A mudlogger positions hydrocarbons with respect to depth. Oil company geologists are very good at identifying areas in which to drill, and many of these are well known within the industry. If the earth had been formed evenly, there would be no need for my job since the same hydrocarbon bearing formations would be found at the same depth no matter where the drilling was done. Thankfully the earth heaves as geological events occur and formations can be found at different depths even within a close radius.
Enter the mudlogger. We “well sit” while drilling is going on and take samples of the rock brought up the hole, or annulus, by the drilling fluid (mud), as well as monitor produced hydrocarbons. These samples are subjected to tests with chemicals and peered at through a microscope to determine their makeup. It is important to note that many different rocks might hold oil or gas, but the easily producable zones are usually sandstone, followed by limestone. These are fairly porous formations. Shale can be produced, but it is difficult and expensive to do so.
We draw a log which is an analog of the hole using software common to our profession so a geologist may see which formations can be produced. This information is invaluable when deciding where to frac (fracture) which is what it sounds like…you “bust up” a formation so that the oil or gas can more easily flow.
Continual monitoring of produced natural gas may also help prevent blowouts which can destroy equipment and kill people. In short, everyone should love us, but there is this stigma that follows:
The Lazy Mudlogger:
Well, this isn’t a hard job, or even very physical at all unless rigging up or down the mudlogging unit. The heaviest thing we have to carry is about seventy pounds, and you only have to do that once at rig up and once at rig down. This is probably where the moniker comes from when you consider that roughnecks are some of the hardest working people you’ve ever met. They endure the weather 24/7 as a drilling rig stops for no man. Ever seen a 36″ pipe wrench? They’re friggin huge and not very light. Roughnecks use them as key chains. Ok, the keychain part is not true, but everything on an oil rig is made up of thick steel and must be twisted, beaten or cajoled into submission by a roughneck, and usually while their boss (Driller), or their boss’s boss (Toolpusher)or their boss’s boss’s boss (Company man) is breathing down their neck (yelling at them). So it is understandable that they view the guy in the air conditioned trailer who has to carry about a half pound cup of ground up rocks fifty or sixty feet once or twice an hour as lazy. We don’t hate them for it.
In fact, as I type this we are drilling ahead at fourteen feet per hour, so I won’t have to make that trek to collect a thirty foot sample for another two hours.
I think I’ll make some coffee.
I can tell you that your mudlogger can make or break you. We rely on them for much more than collecting samples and tying HC to depths. They also keep us informed as to the status of drilling on the rig, any problems, any successes…they are the conduit between the geologist and the rig crew. Having and keeping a good one is important and makes applying the science and interpreting the data that much easier.
great web sight stan, love you, mom
Stan, really nice site you have here. This brings back many happy memories. My first “real” job was working for the The Analysts (Lafayette, LA) which got bought out by Schlumberger just before I hired on in 1979. Those were the old fashioned days of mudlogging. Hand writing the data on pad and them using a pen to ink it on the velum. Did a few land jobs but most of my time was offshore. I also got involved in the MWD program when it was going commercial. Lots of great memories and stories
Thanks Mark! I really enjoy mudlogging, but I am glad we don’t have a basket of colored ink pens and a big tablet laid out..I kind of like the computer logs. I’d love to have you write a post or two for this site if you like.
The Mudblogger (Stan)
Love how you word the description, I’m also a mudlogger myself in Oklahoma and when people ask me what I do it’s hard to get them to understand because alot of them don’t work in the oilfields. Once again great description…