Field of science concerned with origin of planet Earth, its
history, its shape, materials forming it, and processes that
are acting and have acted on it.
Fourth division of Tertiary period
spanning a time interval from 26 to 12 million years ago.
Oligocene
Third division of Tertiary period
spanning an interval from about 40 to 25 million years ago.
Pay Zone
Stratum of rock in which hydrocarbons are found.
Permeable
Cracks and pore spaces between the rock particles (such as
porous sandstone or fractured limestone) are interconnected and
are large enough to permit fluid movement.
Permian
Period of geological time about 285 - 248 million years ago.
Plate
Tectonics
Earth's solid crust is broken up into about a dozen semi-rigid
plates, boundaries of which are zones of tectonic activity.
Play
Group of fields with similar
trap structures / reservoir
rock.
Pleistocene
Division of Quaternary period,
also known as Ice Age.
Pliocene
Fifth and most recent division of Tertiary
period on geologic time scale from about 12 million to 2 million
years ago.
Precambrian
Rocks older than 600 million years. Earliest division of
time for which rock strata are recognised.
Quaternary
Period of geological time about 1.64 million years ago.
Seal or Cap
Rocks (salt, clays or cemented sandstone) in right shapes
and relative positions
to form traps.
Sedimentary
rock
Formed by consolidation of deposits formed by settlement
of sand, silt, and
other materials.
Source rocks
Rocks containing sufficient organic substances to generate
hydrocarbons.
Stratigraphic
traps
Originate where suitable combination of rock types is deposited
in a particular environment.
Structural
traps
Formed by Earth movements that fold rocks into suitable shapes
or juxtapose reservoir and
sealing rocks along faults. Traps may also form when rocks are
domed over rising salt masses.
Subsalt
Refers to rock formations lying beneath long, horizontal
layers of salt. These rock formations may contain hydrocarbons.
Tertiary
Period of geological time about 65 - 1.64 million years ago.