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托福听力背景知识小课堂(1)

2018-01-10 13:38:52 来源:江博教育 作者:孙莹老师

 托福听力的几大学科场景是最让同学们崩溃的了,在考场上,听到自己熟悉的场景和完全没有接触过的内容完全是两种不同的体验有木有。

 

今天,我们来看看 Dating Methods in Archaeology,是不是看到 dating method就已经很慌张了,那到底啥是Dating Methods in Archaeology,字面理解就是“考古年代的测定”。这下好理解了,那如何来进行考古年代的测定呢?  

 

    一般有两种情况:Absolute dating和Relative dating。如何区分质量中测量手段?Absolute dating指的是诸如Radiometric Dating的年代测定手段。一般来说是利用放射性同位素衰变的手段,用以确定原先存活的动物和植物年龄,用这种方法甚至可以测定至万年前的时代。对于考古学来讲,这是一个相对准确的测年法技术。

Relative dating指的是通过一些间接的考古学证据来推测检测物年代的方法。比如,商周时期遗迹中出土的文物,理论上来讲应该诞生于商周时期(或更早)。附上一篇文章:

Dating Methods in Archaeology      

If there is one fundamental issue on which most archaeologists can generally agree, it is the importance of chronology in studying the past. Although one of the most important contributions that archaeology can make is the study of cultures over long time spans, control of the time dimension is crucial in almost all kinds of archaeological research. In studying the archaeological record, the archaeologist needs to differentiate those materials that are contemporary and those that reflect the passage of time. Given the importance of establishing the temporal relationships of archaeological remains, it is not surprising that until the introduction of dating techniques from the physical sciences (e.g., chemistry and nuclear physics), issues of chronology dominated archaeology. Archaeologists can now access a wide variety of techniques to estimate the age of archaeological remains, and can now turn their attention to issues other than chronology.

The dating methods used by archaeologists vary considerably in precision and the nature of the material actually dated. Age determinations for archaeological materials may be direct or indirect. Direct dates are derived from the actual artifact, feature or ecofact to determine the age of the material. Indirect dates are based on material associated with the archaeological item of interest. For example, ash in an ancient hearth can be dated by the radiocarbon dating method (discussed below) and other material, such as pottery, stone tools, and fragments of animal bone associated with the hearth, can then be indirectly assigned the same age. This assignment, however, assumes that there is sufficient evidence indicating that both the hearth and the artifacts reflect the same contemporaneous event, thus allowing the extension of the direct date to the other related material. Dates may be relative or absolute in their scale of measurement. Relative dating simply orders remains into a ranked chronological sequence, where the age of each is relative (i.e., earlier than later than, or contemporary) to the others. The preliminary steps in most archaeological research usually employ relative dating methods to order artifacts, features and sites into temporal sequences. Absolute dating provides a specific calendar age estimate (e.g., 1000 years ago), thus allowing determination of the actual amount of time difference between absolute dates. Although absolute dates provide a calendar age, they vary in their precision, as many have an uncertainty factor attached that indicates a range of time rather than a specific date.

Although dating methods are used to determine the age of objects and events, these dates are ordered to establish a chronology that provides a temporal framework in which the archaeological material can be placed. This chronology-building process is the foundation for archaeological studies. In this chapter, we examine some of the major techniques that have been developed to date the archaeological past and material from the archaeological record.


相信有了一定的知识基础,一定可以让你高速备托福。

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