If it costs $5m to sink a well that only ever returns $1.2m NPV return then you could have 1000tcf and it is not commercial.
For comparison - half of the worlds total oil-in-place is locked up as shale oil - around 300 billion barrels estimate (likely much more) in the US alone - but it is not viable to produce so it is worthless.
I suggest you do your own analysis. You shouldn't trust anyone's analysis but your own. My numbers were literally just back-of-the-envelope numbers. Don't trust broker reports - the self-interest embedded in most of them is so strong you need armour piercing bullets to cut through the cr@p.
GDN Price at posting:
10.0¢ Sentiment: Sell Disclosure: Not Held