Tight gas is unconventional natural gas

Natural gas

Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...

 which is difficult to access because of the nature of the rock and sand surrounding the deposit. Because this gas is so much more difficult to extract than natural gas from other sources, hydraulic fracturing

Hydraulic fracturing

Considerable controversy surrounds the current implementation of hydraulic fracturing technology in the United States. Hydraulic fracturing, or fracking, is the process of utilizing pressurized water, or some other liquid, to fracture rock layers and release petroleum, natural gas, or other...

 and directional drilling

Directional drilling

Directional drilling is the practice of drilling non-vertical wells. It can be broken down into three main groups: Oilfield Directional Drilling, Utility Installation Directional Drilling Directional drilling (or slant drilling) is the practice of drilling non-vertical wells. It can be broken down...

 is necessary to produce the well.

With permeability of the rock as little as one nanodarcy

Darcy

A darcy and millidarcy are units of permeability, named after Henry Darcy. They are not SI units, but they are widely used in petroleum engineering and geology. Like other measures of permeability, a darcy has the same units as area.-Definition:Permeability measures the ability of fluids to...

, reservoir simulation

Reservoir simulation

Reservoir simulation is an area of reservoir engineering in which computer models are used to predict the flow of fluids through porous media.-Uses:...

becomes important to optimize the spacing and completion of staged fractures to maximize yield with respect to cost.