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Three lava flows (Buenavista, Xalitzintla and Nealtican) and pyroclastic density currents (Lorenzo and Pink Pumice) from two Popocatepetl Plinian eruptions were sampled for paleomagnetic dating. A detailed rock-magnetic characterization of the lavas, scoria clasts and pottery shards intercalated between the volcanic deposits was also carried out. Reliable results, both in direction and in intensity, were obtained for the Nealtican lava flow, which enabled its full-vector paleomagnetic dating using the archaeo_dating tool together with the global paleosecular variation model SHA.DIF.14 k, obtaining an age interval between 1040 AD and 1140 AD (95% probability confidence level), in good agreement with its associated 14 C age. The well-grouped paleomagnetic direction of the seven specimens from two different scoria clasts of the Lorenzo Pumice pyroclastic density current suggests that clasts were emplaced hot, at a temperature that seems to have almost completely erased the original remanent magnetization of the clasts. This fact is supported by the reheating of the underlying pottery shards, evidenced as a clear secondary low-temperature range (room temperature to 350 °C) component at the orthogonal vector plots. Similarly, the three mean clusters directions obtained for site PO-2 (Pink Pumice)-roughly concentrated around the present geomagnetic field-suggest also a high emplacement temperature. Also, the first archeointensity dating of a pottery shard within the pyroclastic density current is reported. Finally, results of the rock-magnetic and paleomagnetic dating of the last Plinian eruptions from the Popocatepetl volcano, applied to different volcanic materials (lava and pyroclastic density currents), show the usefulness of these nonconventional and alternative techniques in the study of the eruptive activity of volcanoes. which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

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An inclusive rock-magnetic and absolute paleointensity survey of the ~ 2-ka-old Xitle volcano (southerly Basin of Mexico) was undertaken to assess the faithfulness of the paleomagnetic log carried by fresh, widely exposed and well-preserved lava flows. Paleomagnetic samples from six lava flows were subjected to paleointensity analysis with a multi-method approach: the Thellier–Coe, IZZI, and multi-specimen methods. Overall mean flow PI values from flows 4–6 obtained by the Thellier-type methods used yielded 68.4 µT (σ = ± 5.6 µT), 63.9 µT (σ = ± 5.8 µT) and 61.5 µT (σ = ± 4.3 µT) for the TC, IZZI, and IZZI with CR correction methods, respectively. Although multi-specimen paleointensity results were, in general, lower than that obtained with the other methods for the same flows, that for Flow 5 (61.8 µT) was very similar to those obtained with the Thellier-type methods. Based on the results obtained, this lava flows sequence could correspond to two eruptive periods; one related with the Xitle volcano (flows 3–6), and another older (flows 1 and 2). The combined archeomagnetic dating of the different flows reinforces this hypothesis, as well as the multi-modal distribution for the age of the Xitle, proposed two decades ago. The application of stricter acceptance criteria and consideration of cooling-rate correction could slightly reduce the scattered observations. The multi-method approach employed under this study, combined with detailed rock-magnetic experiments, may definitively increase the accuracy of paleointensity determinations.

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