Thanks for your question.
“Tight gas” is some kind of a conventional reservoir that is characterized by very low permeability and porosity. So you need to fracture that conventional reservoir, because the reservoir is different from the source.... That's how we distinguish conventional from unconventional. So it's still a conventional reservoir, but with very low permeability, so in order to produce a gas out of it, you need to fracture that conventional reservoir, and it is called “tight gas”.