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rather younger.
Oil and gas fields, like people, come in all shapes and
sizes, some onshore, some offshore. In plan, they may be long
and narrow, or nearly circular; in section, they can be thick or
thin, deep or shallow. In size, they can be very large or rather
small-but they must all contain some minimum quantity of
recoverable oil or gas of marketable quality. This quantity may
be quite small near markets or near other fields, or rather large if
offshore at some distance from markets. There are very many
accumulations that are too small to become fields. Oil and gas
fields are commonly in trends (that are geological trends) or
groups of trends, and these collectively form petroleum
provinces.

TEXT №3.

1. Read the text.
2. Find the key sentence in each paragraph and translate it into
Ukrainian.

An oil or gas field begins as an anomaly on a map,
revealed by regional geological and geophysical surveys. The
anomaly is investigated with more detailed mapping, and if this
shows features that could trap petroleum, the company must
decide whether it is sufficiently promising to drill and if they can
obtain the finance to drill it (or seek partners). The drilling site is
chosen on the basis of a detailed seismic reflection survey. Such
is the precision of seismic surveys that there will be great
confidence in the geometry of the anomaly and in the general
nature of the sedimentary rocks in it, and, if there is some local
knowledge, also the ages of the rocks. There may even be direct
indications of gas (“bright spots,” “flat spots”), but the survey
will not generally provide any information on whether oil was
actually generated and came to accumulate there. That can only
be found out by drilling.
The first well drilled to a prospect is an exploration well,
sometimes called a wildcat. It is designed to acquire information,
not necessarily to produce what it finds on a permanent basis.