hy update out, page-15

-> I just listened to a live hearing of today's ND hearing docket on a
case for Continental Resources that is of interest to me.

When testifying to the economics, the Continental representative said
each Bakken and Three Forks well would have an IP of 430 barrels a day
with a 99% decline rate. He went on to testify to the remainder of
the economics, making it sound very profitable to Continental. They
are asking for up to seven additional wells.

What do you think he meant by a 99% decline rate?!

99% decline from 430 IP would leave 5 barrels a day?? Hardly
economically profitable. I must be missing something.


- > 20+ years out, wells will have declined that much.


- > that 99% decline rate is an annualized instantaneous decline rate.
many bakken wells experience a 100% annualized instantaneous decline
rate (carried out to four decimal places).

a 430 bopd well declining at a 99% annual decline rate would decline
to 292 bopd in one month.

the decline rate we are used to hearing about is the 'effective'
decline rate - the change in rate divided by the initial rate.
for the 430 bopd to 292 bopd in one month case, the decline for one
month would be (430-292)/430 = 0.321 or 32.1%. annualized, this would
be 0.99 or 99%.

here is the formula for calculating annual decline from any time
period, say one month, one week, one day or indeed one year.

de=1-(q/qo)^(1/t) , where:

de is fractional annual decline rate
q is production rate at time t
qo is production rate at time t=0
%decline is fractional decline x 100
and t is expressed in years, so for the example given,

de= 1-(292/430)^12 = 0.99 or 99 %

note that t is one month or 1/12 years and 1/t is 12. it is not as
complicated as it might seem, excel will handle the math in a flash,
just be sure the formula is entered correctly.

https://groups.google.com/forum/m/?fromgroups#!topic/bakken-shale-discussion/dkNkKdA_COo

As you can see GGE hasnt reached that 99% decline rate as yet... It has also been pointed out elsewhere that the well closed down close to Des got down to 10 bopd in low oil prices.

T1