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(про послідовне залягання пластів)
resume – продовжуватись, тривати renewed sedimentation – поновлене осідання
angular - кутовий tilted - нахилений
folded – зігнутий disconformities – паралельне неузгоджене
напластування (залягання пластів); ерозійна
стратиграфічна паралельна неузгодженість
(напластування)
nonconformity – стратиграфічне inclusions – включення (домішки) в мінералі
неузгодження у напластуванні
principle of cross-cutting relationships –
принцип наскрізного розташування
cease – зупинятись, припинятись

Task 2. Read the text, translate it into Ukrainian.

Text 1

Relative Dating—Key Principles
The geologists who developed the geologic time scale revolutionized the way people
think about time and perceive our planet. They learned that Earth is much older than anyone had
previously imagined and that its surface and interior have been changed over and over again by
the same geological processes that operate today.
During the late 1800s and early 1900s, various attempts were made to determine Earth’s
age. Although some of the methods appeared promising at the time, none proved to be reliable.
What these scientists were seeking was a numerical date. Such dates specify the actual number
of years that have passed since an event occurred. Today our understanding of radioactivity
allows us to accurately determine numerical dates for rocks that represent important events in
Earth’s distant past. Prior to the discovery of radioactivity, geologists had no accurate and
dependable method of numerical dating and had to rely solely on relative dating.
Relative dating means placing rocks in their proper sequence of formation, first, second,
third, and so on. Relative dating cannot tell us how long ago something took place, only that it
followed one event and preceded another. The relative dating techniques that were developed are
valuable and still widely used. Numerical dating methods did not replace these techniques; they
simply supplemented them. To establish a relative time scale, a few basic principles or rules had
to be discovered and applied. Although they may seem obvious to us today, they were major
breakthroughs in thinking at the time, and their discovery and acceptance was an important
scientific achievement.
Nicolaus Steno, a Danish anatomist, geologist, and priest (1636–1686), is credited with
being the first to recognize a sequence of historical events in an outcrop of sedimentary rock
layers. Working in the mountains of western Italy, Steno applied a very simple rule that has
come to be the most basic principle of relative dating—the law of superposition. The law simply
states that in an undeformed sequence of sedimentary rocks, each bed is older than the one above
it and younger than the one below. Although it may seem obvious that a rock layer could not be
deposited unless it had something older beneath it for support, it was not until 1669 that Steno
clearly stated the principle.
Steno is also credited with recognizing the importance of another basic principle, called
the principle of original horizontality. Simply stated, it means that layers of sediment are
generally deposited in a horizontal position. Thus, if we observe rock layers that are flat, it
means they have not been disturbed and they still have their original horizontality. However, if
they are folded or inclined at a steep angle, they must have been moved into that position by
crustal disturbances sometime after their deposition.