Chicxulub Crater and Ring of Cenotes

The topographic and geophysical features of the deep impact structure of the Chicxulub crater are reflected on the surface of the Yucatan Peninsula with an aligned arc of sinkholes, forming the “Ring of Cenotes”.

It has been known for almost 40 years that a large meteorite struck the Earth around 66 million years ago in a place in southern Mexico that we call Chicxulub, in the Yucatán Peninsula. It was about the same time that the large dinosaurs disappeared from the Earth. This was a most surprising discovery, since the meteorite crater is extremely well hidden under very thick 3,000 ft (1,000 m) of soft limestone rocks. However, we can see traces of the crater on the surface since there is a great number of very deep and large water filled sinkholes that are aligned along the edge of the crater basin. The local people call these sinkholes “cenotes” (pronounced say-no-tays) in a word tied to the Maya language (ts’ono’ot), meaning “a hole filled with water”.

How is it possible that the crater buried under thick layers of rock can manifest in some way on the surface?

All the cenotes that we know now were formed millions of years after the impact in a much more recent period, probably not more than 125,000 years, although it is known that they are related to the geometry of the buried crater.

There are several hypotheses * about the formation of the Cenotes Ring, all of which imply a relationship with the structures, faults and fractures that cross the Cenozoic carbonates, which is the upper layer of carbonates that was deposited covering the crater after the impact. However, there is no detailed explanation of the mechanisms that would operate to create the initial cavities and, more importantly, the mechanism by which the deep crater controls the flow of groundwater close to the surface has not been established either. Another non-tectonic hypothesis but which also implies a relationship with the impact is that which involves coral reefs (leaving more porous and soluble limestone) in the periphery of the “inner sea” (Cenozoic Basin / Cenozoic Basin) that was also formed as consequence of the impact, which does not have sufficient evidence.

* I recommend for people interested in this topic to review the information contained in the articles by Pope et al. (1993, 1996); Hildebrand et al. (nineteen ninety five); Perry et al. (1995) and Kinsland et al. (2000).

What is the mechanism responsible for transferring the geometry of the deep crater to the surface, through more than 1 km of Cenozoic carbonates?

Emiliano Monroy-Ríos