co-range lines
74
co-range lines connect the points in a tidal chart where the tide has the same
amplitude or tidal range (difference between high and low water level, or twice
the amplitude).
core (1) ~earth 's internal structure; (2) (oceanog.) vertical sample of the ocean bottom obtained with a corer. Cores are especially useful in studying stratification.
A variety of oceanographic coring devices exist to extract cores from the sea
bottom. ~bottom samplers, ~corer, ~core drill.
core drill drilling device that cuts a core from the drill hole. It is equipped with a
hollow, cylindrical cutting tool and two nested tubes above it. The outer tube
rotates with the drill and the inner tube receives and preserves a core from
the material penetrated.
corer ocean-bottom sampler that is a hollow cylinder or box (~box corer), lowered by cable and driven vertically in the sediment. After penetration, the
corer contains a core of the ocean bottom. Cylindrical corers vary in length
of less than a meter to tens of meters, while the diameter varies from about
2.5 cm to more than 15 cm. Gravity corer penetrates the ocean floor solely by
its own weight and velocity impact. It is less efficient than a piston corer,
which contains a piston inside the core tube. The piston remains on the
V\
V\
~ ' )
1
u l
1
-
I
;In
.i I:'
i f r<
Piston corer
74
co-range lines connect the points in a tidal chart where the tide has the same
amplitude or tidal range (difference between high and low water level, or twice
the amplitude).
core (1) ~earth 's internal structure; (2) (oceanog.) vertical sample of the ocean bottom obtained with a corer. Cores are especially useful in studying stratification.
A variety of oceanographic coring devices exist to extract cores from the sea
bottom. ~bottom samplers, ~corer, ~core drill.
core drill drilling device that cuts a core from the drill hole. It is equipped with a
hollow, cylindrical cutting tool and two nested tubes above it. The outer tube
rotates with the drill and the inner tube receives and preserves a core from
the material penetrated.
corer ocean-bottom sampler that is a hollow cylinder or box (~box corer), lowered by cable and driven vertically in the sediment. After penetration, the
corer contains a core of the ocean bottom. Cylindrical corers vary in length
of less than a meter to tens of meters, while the diameter varies from about
2.5 cm to more than 15 cm. Gravity corer penetrates the ocean floor solely by
its own weight and velocity impact. It is less efficient than a piston corer,
which contains a piston inside the core tube. The piston remains on the
V\
V\
~ ' )
1
u l
1
-
I
;In
.i I:'
i f r<
Piston corer