There will be an interesting phenomena occurring in years to come as gradually more and more of the producing wells in this country are from unconventionals.
Due to its nature, unconventionals produce at dramatically steep early declines but over time, between 7 and 12 years after initial production, the rate of production decline is very, very low, almost constant.
This causes a long ‘tail’ wherein little decline is seen, and this tail could last decades.
Just think of hundreds of thousands of these wells are producing on average say, 10 bopd, almost without decline.
It will alter significantly this country’s production modeling.
I don’t think that is a great change from our existing conventional wells. The later years that is.
The United States has an estimated 771,000 marginal wells in production - about 410,000 oil and 361,000 natural gas wells.
https://nswa.us/custom/showpage.php?id=25
This is not my area of expertise.
Don’t producers pump hot water or steam into old wells to increase production?
Also, doesn’t oil seep into these denuded reservoirs, from below, over time, thus replenishing the reservoir?