“I have never gone back that far and done anything more than just look at production. But what I had to do for Carey King was to actually look at what was the well performance like in 1950, 1960, and 1970 (…) But what I discovered was, that back in the 1950s and 1960s, the average well was a pretty darn good well in the United States. It was 150.000, 200.000 barrels per well on average (over the “life cycle”).  By the late part of the 20th century, that had dropped down to about 20.000 barrels a day (…)  Now, 20.000 barrels a day sounds like a lot of oil, and it is as a consumer, but there’s hardly a company in the world, that can afford to produce a well that only makes 20.000 barrels in its lifetime.” Arthur Berman: “Shale Oil and the Slurping Sound” | The Great Simplification #101 (Nate Hagens), YT, 13.12.2023

Then, when the tight oil, the deep water and the offshore Gulf of Mexico started coming on, those average wells (initially) were from five to 50 times more productive than even the really good wells back in the mid-part of the 20th century. And the shale wells were in the same category (…) But the real  jaw-dropper in the study, I guess, was looking at US production today, it’s declining at a very  precipitous rate, and (at) the shale plays, again, the average well performance is declining at a  really concerning rate.

What that says, is we’re heading back to where we were in the 1990s and early 2000s, unless I’ve got something very, very wrong. In other words, the unconventional plays bought us about a decade or a decade and a half,  and now we’re probably looking at something (…) similar to when we were worried about peak oil the first time around.”