A common mistake mud logging companies make when purchasing microscopes is selecting the wrong ones!
I am speaking from experience, I am a Geologist that got my start in the oilfield and did my fair share of mud logging. I spent six years in the oilfield during the beginning of the Shale Revolution from 2008 to 2014 and did a variety of jobs related to collecting geologic data at well sites. I have worked in the Appalachian Basin, South Texas, and Oklahoma among other places. Everywhere I went I saw mud loggers using compound microscopes.
The problem with this is that compound microscopes are for analyzing things that can’t be see with the naked eye like microorganisms. What is needed for examining drill cuttings is a stereo microscope which is used to see larger objects in better detail. For more on the difference between compound and stereo microscopes you can check this post out here.
You can find stereo microscopes suitable for mud logging here, but first read the buying guild below.
There are several things to consider when selecting a stereo microscope for mud logging.
Above: Example Basic Stereo Microscope (Meiji EM-31)
On the surface of things any stereo microscope will suffice, but it is worth spending a little more for added bells and whistles that will allow you to better service the client. These bells and whistles are largely digital cameras and LED lighting.
Stereo, Duel Stereo, or Stereo Zoom Microscopes
Stereo microscopes originally only had one level of magnification. This lead to the introduction of the duel stereo microscope which has two levels of magnification, typically 10X and 30X. For obvious reasons one or two levels of magnification isn’t always enough. For this reason Stereo Zoom microscopes were invented. Stereo microscopes have a range of magnification levels; typically 7X - 45X, which gives 39 different levels of magnification (45 – 6 = 39).
Power Supply: Battery Vs Power Cord
Often times the voltage of devices becomes a consideration in mud logging trailers as each new device with a power cord threatens to cause a circuit breaker to flip, or at the very least causes one less socket to be available. Many stereo microscopes rely on LED lighting and don’t need to be plugged in to operate, and instead run on AA batteries. These microscopes offer the extra benefit of being easier to position and move around in a work station. The downside is that the trailer must always be stacked with extra batteries. It must also be mentioned that this is not the most important consideration, if you have to pick between a microscope that runs on batteries and one that runs uses a power cord but has a better camera, go with the one that has a better camera.
Speaking of Cameras
As mentioned above Digital Microscopes (a.k.a Camera Microscopes) have become more popular in recent years. They come in a range of MP options from 1.3MP to 20MP and can create excellent photos for your client. It is important to keep in mind that as a mud logger you probably don’t need to purchase the most powerful options. In fact, they are probably the wrong choice for several reasons. These cameras produce large files that take up space on hard drives. They are also difficult to email and upload onto finicky rig site internet systems. The geologist you are working for may want to see them on the actual log, which can make the file unmanageable and subject to crashing.
In my day it wasn’t uncommon to see an adjustable lamp next to the microscope. This created unequal lighting issues. Today there is no reason to not buy a microscope with either an incandescent or LED light attached to it and placed in an ideal position so as to provide ample and properly distributed light. Many microscope manufactures also provide LED ring lights that can be affixed to the objective of the microscope.
Keep in mind when shopping for mud logging microscopes to make sure you select the right type (stereo, preferably a zoom stereo), and find one with the appropriate power supply, camera, and lighting.