Late Cretaceous to Eocene denudation history of the Tolimán area, southern Sierra Madre Oriental, central Mexico

This study presents the first apatite fission-track results from the Tolimán area, which is located in the western portion of the southern Sierra Madre Oriental, central Mexico. In total, six rock samples from different lithostratigraphic units were dated, adding new results to the thermochronological data set of the Sierra de los Cuarzos–San Joaquín–Tamazunchale transect in the Mexican fold-and-thrust belt. The apatite fission-track ages vary from 84 ± 4 Ma to 52 ± 2 Ma, indicating that the main denudation period of the Tolimán area lasted until the Eocene. Combining our results with previous geological data, we suggest that the western part of the southern Sierra Madre Oriental was uplifted and undergoing erosion during the whole period of development of the Campanian–Ypresian Mexican orogenic system. Therefore, the Tolimán area may be considered as one of the source areas from which clastic materials of the Campanian–Maastrichtian Méndez and Paleocene–Eocene Velasco and Chicontepec Formations were partially derived. Older cooling ages recording the latest Aptian accretion of the Guerrero terrane with the Mexican continental interior were not detected in samples from the Tolimán area.