Transcript Offshore Oil, Formation, Types of Deposits, Rigs

Topic 2
Off-shore Oil
Sedimentary Basins of
Canada
(Locations of Oil and Gas)
1. Western Canada
Sedimentary Basin
2. Hudson Bay Basin
3. Mackenzie and Banks
Basins
4. Canadian Arctic Basin
5. Baffin Bay
6. Labrador Sea Shelves
7. Scotian Shelf
8. Grand Banks
9. Anticosti
10. Maritimes Basins.
How Oil Is Formed in the Ocean
• Millions of years  Bacterial action and  Oil reserves form
when non-porous rock
ago plants and
extreme pressure
animals of the
lies above porous
from
layers
of
oceans died &
sediment converted rock. Oil seeps up
settled on the
through the porous
the organic matter
ocean floor.
rock & is trapped by
to oil & gas.
the non-porous rock.
Oil Reserves
• Fold Trap: the up fold or anticline in the layers of
the earth's crust form the reservoir.
Oil Reserves
• Fault Trap: the vertical movement of the earth's
crust forms a v-shaped reservoir.
Oil Reserves
• Salt Dome Trap: The salt dome forms an up-fold in the
earth's crust not unlike the anticline caused by tectonic
forces.
Oil Reserves
• Stratigraphic trap: has a former limestone reef
as its porous rock feeding the reservoir.
Off-shore Oil Rigs
Modern Drill Rigs
 Submersible Rigs
 Jack-up Rigs
 Semi-submersible
Anchored rigs
 Semi-submersible
Dynamically
Positioned
Submersible Rigs
• Fixed columns ground them on the ocean
floor.
 Usually limited to ocean
depths of 20 m. For this
reason they are limited to
continental shelves,
relatively close to shore.
 The rigs are floated as
they are towed to drill site.
Once in position ballast
tanks are flooded until
columns rest on ocean
floor.
Submersible Rigs
Jack-Up Rigs
• Extendable legs ground them on the ocean floor.
 Are limited to a maximum
ocean depth of 100 m.
 The jack-up is similar to
the submersible in that it
rests on the ocean floor.
However its steel legs (Not
columns) rest on ocean
floor.
Jack-Up Rigs
Semi-Submersible Anchored Rigs
 Llimited to a max. ocean
depth of 200 m.
 Built on land, then flooded
and towed to the drill site.
Water is pumped in and out
of Ballast tanks to keep
stability along with anchor
lines.
 Oil is stored in pontoons
until shipped on-shore.
• Float BUT are
anchored above
the drill site.
Semi-Submersible Anchored Rigs
Semi-submersible Dynamically Positioned
• Use thrusters to keep position above the drill site.
 Able to drill outside the continental shelf. Still limited to a
max. ocean depth of 2000 m.
 Like other rigs they are towed to the
drill site. Water is pumped in and out
of Ballast tanks to help stability (NO
anchor lines).
 Like the Anchored rigs oil is stored
in pontoons until shipped on-shore.
 Note: dynamic means changing or
moving.
Semi-submersible Dynamically Positioned
• http://www.youtube.com/watch?v=w9Vj0jjd4ms
• http://www.youtube.com/watch?v=ZJzJDi7DInM&feature=related
• http://www.youtube.com/watch?v=lP9CpQS3TzY&feature=related
• http://www.youtube.com/watch?v=5KO9frLwwKQ&feature=related
• http://www.youtube.com/watch?v=3xlEUrfG7i8&feature=related
• http://www.youtube.com/watch?v=fl8L4qSqSqE&feature=related
• http://www.youtube.com/watch?v=Hy6M0II_I1A
• http://www.youtube.com/watch?v=xvPTcTDlpgQ&feature=related
• http://www.youtube.com/watch?v=KRibnvwkZF8
• http://www.youtube.com/watch?v=p6f60IUx87c&feature=related