Lake Petén Itzá, northern Guatemala, lies within a hydrologically closed basin in the south-central area of the Yucatán Peninsula, and was drilled under the auspices of the International Continental Scientific Drilling Program (ICDP) in 2006. At 16°55′N latitude, the lake is ideally located for study of past climate and environmental conditions in the Neotropical lowlands. Because of its great depth (>160 m), Lake Petén Itzá has a record of continuous sediment accumulation that extends well into the late Pleistocene. A key obstacle to obtaining long climate records from the region is the difficulty of establishing a robust chronology beyond ∼40 ka, the limit of 14C dating. Tephra layers within the Lake Petén Itzá sediments, however, enable development of age/depth relations beyond 40 ka. Ash beds from large-magnitude, Pleistocene-to-Holocene silicic eruptions of caldera volcanoes along the Central American Volcanic Arc (CAVA) were found throughout drill cores collected from Lake Petén Itzá. These ash beds were used to establish a robust chronology extending back 400 ka. We used major- and trace-element glass composition to establish 12 well-constrained correlations between the lacustrine tephra layers in Lake Petén Itzá sediments and dated deposits at the CAVA source volcanoes, and with their marine equivalents in eastern Pacific Ocean sediments. The data also enabled revision of eight previous determinations of erupted volumes and masses, and initial estimates for another four eruptions, as well as the designation of source areas for 14 previously unknown eruptions. The new and revised sedimentation rates for the older sediment successions identify the interglacial of MIS5a between 84 and 72 ka, followed by a stadial between 72 and 59 ka that corresponds to MIS4. We modified the age models for the Lake Petén Itzá sediment sequences, extended the paleoclimate and paleoecological record for this Neotropical region to ∼400 ka, and determined the magnitude and timing of CAVA eruptions.
Bibliographical noteFunding Information:
We are extremely grateful to the agencies and individuals in Guatemala who provided assistance to this project. They include: Universidad del Valle, Universidad San Carlos, Ministerio de Ambiente y Recursos Naturales, Consejo Nacional de Areas Protegidas, Instituto de Antropología e Historia, Autoridad Para el Manejo y Desarrollo Sostenible de la Cuenca del Lago Petén-Itzá, Wildlife Conservation Society, Alex Arrivillaga, Cathy Lopez, Margaret Dix, Michael Dix, Margarita Palmieri, David, Rosita, & Kelsey Kuhn, and the staff at La Casa de Don David, Lico Godoy, Tony Ortiz, Franz Sperisen, Luis Toruño, Julian Tesucún, Melisa Orozco, Silja Ramirez, Gabriela Alfaro, and Jacobo Blijdenstein. We also thank our many collaborators from University of Florida, University of Minnesota (Minneapolis/Duluth), Geoforschungszentrum (Potsdam), Swiss Federal Institute of Technology (Zurich), Université de Genève, as well as the personnel of DOSECC (Drilling, Observation and Sampling of the Earth's Continental Crust). Drilling was funded by grants from the US National Science Foundation (ATM-0502030) , the International Continental Scientific Drilling Program , the Swiss Federal Institute of Technology , and the Swiss National Science Foundation . We thank LacCore personnel Kristina Brady, Amy Myrbo and Anders Noren for help with core description and curation. This project was funded by the Deutsche Forschungsgemeinschaft (DFG) with the grants KU2685/3-1 and SCHW671/16-1 . For sampling of proximal tephras in the past, preparation of the tephras in the lab and assistance with the chemical analyses, we thank Karen Strehlow, Dagmar Rau, Armin Freundt, Walter Hernandez, Carlos Pullinger, Jan Fietzke, Fuo Lung Lin, and Mario Thöner. Finally, we thank Neil Roberts, Karen Fontijn and Roberto Sulpizio for helpful reviews and edits that strengthened the paper.
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- Explosive volcanism
- Petén Itzá
Continental Scientific Drilling Facility tags