ORIGIN AND OCCURRENCE OF OIL
- Derived from decaying marine organic matters (usually zooplanktons and algae) trapped at seabed, compacted under high pressure and temperature which leads to formation of oil.
- Found only in variety of sedimentary rocks of various ages. (Mudstone, Shale, Sandstone, Limestone).
- Found in pore spaces of rocks and hence permeability and porosity of rocks drastically affect the availability of oil in that rock. (Sandstone>Shale)
- Whenever there is a cap rock (Nonporous rock) a sequence of gas, oil, water.
TRANSPORT OF OIL
- Oil is one of the few liquid commodities which can be transported in large quantities over long distances.
Different medium of transporting it:
- By road in oil trucks
- By rail in tank wagons
- By sea in oil tankers
- Even by aircraft for military or emergency purposes
IMPORTANCE OF PIPELINES FOR TRANSPORTING OIL
- Either to refineries or coastal shipping terminals
- Expensive to build and once built, their route is fixed and not easy to change.
- Therefore, before laying pipelines, it is important for oil companies to be sure there will be steady flow of oil through the line and a constant demand at the market end of the line.
- If the above condition is met, then pipelines are the most economical way of transporting inflammable liquid like oil.
- Where flexibility of routes essential to serve varied or fluctuating markets, or where pipelines insecure for political reasons, tanker transport by sea is more preferred.
- Crude oil pipeline, Product pipelines (Carrying refined)
- Natural gas is also carried to the destination.
- There are pumping stations along the pipelines which provide pressure to maintain the continuous flow.
Problems with pipelines:
- Each section will have to be brought to the location, welded carefully sealed.
- Underground if inhabited so that no effect on land use.
- Continuous maintenance. Corrosion.
- Leakage has to be monitored (Airplanes in uninhabited areas, trained dogs, ‘beat walkers’, tribals in Saudi and UAE who are paid well to guard the section)
- Political turmoil (can be destroyed by saboteurs from enemy nations)