[1][2][3] It is located primarily in the Mexican state of Chiapas, but outcrops lie as far west as Petén, Guatemala.

The most prominent exposures are at the División del Norte and Belisario Domínguez quarries near Palenque, Chiapas, which contain articulated fish skeletons belonging to a variety of taxa of both Cenozoic and Mesozoic affinities.

[4] The Tenejapa-Lacandón Formation is, temporally and geographically, the "closest" geological formation to the Chicxulub impact crater; it is located only 500 kilometres (310 mi) from the Chicxulub crater and was deposited approximately 3 million years after the impact.

For this reason, it is important evidence for understanding the recovery of ocean ecosystems in the wake of the Cretaceous-Paleogene extinction event, especially near the Chicxulub crater.

[1][5] The high number of well-preserved fossil fish specimens, likely relating to mass mortality events, makes it a lagerstätte.