden Codex, and eclipse records discussed by John P. Lightfoot and Heinrich Brühl to derive a correlation constant placing 0.0.0.0.0 at a specific Julian day number favored by Goodman, Martínez, and Thompson.

Evidence and supporting data

Supporters cite concordance between Long Count dates at Copán and Quiriguá, lunar tables in the Dresden Codex, and synchronisms recorded with Classic-era rulers such as those of K'inich Janaab' Pakal, Yax Nuun Ahiin I, and Jasaw Chan K'awiil I. Archaeological stratigraphy from excavations by Alfred M. Tozzer, William Fash, and Tatiana Proskouriakoff produced mortuary and ceramic sequences consistent with the correlated dates. Epigraphic readings by Linda Schele, Peter Mathews, David Stuart, Simon Martin, and Nikolai Grube reinforced cross-site synchronisms, while dendrochronology from wood associated with sites studied by Adams, radiocarbon determinations pursued by S. W. Manning and Michael D. Coe further aligned with the Goodman–Martínez–Thompson constant within expected error ranges.

Criticisms and alternatives

Critics such as Arlen F. Chase, David Stuart, Peter Mathews, John H. Alden, and Kenneth Hirth pointed to discrepancies with certain radiocarbon series, variant readings in the Dresden Codex and Madrid Codex, and colonial calendar ambiguities highlighted by Rodolfo Lidia and E. Wyllys Andrews V. Alternative correlations proposed by Rolf Sinclair, Andrés Ciudad Ruiz, Sergei Rjabchikov, and John W. Hoopes draw on different eclipse identifications, revised interpretations of Diego de Landa’s list, and adjusted Long Count zero-points argued in studies at Monte Albán, Teotihuacan, and Mitla. Debates have involved institutions including the Carnegie Institution for Science, University of Texas at Austin, and Institute of Archaeology (Oxford).

Applications in Maya chronology

The correlation is used to date Classic, Preclassic, and Postclassic events involving rulers, wars, dedications, and celestial ceremonies documented at Tikal, Calakmul, Copán, Palenque, Toniná, Comalcalco, and Chichén Itzá. It underlies chronological narratives in syntheses by Michael D. Coe, William Fash, Gillespie, Simon Martin, Linda Schele, Karl Taube, and Graham Hancock-style popularizations, informs museum displays at Peabody Museum, British Museum, National Museum of Anthropology (Mexico City), and frames conservation priorities by INAH and ICOMOS-affiliated projects. The correlation guides comparative studies linking Maya events to broader hemispheric timelines involving Teotihuacan interactions, Toltec migrations, and Spanish contact documented by Bernal Díaz del Castillo.

Legacy and impact on Mesoamerican studies

The correlation established a common temporal framework adopted by scholars at Dumbarton Oaks Research Library and Collection, The Field Museum, Peabody Institute, Smithsonian Institution, Universidad Nacional Autónoma de México, and international research consortia. It enabled synthesis of epigraphy, iconography, archaeology, and archaeoastronomy in works by Tatiana Proskouriakoff, David Stuart, Linda Schele, Simon Martin, Michael Coe, and J. Eric S. Thompson’s intellectual successors. Ongoing refinements link it to radiocarbon labs such as Beta Analytic, dendrochronology centers at University of Arizona, and computational projects at Stanford University and University of California, Berkeley, ensuring the correlation remains central to reconstructing the chronology of the Maya civilization.

Category:Mesoamerican chronology