A cenote (pronounced in Mexican Spanish [seˈnoˌte] and in English [səˈnəʊˌteɪ], plural: cenotes; from Yucatec Maya dzonot) is a type of sinkhole containing groundwater typically found in the Yucatán Peninsula and some nearby Caribbean islands. Mexican Spanish ( español mexicano in Spanish is the Spanish language as it is spoken in Mexico. English is a West Germanic language originating in England and is the First language for most people in the United Kingdom, the United States Yucatec Maya ("Maaya T'aan" in the revised Orthography of the Academia de Lenguas Mayas de Guatemala) is a Mayan language spoken in A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or Cenote, is a natural depression The Yucatán Peninsula, in Southeastern Mexico, separates the Caribbean Sea from the Gulf of Mexico. The Caribbean (ˌkærəˡbiən kæ'rəbiən Cariben|Caraïben or Caraïben; Caraïbe or more commonly Antilles; Caribe is a Region consisting The term is derived from a word used by the low-land Maya to refer to any location where groundwater is accessible.

Contents 1 Definition and description 2 Geology and hydrology 2.1 Formation 2.2 Penetration and extent 2.3 Freshwater/seawater interface 2.4 Types of cenotes 2.5 Association with the Chicxulub structure 3 Cenotes and the Maya 4 Cenotes and cave diving 5 Notable cenotes 5.1 Mexico 5.2 Canada 5.3 United States 6 References 7 External links

Definition and description

Cenotes are surface connections to subterranean water bodies ^[1]. While the most well-known cenotes are large open water pools measuring tens of metres in diameter, such as those at Chichén Itzá, the greatest number of cenotes are smaller sheltered sites and do not necessarily have any surface exposed water. Chichen Itza (tʃiːˈtʃɛn iːˈtsɑː from Chi'ch'èen Ìitsha' "At the mouth of the well of the Itza " is a The term cenote has also been used to describe similar karst features in other countries such as Cuba and Australia, in addition to the more generic term of sinkholes. Karst topography is a landscape shaped by the dissolution of a layer or layers of soluble Bedrock, usually Carbonate rock such as Limestone The Republic of Cuba (ˈkjuːbə or) consists of the island of Cuba (the largest and second-most populous island of the Greater Antilles) Isla de la For a topic outline on this subject see List of basic Australia topics. A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or Cenote, is a natural depression

Cenote water is often very clear, as the water comes from rain water infiltrating slowly through the ground, and therefore contains very little suspended particulate matter. The groundwater flow rate within a cenote may be very slow at velocities ranging from 1 to 1000 meters per year. In many cases, cenotes are areas where sections of cave roof have collapsed revealing an underlying cave system and the water flow rates here may be much faster: up to 10,000 meters per day^[2]. Cenotes around the world attract cave divers who have documented extensive flooded cave systems through them, some of which have been explored for lengths of 100 kilometers or more. Cave diving is a type of Technical diving in which specialized SCUBA equipment is used to enable the exploration of natural or artificial Caves which are

Geology and hydrology

Formation

Cenotes are formed by dissolution of rock which creates a subsurface void, which may or may not be linked to an active cave system, and the subsequent structural collapse of the rock ceiling above the void. Quintana Roo (kinˈtana ˈro is a state of Mexico, on the eastern part of the Yucatán Peninsula. The rock that falls into the water below will then be slowly removed by further dissolution, creating space for more collapse blocks. The rate of collapse increases during periods when the water table is below the ceiling of the void, since the rock ceiling is no longer buoyantly supported by the water in the void. Cenotes may be fully collapsed creating an open water pool, or partially collapsed with some portion of a rock overhang above the water. The stereotypical cenotes often resemble small circular ponds, measuring some tens of meters in diameter with sheer drops at the edges. A pond is a body of water smaller than a Lake, both being examples of Terrain features Although the term pond is universally used to describe waterbodies that Most cenotes however require some degree of stooping if not crawling to access the water.

Penetration and extent

In the north and north-west of the Yucatan Peninsula, the cenotes generally overlie vertically extensive voids penetrating 50 - 100 m below the modern water table. However, very few of these cenotes appear to be connected with horizontally extensive underground river systems, with water flow through them being more likely dominated by aquifer matrix and fracture flows. In contrast, the cenotes along the Caribbean coast of the Yucatan Peninsula (within the state of Quintana Roo) often provide access to extensive underwater cave systems, such as Ox Bel Ha, Sac Actun, Nohoch Nah Chich and Dos Ojos. Quintana Roo (kinˈtana ˈro is a state of Mexico, on the eastern part of the Yucatán Peninsula. Ox Bel Ha is a Cave system in Quintana Roo, Mexico. It is the longest known underground river and underwater cave in the world Sistema Sac Actun is an underwater cave system situated along the Caribbean coast of the Yucatan Peninsula with passages to the north and west of the village of Tulum Sistema Nohoch Nah Chich is an extensive water filled cave system connected with the Caribbean Sea via a coastal spring called Casa Cenote or Tankah Cenote and extending to approximately Dos Ojos is a flooded Cave system located north of Tulum, on the Caribbean coast of the Yucatan Peninsula, in the state of Quintana Roo,

Freshwater/seawater interface

The Yucatan Peninsula contains a vast density-stratified coastal aquifer where infiltrating meteoric water (i. Meteoric water is a Hydrologic term of long standing for water in the ground which originates from precipitation. e. , rainwater) floats on top of higher density saline water intruding from the coastal margins. The whole aquifer is therefore an anchialine system (i. An anchialine pool is a land locked body with a subterranean connection to the Ocean. e. , one that is land-locked, but connected to an ocean). Where a cenote, or the flooded cave it is an opening to, provides deep enough access into the aquifer then the interface between the fresh and saline water may be reached. The density interface between the fresh and saline waters is a halocline, which means a sharp change in salt concentration over a small change in depth. In Oceanography, a halocline is a strong vertical Salinity Gradient. Mixing of the fresh and saline water results in a blurry swirling effect due to refraction between the different density fresh and saline waters. The depth of the halocline is a function of several factors: climate and specifically how much meteoric water recharges the aquifer, hydraulic conductivity of the host rock, distribution and connectivity of existing cave systems and how effective these are at draining water to the coast, and the distance from the coast. In general, the halocline is deeper the further from the coast. In the Yucatan Peninsula this depth is 10 to 20 meters below the water table at the coast, and 50 to 100 meters below the water table in the middle of the peninsula, with saline water underlying the whole of the peninsula.

Types of cenotes

In 1936, a simple morphometry based classification system for cenotes was presented ^[3]. Cenotes-cántaro (Jug, or Pit cenotes) are those with a surface connection narrower than the diameter of the water body; Cenotes-cilíndricos (Cylinder cenotes) are those with strictly vertical walls; Cenotes-aguadas (Basin cenotes) are those with shallow water basins; and grutas (Cave cenotes) are those having a horizontal entrance with dry sections. The classification scheme was based on morphometric observations above the water table, and therefore incompletely reflects the processes by which the cenotes formed and the inherent hydrogeochemical relationship with the underlying flooded cave networks, which were only discovered in the 1980s and onwards with the initiation of cave diving exploration.

Association with the Chicxulub structure

Although cenotes are found widely throughout much of the Yucatan Peninsula, a ringlike arrangement of cenotes coincides with the theorized rim of the Chicxulub Crater. The Chicxulub Crater (tʃikʃuˈlub is an ancient Impact crater buried underneath the Yucatán Peninsula in Mexico. This crater structure, suggested by gravity mapping, may be the result of the meteorite that is theorized to be responsible for the K-T Boundary and the mass dinosaur extinction that occurred 65 million years ago known as the Cretaceous–Tertiary extinction event. The K-T boundary is a geological signature usually a thin band dated to 65 The Cretaceous–Tertiary extinction event, which occurred approximately ( Ma) was a large-scale mass extinction of animal and plant species in a geologically

Cenotes and the Maya

Cenotes have long been the principal sources of water in much of the Yucatán Peninsula. The Yucatán Peninsula, in Southeastern Mexico, separates the Caribbean Sea from the Gulf of Mexico. The region has almost no rivers and only a few lakes, and those often marshy. Cenotes are widely distributed, and supply better-quality water year-round. Major Maya settlements required access to adequate water supplies, and therefore cities, including the famous Chichén Itzá, were built around these natural wells. The Maya civilization is a Mesoamerican Civilization, noted for the only known fully developed written language of the Pre-Columbian Americas Chichen Itza (tʃiːˈtʃɛn iːˈtsɑː from Chi'ch'èen Ìitsha' "At the mouth of the well of the Itza " is a Some cenotes like the Cenote of Sacrifice in Chichén Itzá played an important role in Maya rites. Sacred Cenote (Well of Sacrifice is a noted Cenote at the Maya site of Chichen Itza. Believing that these pools were gateways to the afterlife, the Maya sometimes threw valuable items into them. AfterLife is a film drama set in Scotland directed by Alison Peebles made in 2003 about an ambitious Scottish journalist forced to choose between The discovery of golden sacrificial artifacts in some cenotes led to the archaeological exploration of most cenotes in the first part of the 20th century. In Archaeology, an artifact or artefact is any object made or modified by a human culture, and often one later recovered by some archaeological Archaeology, archeology, or archæology (from Greek grc ἀρχαιολογία archaiologia – grc ἀρχαῖος archaīos The twentieth century of the Common Era began on Edward Herbert Thompson, an American diplomat who had bought the Chichén Itzá site, began dredging the Sacred Cenote there in 1904. Edward Herbert Thompson ( 28 September, 1857 - 11 May, 1935) was a United States born Archaeologist and Diplomat Sacred Cenote (Well of Sacrifice is a noted Cenote at the Maya site of Chichen Itza. Year 1904 ( MCMIV) was a Leap year starting on Friday (link will display calendar of the Gregorian calendar (or a Leap year starting on He discovered human skeletons and sacrificial objects confirming a local legend, the Cult of the Cenote, involving human sacrifice to the rain gods (Chaacs) by ritual casting of victims and objects into the cenote. In Biology, the skeleton is a strong and often a rigid framework that supports the body of an animal holding it upright and giving it shape and strength (Also skeletal Human sacrifice is the act of Homicide (the Killing of one or several Human beings in the context of a Religious ritual ( ritual killing Chaac (also rendered as Chaak or Chac) is the originally Yucatec name of the Maya rain deity

Cenotes and cave diving

Cenotes have attracted cave divers and there are organised efforts to explore and map the underwater systems. Cave diving is a type of Technical diving in which specialized SCUBA equipment is used to enable the exploration of natural or artificial Caves which are The Quintana Roo Speleological Survey maintains a list of the longest and deepest water filled and dry caves within the state boundaries. The Quintana Roo Speleological Survey with the abbreviation QRSS is a special project of the National Speleological Society.

Notable cenotes

Mexico

Yucatan Peninsula:

• Dos Ojos, near Tulum, Mexico
• Dzibilchaltun, Yucatan, Mexico
• Sacred Cenote, Chichen Itza, Mexico
• Xtacunbilxunan, Bolonchen , Mexico

Central and Northern Region:

• Zacatón, Tamaulipas, Mexico

Canada

• Devil's Bath, northern Vancouver Island, Canada

United States

• Bottomless Lakes, near Roswell, New Mexico

References

External links

• Sistema Zacatón
• Volcanic karstification of Sistema Zacaton, Mexico (Gary, Sharp, 2006)
• Stages in the Formation of a Cenote
• Doline, Sinkhole, Cenote
• Cenotes of Chichén Itzá
• Quintana Roo Speleological Survey (QRSS)
• Year 1999 Cenotes Conference in Perugia, Italy
• Maps of Chicxulub and Ring of Cenotes

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