Scientific Methods for Accurate Dating in Archaeology

Scientific Methods for Accurate date in archaeologyExplain the wideness of the following geological geological date method actings (a) communicate carbon dating, (b) kilobyte argon dating, (c) seriation, (d) stratigraphy.Archaeology can be define as the scientific study of the human knightly, of ancient human behaviour, from the earliest times right up to the present.(Fagan, 2006) .The study of archaeology as an academic discipline is dependant on the accuracy of various dating methods. Dating methods in archaeology can be divided into two groups Relative dating methods and inviol adequate dating methods. Although the splendour of the different dating methods may outweigh each other, the all argon rattling important to the study of archaeology as a whole. This essay shall focus on the importance of radio carbon dating, potassium argon dating, seriation and stratigraphy to the archaeological study.Accurate dating has always been of importance to scientist and archaeologis t alike. In archaeology dating can be categorised into relative dating and infrangible dating techniques. In moving forward explain the importance of radio carbon dating, potassium argon dating, seriation and stratigraphy to the archaeological study, superstar must first understand the difference between relative dating and absolute dating in archaeology. Relative dating in archaeology assumes the age of an artifact in relation and by similarity to other objects found in its environs. The bolt of the artifact and its archaeological location stratigraphically are required to flummox at a relative date. The limit to relative dating is that it cannot provide an ideal year or a specific date of use. Absolute dating on the other hand is the method of determine an approximate calculated age of an artifact in archaeology. The goal of archaeologist is ultimately to know how experienced sequences, sites and artefacts are in calendar years. To accomplish this absolute dating methods are used. From traditional historical methods to those which are based on the great variety of modern scientific techniques currently available. As compared to relative dating which only provides an order of events, absolute dating presents archaeologists with a more calculated evaluation of the objects age.The first area of discussion in understanding the different dating techniques in archaeology would be stratigraphy. According to Renfrew and Bahn, stratigraphy is the study of stratification- the laying down or depositing of strata one above the other. (Renfrew and Bahn 2008, 122). This basically involves ordering things into sequences. A succession of layers should provide a relative chronological sequence from the earliest (the bottom layer) to the latest (top), as seen in figure one. Its important to note that stratigraphy involves the Law of Superposition. Fagan describes the Law of Superposition as, the notion that key levels are earlier than those that cover them. (Fagan 2009 , 103). He further explains that the lower levels are relatively earlier than the by and by strata, which is basically entails. Scientific archaeologists grasped at this rather quickly, although it wasnt used as a consistent technique until most the turn of the 19th century. Since then, the technique has been refined, and tools such as theHarris Matrixassist in picking out the sometimes quite an complicated and delicate deposits. The study of stratigraphy on archaeological sites was used in North America and Mesopotamia. The importance of stratigraphy is good and well provided it still does not provide an accurate form of dating, it all involves speculation. This is since as a downfall since archaeological research strives in the most accurate form of understanding of the past societies and cultures. Figure1Title Stratification exampleSource pages.vassar.eduThe other archaeological dating method to be discussed is seriation. Seriation is a truly common form of archaeological i nterpretation. Seriation is a form of relative dating technique. With the assumption that artefacts changed with passing(a) time in radical ways, archaeologist use seriation techniques to place artefacts in chronological order. Seriation is the changing of style of an object over time. Renfrew and Bahn explain that there are two versions of the seriation technique contextual seriation and frequency seriation. contextual seriation, also called sequenced dating is where artefacts are arranged according to the frequencies of their co- occurrence in specific context. In the nineteenth century Sir Flinders Petrie was the founding father of this type of seriation. He used this method to establish order in large Egyptian graves. Frequency seriation on the other hand, was established by an American archaeologist at a Mayan site in Yucatan 1940. The principle of frequency seriation relies predominantly on measuring changes in the proportional abundance, or frequency of a ceramic style. W.S. Robinson and G.W. Brainerd in their paper published in American ancientness in 1951 hypostasised two statements about frequency seriation. First, the assumed that pottery styles gradually become more familiar, cave in peak of popularity, and then fade away. Secondly, they argued that a given time period, a pot style popular at one site would similarly be popular at another.(Renfrew and Bahn 2008, 128). Archaeologist such as James A. Ford working in American Southeast and Frank Hole in Iran were able to establish chronological stiffness using this method. Nevertheless it should always be borne in mind that seriation by itself does not tell us which end of a given sequence is first and which last- the true chronology has to be determined by other means.(Renfrew and Bahn 2008, 128).Figure2Title Seriation of PotterySource http//anthro.palomar.edu/time/glossary.htmThe next dating method to be discussed is potassium argon dating. This is a type of absolute dating technique. This meth od is used in the first place to date rocks thousands of years old. Geologists use this method to date rocks as early as four to louver billion years old and as recent as 100,000 years old before present. (Fagan 2009, 119). The acress crust is engulfed with potassium and as a result it is present in almost every mineral. Potassium argon dating is based on the principle of radio active decomposition, the steady but very slow decay of hot isotope potassium -40 (40K) to the inert gas argon-40 (40Ar) in volcanic rock. intimate the decay rate of 40K-its half(a) life is around 1.3 billion years- a measure of the quality of 40 Ar trapped within a 10g rock sample gives and estimate of the date of the rocks formation. The major limitations of the technique are that it can only be used to date sites buried by volcanic rock, and an accuracy of +10 percent is rarely achieved. However, potassium argon dating played a crucial role in the site Olduvai Gorge in Tanzania. The site in East Afr ica was the home of the study of human evolution, as it yielded fossil remains of Australopithecus, Homo habilis, and Homo erectus, as well as large numbers of stone artifacts and bones. It should be historied that the Rift Valley in Olduvai is a volcanic area, and its two million year old chronology has been established by potassium argon dating of the relevant deposits of harden volcanic ash and other materials.The final archaeological dating method to be discussed is the absolute dating technique radio carbon dating. Radio carbon dating has a major carry on on archaeology, in particular on pre history since the lack of a written record leaves oft to conjecture. Radio carbon has transformed our understanding of the past. According to Bowman the materials which can be dated by radio carbon are those which once formed part of the biosphere and are therefore organic. For example, the most normally preserved sample types occurring on British sites are bones, shells and charcoal. (B owman 1990, 12). The pioneer for radio carbon dating is the American chemist Willard Libby, who in 1949 published the first radio carbon dates. Libby had been one of the scientists during World War II who was studying cosmic radiation, the sub- atomic particles that constantly bombarded the earth, producing high- energy neutrons. These neutrons react with nitrogen atoms in the atmosphere to stick atoms of carbon-14 (14C), or radio carbon, which are unstable because they have eightsome neutrons in the nucleus because they have eight neutrons in the nucleus instead of the usual six as for ordinary carbon (12C). This availability leads to radioactive decay of 14C at a regular rate. Libby estimated that it took 5568 years of half of the 14C in any sample to decay its half life although modern research indicates that more accurate figure is 5730 years. (Renfrew and Bahn 2008, 142).Libby analyzed that the decay of carbon 14 at a constant rate should be balanced by its constant product ion by dint of cosmic radiation and therefore the proportion of 14C in the atmosphere should remain the same throughout time. However, Libbys about the level of 14C in the atmosphere has varied some what, since the radio carbon dates obtained from tree- rings see that before about 1000BC, trees were exposed to greater concentrations of atmospheric 14C than they are today. At this point it should be noted that this radio carbon method can be used anywhere, no matter the climate, as yen as there is material or organic origin. This is different as compared to the other absolute dating technique discussed above potassium argon which is only limited to dating volcanic rocks. During the latter half of the twentieth century, certain advancements had been made to help correct the limitations of radiocarbon dating. For instance the accelerator mass spectrum analysis (AMS) method is becoming the dominant method used in radiocarbon dating. This requires smaller samples still. AMS counts th e atoms of 14C directly, disregarding their radioactivity. The stripped-down sample size is reduced to as such little as 5-10mg, thus enabling preciously organic materials such as the Turin shroud , to be sampled and directly dated, and making feasible the direct dating of pollen. Primarily, it was hoped that the dateable time span for radiocarbon using AMS could be pushed back from 50,000 to 80,000 years, although this is proving difficult to achieve in part because of sample contami farming. (Thomas 1999, 76). It should be noted that for inorganic materials, thermoluminesence and other new dating techniques are useful.As compared to the other dating techniques as discussed above, radiocarbon dating can be seen as the most accurate and important to archaeologist in putting together the past. It was used to date Upper Paleolithic paintings in the Chauvet Cave, southern France. However all results over 30,000 BP are subjected to problems. Radiocarbon was also used to assert to vali dity of the chronology of Europe. In the Caribbean, overseas radio carbon dating techniques are also used, in particular Trinidad. The nations parliamentary building currently is undergoing excavations, and the materials they find are shipped overseas for accurate dating using radiocarbon because Trinidad does not have the proper equipment for dating it, since radiocarbon equipment maybe some what expensive for a development nation to endure.In conclusion it can be said that radio carbon dating, potassium argon, seriation and stratigraphy are important dating techniques one way or the other. Although radiocarbon can be seen as the most efficient because of it accuracy and how far back it can date, the other dating techniques are very much relevantBIBLIOGRAPHYBOOKSBowman Sheridan, Interpreting the Past. Radiocarbon Dating. Los Angeles University of California Press, 1990, Print.Courbin Paul, What is Archaeology? An essay on the spirit of Archaeological Research. United States of Ame rica The University of Chicago Press, 1988. PrintFagan Brian, Archaeology. A Brief Introduction. New Jersey Pearson Education, 2006, Print.Renfrew Colin and Bahn Paul, Archaeology Theories, Methods, and Practice. United States of America Thames and Hudson Ltd, 2008, Print.Thomas Hurst David, Archaeology Down to Earth. United States of America Harcourt Brace College Publishers, 1999, Print.WEBSITES Swaminathan, Nikhil. Nondestructive Radiocarbon Dating College Station, Texas. Archaeology Archive. A publication of the Archaeological Institute of America, accessed October 30th 2014. http//archive.archaeology.org/1101/topten/texas.html.