Where can we find oil and natural gas?

Oil and natural gas are found in the small spaces between the grains in a sedimentary

rock.

Mathematically, porosity is the pore space in a rock divided by the total rock volume.

In good reservoirs the porosity is 10-30%.

Flow Direction

30% Porosity No Permeability

30% PorosityGood Permeability

Flow Direction

Porosity

Sand Grains

Microscopic Thin- Section of a sandstone

Porosity and Permeability

Flow Direction

= Open space in rock

Permeability

How do we find Oil and Natural Gas?Geologists and Engineers use reflection seismology to see if a rock has oil in it

Seismology trucks (thumper trucks) send sound waves through the earth and computers record how long it takes the waves to reflect back to receivers

The tires on a thumper truck are approximately 5 feet tall!

Seismic Lines

What are we looking for during seismic testing?

Anticline

Syncline

Geologic Structures

Anticlines are folds in which the oldest rock lies in the center or core and synclines have the youngest rock in its center or core.

Geologic Structures

Anticlines and Synclines form when rock layers are compressed, (pushed together) similar to carpet folds when its sides are pushed together. When rocks are compressed they can either bend, creating folds, or they can fracture, creating faults. Anticlines are sought out by geologists who explore for oil and gas because the arches form natural traps these hydrocarbons.

Structural Trap - Anticline

Upwarping of rocks (anticlinal folds) are particularly good at trapping crude oil and natural gas.

Structural Trap - Anticline

Oil formed in the source rock migrates upward through the reservoir rock until it is stopped by the cap rock.

OIL

How do we get it out of the ground once we’ve found it?

Drilling Rig

Drilling for Oil

Sometimes the oil reservoir is under a city, lake or other sensitive area.

Drilling for Oil

To reach oil reserves underneath the Oklahoma State Capitol Building, one oil well was directionally drilled from across the street.

Directional Drilling

To drill a directional well, the first part of the hole is drilled vertically. The hole kicks off, or deflects, so that the bottom of the well is hundreds of meters away from its starting point on the surface.

After drilling, sometimes a pumping unit is installed

Oil and Gas Production

A Christmas Tree is used to control the flow of oil and natural either to a storage tank or pipeline.

After the oil is pumped it is taken to an oil refinery

Refining Process

Oklahoma has five oil refineries. The refinery is where oil is heated until it separates into many different parts. These parts are then used to make products like gasoline, jet fuel heating fuel, tar and plastic

Crude OilNatural Gas

Uses of Crude Oil and Natural Gas