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sentence:

Migration as a separate phase in
water has the following merit:

a) it has no merits at all.
b) this state is found in the accumulation;
c) it turns into colloidal solution;
d) it turns into emulsion.

Варіант 4.

The accumulation of petroleum in a trap is accomplished
when the physical properties and geometry of the rocks prevent
further migration. Since petroleum is less dense than water, the
barrier to further migration is, in general, such that it prevents
upward, or an upward component of, migration.
The main forms of petroleum traps are well known: they
consist of the anticlinal trap, the fault trap, and the stratigraphic
trap (with which unconformity traps are classified in spite of the
fact that this is a structural term). The entrapment of petroleum in
anticlines was one of the first principles of petroleum geology, and
it has dominated petroleum-geological thinking. Its essential
features are: a) a geometrical closure, that is, the structural
contours on top of the reservoir form closed rings; b) a reservoir
rock that has permeability (which implies porosity); and c) a fine-
grained, relatively impermeable cap rock that overlies the reservoir
and seals it.
One must be specific and state that the closure must be on
top of the reservoir rock and under the cap rock because there are
many anticlines in which the geometry of the individual rock units
changes with depth.

І. Choosing the Correct Definition for a Context:

st
According to the 1 passage the accumulation of
petroleum in a trap is accomplished when:

a) when petroleum can move further;