Geology. Козлова Е.П. - 31 стр.

      3.10 Сделайте письменный перевод текста (1200 п.зн. – 45 мин)

       Surveying – method of making relatively large-scale, accurate measurement of
the Earth’s surface. Surveying is divided into the categories of plane surveying and
geodetic surveying. Plane surveying concentrates on mapping relatively small areas,
where the curvature of the Earth is not a significant factor; the calculations of plane
trigonometry are sufficient. Geodetic surveying covers large areas of the globe, with
all attendant corrections for the curvature of the Earth; such surveying must be very
accurate, and geodetic instruments are precise.
       The history of surveying is very long. Before the 3 rd century BS the Chinese
possessed some form of magnetic compass. By the 2 nd century BS the Greeks used
the astrolabe, an instrument for measuring the altitudes of stars above the horizon.
The Romans acquired Egyptian surveying instruments, to which they added the water
level and the plane table. By the early 17 th century, the English mathematical
Edmund Gunter developed a Surveying Chain, which marked out standard measures
of distance. In the 1970s the metre - the basic unit for the metric system of
measurement - was established. It became the fundamental standard of length for
surveying.

     3.11 Прочтите и переведите текст 3B. Найдите в тексте ответы на
следующие вопросы:

   1) Why is air photography considered to be one of the advantageous methods of
     prospecting?
   2) What is the method of prospecting based on X–rays and ultrasonic transmission
      used for?
   3) What is the surveying of the earth’s resources from space based on?

                   Methods Applied in Mineral Prospecting

        Highly effective aerial methods of prospecting from aircraft and helicopter
have come into wide use. The use of air photographs allows the geologist to
determine conditions favorable for economic mineralization. Such conditions may
include the presence of faults and fracture zones, major igneous intrusions, dykes and
pegmatites. Geomorphological information from air photographs is also used in
mineral prospecting. For example, salt domes may be directly located on air
photographs. Advances in the development of colour films are likely to increase the
importance of this method (f. ex. copper districts may show large reddish areas near
the ore bodies).
        Recent developments deal with the application of more complicated remote
sensing systems to mineral exploration. Certain types of mineral deposits show strong
and unique fluorescent properties, which may be used in mineral exploration. The
possibility of using maser devices to excite spectral response in specific materials
(e.g. fluorescent mineral) has been suggested. Radar, having the capacity to penetrate

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