Connectivity in a Karst System Using Electrical Resistivity Tomography and Network Theory

Abstract

The Ring of Cenotes (RC) is an alignment of numerous cenotes (sinkholes) in a semicircular form (with a radius of 100 km) located in northwestern Yucatán, México. The formation roughly coincides with a concentric ring that corresponds to a buried structure, which has been identified as the product of a meteor impact, known as the Chicxulub crater. Secondary permeability generated by the fracturing and faulting of the sedimentary sequence in the Chicxulub crater has favored the karstification process and therefore the development of underground rivers that transport water from the mainland to the sea. This study implements the network theory to study the hydrological connectivity between a group of 11 cenotes within the RC. Eight electrical resistivity tomography transects were used as an empirical basis. Each transect was acquired directly in the field using the SuperSting R1/IP equipment with a dipole-dipole configuration. An adapted version of the reliability algorithm for communication networks was used as a theoretical model. We found evidence of the existence of water cavities in the study area. We made a network from the data and assigned connection probabilities among cenotes as a function of the separation length and the number of water cavities, as well as their size.

Insights into the Chemical Diversity of Selected Fungi from the Tza Itzá Cenote of the Yucatan Peninsula

“… 1 The origin of cenotes is related to the impact of the Chicxulub asteroid around 66 millions of years ago, which caused changes in the karst features. 2 , 3 These habitats are physically and chemically unique due to the phototrophic activity of its microbial communities. In particular, the carbon and sulfur cycles completed by different microbes affect the sulfate reduction into aqueous sulfide, accelerating the limestone dissolution, and increasing alkalinity.…”

“…One of the most famous geological features in the Yucatan peninsula is the ring of cenotes (from the Maya word ts’onot ), which is a group of sinkholes formed by the process of karstification . The origin of cenotes is related to the impact of the Chicxulub asteroid around 66 millions of years ago, which caused changes in the karst features. , These habitats are physically and chemically unique due to the phototrophic activity of its microbial communities. In particular, the carbon and sulfur cycles completed by different microbes affect the sulfate reduction into aqueous sulfide, accelerating the limestone dissolution, and increasing alkalinity. , In addition, most of the cenotes have hydraulic connections or networks across the region, and the microbial communities, especially freshwater fungi and bacteria, play a key role in keeping the balance of the entire ecosystem …”