Wow, diving the cenotes WAS an experience. But note, I am finally writing about it about a month afterwards. A hazard, apparently, is contracting swimmer's ear, a bacterial infection contracted from stagnant waters. Whether it was the dives on Thursday, or the swimming on Friday at Ik Kil on the way to Chichen Itza, by the following Monday night, I felt the first symptoms. Hoping it would resolve, I did not go to the doctor until Wednesday. From there, two rounds of antibiotics, plus, on the second round, acetic acid drops, were necessary to put the infection to rest, finally, about a month later. Meanwhile I was deaf in my right ear much of the time. About a week after I got to the doctor, I got rear-ended on the way to work, and life has been a round of insurance forms and chiropractor visits ever since. Thus, I am only getting back to completing this blog six weeks after my return from Mexico.
First, a bit more about general impressions. The resort is very spacious. Partly, children are back in school, partly it's not high season, but mainly, with the cheap Mexican labor, the resort can provide a higher level of luxury than most US resorts. There are two phases, each with a very large pool with a swim-up bar. The tile work in the pool, and all over is magnificent. There are a couple phenomenal murals. In each phase there is also a lap pool and several hot tubs. The hottest, most humid period was when we were still experiencing the offshoots of the tropical storm. Later in the week, it was hot, but not so bad, and not so humid. Still, when I arrived and unpacked in my villa, I had to play with the controls a bit to get everything set right. Eventually I found that a combination of AC and the swamp cooler did the job - not too hot, not too cold. If you are not familiar with a swamp cooler, it is essentially a dehumidifier with a fan. When I spent a month in Melbourne, Australia, and arrived in January when it was still 110 degrees, even though I was staying in "executive housing," the only temperature control provided was a swamp cooler. The first couple weekends I spent lying in bed with the swamp cooler blowing over me! Here in the Yucatan, once I got the controls adjusted, I found I was emptying the 5 gallon water bin in the swamp cooler every 24 hours. That's for a 1300 square foot unit that has air conditioning as well. Do the calculations to figure out how humid it was. I think I got the humidity down to about 65%.
News note, November 14, 2010: This morning there was a large explosion at a hotel a mile or two north of where I stayed, the Grand Riviera Princess, killing 7 people. It was a natural gas explosion, and thoughts are that it could have been from a cooking stove, since the blast was near the hotel's restaurant, or it could have been from swamp gas that might have built up under the concrete pads. I definitely noted that the ecological setting of my resort was questionable. An extensive swampy area could be seen from the entrance to my villa behind the beach. The beach is an incredible white sand, but like many beautiful flat beaches, it has received much artificial enhancement to make it attractive. I believe the coastline of Playa del Carmen was a mangrove swamp before the resorts were developed. So it's not surprising that gases may be festering under the artificial concrete cover. One of the realities about Mexico. Construction is just not to US standards, and there is an inherent increased level of risk traveling there. Sad. Update November 27: they have ruled out swamp gas, but a poorly constructed cistern tank is a possibility, or a broken sewer line.
The Mexican government, often in partnership with foreign interests, has identified areas for development to attract tourists. In the 70's, as demand grew in Europe for tropical destinations, Mexico began to develop the Yucatan. Now the Yucatan coast is Mexico's largest tourist zone. Some people find going to such areas repellent. I do not care for the environmental devastation. On the other hand, tourism brings in much needed foreign income into Mexico. Besides people from the US, almost more Canadians visit, or winter in Mexico, and the Yucatan draws tourists from all over Europe and Central and South America.
The Royal Haciendas resort is the newest of six or seven developed by a Mexican-US partnership that developed one of the first resorts in Cancun. There's a nice story behind this partnership. Still I wouldn't buy here.
Geographically, the Yucatan is a fascinating area. The Yucatan Peninsula is located completely in the tropics, and it receives the same climate influences as mainland Mexico. Cuba, Grand Cayman and Jamaica are due East of Playa del Carmen. The main difference in the Yucatan Peninsula is the elevation. Most of the Yucatan is very flat and close to sea level. These lower elevations allow for warm days and temperate evenings all year long. You can think of the Peninsula as a big slab of limestone gently slanting into the sea. The farther south you go, the more likely you are to encounter low hills. By the same token, you must travel far offshore before you reach deep water. Limestone is soluble in water so the Yucatan's limestone bedrock is honeycombed with caves and sinkholes -- it's classic karst topography. Yucatan's sinkholes have a special name -- cenotes (seh-NO-tehs). Cenotes are the result of caves collapsing, forming holes in the ground with water in the bottoms of the holes. Because the limestone has so many holes in it, there are no major rivers throughout the entire Yucatan Peninsula. Water runs underground. Cenotes are very important in Yucatan history and present life. Because of the lack of rivers, the ancient Maya took their water from cenotes. Cenotes were important in the Maya religion, being the home of gods. Sometimes humans were thrown into cenotes as sacrifices. Today underwater archeological teams are discovering many Maya artifacts in cenotes.
THE LIMESTONE IS YOUNG, GEOLOGICALLY SPEAKING
Much of the outcropping limestone in the northern Yucatan is part of the Carrillo Puerto Formation of Miocene-Pliocene age. The Miocene and Pliocene are often considered as having occurred from 23.8 to 1.8 million years ago. Along much of the Yucatan coastline you find Quaternary deposits 1.8 million years old and younger.
THE CHICXULUB IMPACT CHANGED LIFE ON EARTH
About 65 million years ago a large asteroid or comet hit the part of the Earth that later would be occupied by the northwestern Yucatan Peninsula. The city of Mérida lies inside that zone. Today the impact zone is referred to as the Chicxulub Crater, though there is no crater or any other obvious evidence of the impact to be seen. The impact's crater is buried beneath 65 million years of sediment, much of which now has solidified to limestone. One reason the Chicxulub impact is of such interest is that it is thought to be responsible for the vast extinction of species that took place 65 million years ago. At that time dinosaurs were the Earth's most advanced form of life. The Chicxulub impact changed the Earth's weather conditions so drastically that all the dinosaurs died off. This enabled mammals to assume the dinosaur's dominant position. Had it not been for the Chicxulub impact, we humans may not have evolved as we did, or evolved at all.
The crater was discovered by Glen Penfield, a geophysicist who had been working in the Yucatán while looking for oil during the late 1970s. Penfield was initially unable to obtain evidence that the unique geological feature was in fact a crater, and gave up his search. Through contact with Alan Hildebrand, Penfield was able to obtain samples that suggested it was an impact feature. Evidence for the impact origin of the crater includes shocked quartz, a gravity anomaly, and tektites in surrounding areas.
The age of the rocks and isotope analysis show that this impact structure dates from the end of the Cretaceous Period, roughly 65 million years ago. The impact associated with the crater is implicated in causing the extinction of the dinosaurs as suggested by the K–T boundary, the geological boundary between the Cretaceous and Tertiary periods, although some critics argue that the impact was not the sole reason[4] and others debate whether there was a single impact or whether the Chicxulub impactor was one of several that may have struck the Earth at around the same time. Recent evidence suggests that the impactor may have been a piece of a much larger asteroid that broke up in a collision in distant space more than 160 million years ago.[5]
In March 2010, following extensive analysis of the available evidence covering 20 years' worth of data spanning the fields of palaeontology, geochemistry, climate modelling, geophysics and sedimentology, 41 international experts from 33 institutions reviewed available evidence and concluded that the impact at Chicxulub triggered the mass extinctions during K-T boundary including those of dinosaurs.[6][7]
The impact would have caused some of the largest megatsunamis in Earth's history, reaching thousands of feet high. A cloud of super-heated dust, ash and steam would have spread from the crater, as the impactor burrowed underground in less than a second.[26] Excavated material along with pieces of the impactor, ejected out of the atmosphere by the blast, would have been heated to incandescence upon re-entry, broiling the Earth's surface and possibly igniting global wildfires; meanwhile, colossal shock waves spawned global earthquakes and volcanic eruptions.[27] The emission of dust and particles could have covered the entire surface of the Earth for several years, possibly a decade, creating a harsh environment for living things. The shock production of carbon dioxide caused by the destruction of carbonate rocks would have led to a sudden greenhouse effect.[28] Over a longer period of time, sunlight would have been blocked from reaching the surface of the earth by the dust particles in the atmosphere, cooling the surface dramatically. Photosynthesis by plants would also have been interrupted, affecting the entire food chain.[29][30] There was however a quick recovery of plants only few months after the impacts. A model of the event developed by Lomax et al. (2001) showed that net primary productivity (NPP) rates would have increased to higher than pre-impact levels because of the high carbon dioxide concentrations, as growing leaves have a higher NPP than mature leaves.[31]
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