Geology. Козлова Е.П. - 53 стр.

13) Lord Kelvin’s calculation was based on the assumption that the earth was molten
at its time of origin and has been cooling ever since.

Modal Verbs
1)A substance may respond elastically to a rapid stress but may be deformed
viscously by a stress applied over a long period of time.
2) Many features of the mid-ocean ridges can be explained by convection currents.
3) Life could have formed only in an oxygen-free environment.
4) A great deal of attention had to be paid to the exact design.
5) A program may consist of three instructions depending on the complexity of the
task.
6) The equipment can be used to measure the solubilities of minerals in aqueous
solutions up to 300 0 C.
7) It is to be expected that rocks will be ductile in nature under pressures and
temperatures at which they would be brittle in ordinary laboratory tests.
1) It is evident that geology can be approached from several sides.
9) More research must be done before people will know for sure.
10) The student of Geological Department must know all the latest achievements of
science and engineering.
11) The weight of rock would supply enough pressure to lift magma.
12) This heat can be converted into other forms.
13) The colour, shape and size of any given mineral may vary greatly.
14) The earth’s heat may be a remnant of its formation, or may be due to radioactive
sources in the earth.
15) No one had been able to predict whether quarts could be deformed plastically or
not.

The Participle I

1) As time goes on, the proportion of coal coming from thick seams, where working
is easy and cheap, tends to decline.
2) Of all the hard minerals currently being exploited on the continental shelf, sand
and gravel are by far the largest in terms of both volume and value.
3) The professor told the students about the experiments now being carried on in the
laboratory.
4) This comparison shows the importance of using this method for accurately
calculating porosity in gas zones.
5) The nature of the sea floor is determined by four controlling factors.
6) The deposit can be worked with existing technology.
7) Designing new mining machines, engineers pay attention to geological condition
in the mines.
8) Exploration by boring provides data and information relating to the existence of
coal seams and the intervening data.
9) Geology is concerned with the processes operating in the earth.

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