This is part of the ongoing series of tech talk posts I make on Sundays about the technology behind some aspects of getting oil, natural gas and coal out of the ground. At the moment, as I noted recently, there are places where it costs more to get the fuel out of the ground than folk are being paid for it, yet they are still pumping it out. There are a number of reasons for this, but I wanted to tie in a comment that goes back to the early days of oil production, when one could find pictures of oil derricks, built one right next to another. That density has been reproduced at Kilgore, TX where at one time they had 1,100 wells producing oil from the Great East Texas Oil field.

Reproduction of well density (from TexasEscapes )

When times got tough each well owner would still produce all the oil possible, why? (Apart, that is from paying the interest on all the money borrowed to drill the well in the first place).