NSFGEO-NERC: Collaborative Research: MexiDrill: Developing a 350,000 year record of climate and environmental change in tropical North America

Lead Research Organisation: University of Oxford
Department Name: School of Archaeology


The primary scientific objective of this joint NSF-GEO/NERC proposal is to obtain a continuous, high-resolution record of past changes in climate and volcanism in the Mexico City region over the last 350,000 years. We will analyse a recently recovered ~350 metre-long core from the Lake Chalco basin on the southern outskirts of Mexico City. This sediment sequence will be among the longest archives of climate, environment, and biota from a region presently lacking such records. Information obtained from these cores will help understand the mechanisms that caused past climate shifts, which is critical for evaluating impacts of ongoing and future climate change. Mexico is projected to become drier in the coming decades-centuries in response to ongoing climate change, and these anthropogenic changes will be superimposed on natural variability in climate systems that are not fully understood. This project will extract information on the temperature and precipitation over the last 350,000 years to evaluate the drivers of the climate. The Chalco sedimentary sequence also provides a unique record of the explosive volcanism in the Mexico City region, with ash from more than 150 volcanic eruptions preserved. These volcanic ash layers are likely to be from the major stratovolcanoes that surround Mexico City and the extensive monogenetic field situated in the southern part of the city. We will use these eruption deposits to obtain a chronology for the core and establish the magnitude and frequency of past eruptions. This information on the long-term history of these volcanoes will be invaluable for hazard and risk assessments for this densely populated region.

Planned Impact

Sediments from Lake Chalco hold geologic, paleoenvironmental, and palaeobiological information of value to the global scientific community, and directly relevant to the >20 million people living in the Basin of Mexico. Results of this project will contribute to an improved understanding of climate and hydrological balance in one of the most densely populated urban centers on Earth. Hydrological balance impacts agriculture and drinking water as well as affecting vulnerability to disease. We will feed this information back to the authorities through our colleagues at the National Autonomous University of Mexico (UNAM) in Mexico City.

Our work will provide an improved fundamental understanding of the rates of past volcanism, and impacts of past eruptions of the volcanoes in and around Mexico City. We will work with our colleagues at UNAM to inform revised assessments of volcanic hazard and risk. These assessments will be used by National Civil Protection System (SINAPROC) to develop evacuation plans, for future eruption scenarios; and are used to inform long term urban and infrastructure planning.

Residents of Mexico City, including visitors to the region, tour guides and tourist agencies; and people generally interested in climate and volcanoes will all benefit from the additional knowledge of the past climate and the eruption histories of the volcanoes surrounding Mexico City. For public outreach, our team will: 1) incorporate field guides from Mexico into the 'Flyover Country' mobile app, which will be available in English and Spanish, and 2) develop a half hour documentary for broadcast on the USA Pubic Broadcasting Service (PBS) network and dissemination through various educational channels.
Description We have described, dated and chemically characterised the deposits of the major explosive eruptions of the largest volcanoes surrounding Mexico City (published in Sunye-Puchol et al., 2022) and the Chalco basin. These constraints on the deposits provide a better understanding of the timescales of large eruptions from Popocatépetl, Iztaccíhuatl and Tláloc-Telapón. These data have been used to interpret the data from the Chalco (MexiDrill) core and have aided the construction of the age model for the core.
Exploitation Route This data will be useful for those working on mitigating the volcanic hazards in the densely populated Mexico City and surrounding region.
Sectors Education


Democracy and Justice

Description Community Established Best Practice Recommendations for Tephra Studies - from Collection through Analysis.
Geographic Reach Multiple continents/international 
Policy Influence Type Influenced training of practitioners or researchers
Description NEIF facility access
Amount £40,661 (GBP)
Funding ID 2407.0321 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 06/2021 
Title Glass chemistry data from Popocatépetl, Iztaccíhuatl and Tláloc-Telapón volcanoes in Central México 
Description Major element glass chemistry data 
Type Of Material Database/Collection of data 
Year Produced 2021 
Provided To Others? Yes  
Impact None yet 
URL https://www.sciencedirect.com/science/article/pii/S0377027321002420?via%3Dihub#s0190
Title Radiocarbon measurements determined using an accelerator mass spectrometer 
Description Radiocarbon data from the MexiDrill core. These have been uplaoded to the National Geoscience Data Centre (NGDC) 
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? No  
Impact The age depth model for the MexiDrill core. 
Description NSF partners of the MexiDrill project 
Organisation University of Minnesota, Duluth
Country United States 
Sector Academic/University 
PI Contribution We are working together on the larger MexiDrill project. We are helping to develop the chornology for the core.
Collaborator Contribution Sedimentology and paleoenvironmental reconstruction.
Impact Publications and conference abstracts listed in relevant sections.
Start Year 2018
Description UNAM 
Organisation National Autonomous University of Mexico
Country Mexico 
Sector Academic/University 
PI Contribution Glass chemistry data
Collaborator Contribution Samples and field work support
Impact Paper listed in the publications section
Start Year 2018
Description Natural History Museum volcano outreach event 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact We had a stand at the volcanoes public outreach event in the Natural History Museum, London on Monday 7th January. Our team had a stand focussed on 'Dating the Past', with actives and information on ways in which we date sedimentary sequences and events (such as tephrochronology, radiocarbon dating). We had a game that challenged participants to arrange 3-5 events in chronological order, e.g., building of the Egyptian pyramids, advent of farming, first ceramics; and we had slices of wood for children to work out how old the tree was when it was cut down that they could decorate. More than 180 slices were handed out and decorated.
Year(s) Of Engagement Activity 2023
URL https://twitter.com/OxfordTephra/status/1612374919777501185
Description Public presentation, Fukui prefecture, Japan 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Gave a general presentation on tephrochronology to the general public in Japan. This presentation was translated, and featured aspects of my research. I was invited to this event, which was scheduled to mark the 5th anniversary of the Varve Museum in Fukui, Prefecture.
Year(s) Of Engagement Activity 2023
URL http://varve-museum.pref.fukui.lg.jp/en/
Description Short course at Geological Society of America meeting 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Around 60 postgraduate research students, postdocs and other researchers from mainly the US attended a virtual workshop organised by Dr Amy Myrbo (collaborator on the proposal) and Dr Maarten Blaauw (PI on the proposal). The workshop attracted around 60 participants and was held over 4 multiple-hour sessions. Student reviews were highly positive; they reported better knowledge of Bayesian age-modelling of deposits dated using radiocarbon and other dates (e.g., 210Pb).
Year(s) Of Engagement Activity 2021
URL https://maarten14c.github.io/GSA_agemodeling/intro.html