The Geology and Archaeology of Sinkholes

The Geology and Archaeology of Sinkholes A cenote (seh-NOH-tay) is the Maya term for a natural freshwater sinkhole, a geological feature found in the northern Yucatn Peninsula of Mexico, and other similar landscapes throughout the world. There are no rivers in the Yucatn; the regular high rainfall (1,300 mm or about 50 inches of rain falls every year) simply trickles through its calcareous landscape. Once below ground, the water forms a thin layer of water called a lens aquifer. Those aquifers flow horizontally, carving sinuous underground caves, and when the ceilings of those caves collapse, sinkhole openings to the surface are created. To be perfectly pedantic about it, the word cenote is a Spanish transliteration of the Maya word dzonoot or tsonot, which translates to water-filled cavity or natural well. Classifying Your Cenote Four general types of cenotes are defined in the geological literature: Open cenote or doline: a cylindrical shape with a large mouth and steep vertical walls (cenotes cilindricos in Spanish)Bottle-shaped or jug-shaped cenotes: a constricted mouth with a wider subsurface container (cenotes cntaro)Aguada-like cenotes: shallow water basins, typically degraded from a bottle or open cenotes (cenotes aguadas)Cavern cenotes: subterranean galleries with at least one cavity, access to which is a narrow opening that resembles a toads mouth (grutas) Uses of Cenotes As the only natural source of freshwater, cenotes are and were essential resources to people living in the Yucatn. Prehistorically, some cenotes were exclusively domestic, reserved for drinking water; others were exclusively sacred with their locations kept secret. A few, like the Great Cenote at Chichà ©n Itz, were sacred sites that served a number of religious purposes, including but not exclusively ritual sacrifice. To the ancient Maya, cenotes were passageways to the underground world of Xibalba. They were often also associated with the rain god Chaac, and sometimes said to be his dwelling place. Settlements grew up around many cenotes, and they were often part of or directly connected to the most important monumental architecture of the Maya capitals. Today cenotes are often fitted with an electric well, to allow people to easily draw water to the surface, which is then used for cultivation, agriculture or livestock. Field houses are built near them to support farming activities; shrines and masonry chapels are often found nearby. Some have developed complex water control features, tanks, and troughs. Alexander (2012) reports that cenotes are intimately tied to specific family groups, and often are the subject of ownership disputes over such issues as conservation and preservation. Yucatn Peninsula Cenotes Cenote formation in the Yucatn dates back several millions of years  when the Yucatn Peninsula was still below sea level. A prominent ring of cenotes results from the Chicxulub asteroid impact of 65 million years ago. The Chicxulub asteroid impact is often credited at least partly with killing off the dinosaurs. The impact crater is 180 kilometers (111 miles) in diameter and 30 meters (88 feet) deep, and along its outer limits is a ring of limestone karst deposits into which are eroded jug-shaped and vertical-walled cenotes. The Holbox-Xel-Ha fracture system in the northeastern coast of the Yucatn captures water from the east of the peninsula and feeding underground rivers and creating cavern and Aguada cenotes. Cenotes are still being created today: the most recent was July 2010, when a cave roof collapse in Campeche state created a 13 m (43 ft) wide, 40 m (131 ft) deep hole subsequently named el Hoyo de Chencoh. Non-Maya Cenotes Sinkholes are not exclusive to Mexico, of course, they are found throughout the world. Sinkholes are associated with legends on Malta (the legendary Maqluba collapse is thought to have occurred in the 14th century AD); and Lewis Carrolls Alice falling into Wonderland is thought to have been inspired by the sinkholes in Ripon, North Yorkshire. Sinkholes which are tourist attractions include North America:  Bottomless Lakes State Park and Bitter Lakes National Wildlife Refuge in New Mexico; Leon Sinks in Florida;  the submarine  Great Blue Hole  (Caribbean Sea);  Ik Kil  cenote in the Yucatan peninsula is a big draw to cliff divers.Europe: Lagunas de Canada del Hoyo (Spain), Modro Jezero (Red Lake) in Croatia;  and Il-Majjistral Nature and History Park in Malta.   Recent Cenote Research One is Rani Alexanders (2012) article about the changes in farming practices in the Yucatn during the historical period, including the changing roles of cenotes. Traci Ardrens paper on child sacrifice highlights the Maya mythology of the Great Cenote of Chichen Itza; Little Salt Spring (Clausen 1979) is a cenote in southwest Florida, where Paleoindian and Archaic use has been established. Charlotte de Hoogds MA on Chichen Itzas sacred well is worth a look. Some recent papers such as Munro and Zurita describe concerns about the worldwide protection and conservation efforts to counter increasing pressure from intensive tourist development, urban expansion and the non-indigenous use of the cenotes, particularly in the Yucatan, where pollution threatens to destroy the peninsulas only potable water source. Source: Alexander R. 2012. Prohibido Tocar Este Cenote: The Archaeological Basis for the Titles of Ebtun. International Journal of Historical Archaeology 16(1):1-24. doi: 10.1007/s10761-012-0167-0 Ardren T. 2011. Empowered Children in Classic Maya Sacrificial Rites. Childhood in the Past 4(1):133-145. doi: 10.1179/cip.2011.4.1.133 Chase AF, Lucero LJ, Scarborough VL, Chase DZ, Cobos R, Dunning NP, Fedick SL, Fialko V, Gunn JD, Hegmon M et al. 2014. 2 Tropical Landscapes and the Ancient Maya: Diversity in Time and Space. Archeological Papers of the American Anthropological Association 24(1):11-29. doi: 10.1111/apaa.12026 Clausen CJ, Cohen AD, Emiliani C, Holman JA, and Stipp JJ. 1979. Little Salt Spring, Florida: A unique underwater site. Science 203(4381):609-613. doi: 10.1126/science.203.4381.609 Cockrell B, Ruvalcaba Sil JL, and Ortiz Dà ­az E. 2014. For Whom the Bells Fall: Metals from the Cenote Sagrado, Chichà ©n Itz. Archaeometry:n/a-n/a. Coratza P, Galve J, Soldati M, and Tonelli C. 2012. Recognition and assessment of sinkholes as geosites: lessons from the Island of Gozo (Malta). Quaestiones Geographicae 31(1):25-35. de Hoogd C. 2013. Diving the Maya World: Reassessing old excavations with new techniques: a case study on the Sacred Cenote of Chichen Itza. Leiden: University of Leiden. Frontana-Uribe SC, and Solis-Weiss V. 2011. First records of polychaetous annelids from Cenote Aerolito (sinkhole and anchialine cave) in Cozumel Island, Mexico. Journal of Cave and Karst Studies 73(1):1-10. Lucero LJ, and Kinkella A. 2015. Pilgrimage to the Edge of the Watery Underworld: an Ancient Maya Water Temple at Cara Blanca, Belize. Cambridge Archaeological Journal 25(01):163-185. Munro PG, and Zurita MdLM. 2011. The Role of Cenotes in the Social History of Mexicos Yucatn Peninsula. Environment and History 17(4):583-612. doi: 10.3197/096734011x13150366551616 Wollwage L, Fedick S, Sedov S, and Solleiro-Rebolledo E. 2012. The Deposition and Chronology of Cenote T’isil: A Multiproxy Study of Human/Environment Interaction in the Northern Maya Lowlands of Southeast Mexico. Geoarchaeology 27(5):441-456.

Educational psychology Essays

Educational psychology Essays Educational psychology Essay Educational psychology Essay Appraisal is the procedure of roll uping. interpretation. and synthesizing information in order to do determinations about pupils ; supply scholars feedback about their advancement and their strengths and failings ; justice instructional effectivity and inform educational policy ( American Federation of Teachers. et Al. . 1990 as cited in Gage and Berliner. 1998 ) . On the other manus. motive is merely what moves scholars from ennui to involvement so that they continue larning. It arouses and directs learner’s activities towards larning over clip. Appraisals can actuate scholars if instructors and pupils functions are efficaciously performed. For case. the function of a instructor can be planing undertakings in a manner that scholars can finish with sensible sum of attempt. Difficult trials should be divided into subgroups that are accomplishable without inordinate attempt. The function of the instructor even includes ability to inform scholars in progress about the nature of the appraisals. In this manner. appraisals are able to actuate student’s attempt to larn. Furthermore. Nicholls ( 1999 ) as cited in Stepleton ( 2001 ) states appraisals will actuate scholars if they are non seen as a signifier of anguish to the pupils. The instructor should guarantee that pupils understand that appraisals are merely meant to help scholars towards accomplishment of effectual acquisition and attainment of educational ends. If pupils understand this. they will value appraisals and organize a positive attitude towards appraisals at that place by acquiring motivated to larn. Appraisals. if used judicially as in rating T trials and marking of Markss. can actuate scholars to larn ( Gage and Berliner. 1998 ) . Similarly. it is pointed out that given that scholars are labelled on the footing of appraisals and that these labels create outlooks about learner’s ability. features and educational competency. Teachers have to be careful in labelling pupils. Stepleton ( 2001 ) states that harmonizing to self-fulfilment prognostication theory. pupils learn to act in line with the label or feature that has been applied to them. Hence. if appraisals are to actuate pupils. instructors must avoid labelling scholars as hapless. dull. incompetent or failures on the footing of quantitative consequences of appraisals in the category. If a pupil feels the instructor knows him or her as an underachiever. the scholar may cleave to that outlook. On the other manus. good labels such as first-class. good and fantastic should be encouraged and used suitably to increase motive on the pupils larning attempts.

Discuss the challenges that global warming presents to both Essay - 1

Discuss the challenges that global warming presents to both governments and business - Essay Example These businesses include those reliant on fossil fuels in production or others that produce products that are the source of carbon emissions themselves. However, since everything comes at a cost, businesses are reluctant to combat the challenges that are bringing climate change. Climate change in general has affected businesses in all the industries regardless of their size. The primary reason for this assertion is the fact that the world is largely dependent on fossil fuels, the burning of which results in CO2 emissions, for its energy needs. Chief science adviser to Tony Blair, Sir David King believed that climate change has even greater threats than those posed by terrorism (Carey, 2004). The immediate reaction, as to what should we do in this regard, would be to develop alternatives for fossil fuels. What those alternatives are is then the challenge for businesses and governments to address. John Carey in his cover story for Bloomberg Business Week believes that the idea is to cu t down on usage of fossil fuels and to develop energy efficient vehicles and factories (Carey, 2004). The main contributor to greenhouse gas emissions however remains the energy sector. Surprisingly, and for the greater good, businesses adopting methods to address these concerns are thriving. Climate Group, an effort by companies and governments, helps to share stories of corporate success. Michael Northrop from the Climate Group says, "It's impossible to find a company that has acted and has not found benefits" (Carey, 2004). Although evidence exists of the energy sector benefitting from changes, the challenge exists in changing the dimensions of the industry to accommodate environmentally friendly substitutes to fossil fuels. Many companies are however reluctant to invest the appropriate amount of both time and money to find the most viable alternatives to fossil fuels. Oil companies have been primarily responsible for greenhouse gas emissions and have allegedly failed to restrict their contribution in the name of profit (Monteleone, pp. 144-154, 2007). Thus, it then poses a question to governments as to what should policy be aimed at. The answer is not that simple as even that comes at cost. Limits on pollution in the form tradable permits are being sought as a solution by the EU and the US in an attempt to curb greenhouse emissions. CEO of Xcel Energy Inc. Mr Wayne H. Brunetti says that one solution would be to give the companies the chance to figure out a solution and to allow them to set goals for 50 years down the road. He also stresses on the need for flexibility and the need for cooperation between institutions (Carey, 2004). The concerns of governments and environmental activists however are not restricted to the energy sector. Intel Corporation, the world’s largest chipmaker has been under scrutiny for its contribution to climate change. The challenge then again for businesses is to look for substitutes.  Intel’s Stephen Harper says that the search for alternatives is still on and they are planning to find solutions to the growing concerns about climate change (Carey, 2004). Surprising enough is the contribution of animal farms to the greenhouse process. The contributions made by the animal agricultural sector to greenhouse gas em