Deposit temperature of pyroclastic density currents emplaced during the El Chichón 1982 and Colima 1913 eruptions

<p>New data on the pyroclastic density current (PDC) deposit temperature (<em>T</em><sub>dep</sub>) are provided for two prominent eruptions of Mexican volcanoes of the twentieth century: the 1982 eruption of El Chichón and the 1913 eruption of Colima. In spite of similar lithofacies, magma composition and pre-eruptive conditions, the <em>T</em><sub>dep</sub> of the PDCs from the 1982 (El Chichón) and 1913 (Colima) eruptions differ significantly, with intervals of <em>T</em><sub>dep</sub> of 360–420 °C and 250–330 °C, respectively. These new data emphasize that a full understanding of the physical mechanisms responsible for equilibrium temperature attainment within a pyroclastic deposit has not yet been realized. The <em>T</em><sub>dep</sub> measured for El Chichón PDC deposits confirm the preliminary data published elsewhere, while Colima magnetic temperatures provide different values to those published previously. </p>