This represents my understanding of these topics. However, if you happen to be an expert on any of these topics, and you see an error, please send me an email at email@example.com so I can fix the error. A video of the inner workings of a LACT meter (no sound) For definitions of words or acronyms, try this link: Minerals Management Service Glossary For pipeline lingo, try this link: Pipeline Dictionary Definitions I didn't find in the MMS Glossary are here. If you need a definition and it's not in the glossary, email me and I'll tell you if I know... In general, shallow wells tend to have oil, deeper wells tend to have more gas. In California, the shallower the wells are, the heavier the oil tends to be. This site has some good links: www.marginalwells.com On diagrams, the color scheme is usually:
The drill bit is connected to the bottom of a series of drill pipes. These are heavy duty steel pipe, about 3 to 5 inches in diameter. Each piece of drill pipe is called a "joint." A joint will be about 30 feet long. This picture is from an advertisement of Petron company.
This is the best picture I've ever seen that illustrates a packer. It is from a Schlumberger ad. This particular one is shown in open hole, but packers are also used inside casing. They are showing two rubber elements: many packers have only one element. Sometimes people refer to packers (and other items) as "tools." They have some widget inside the tool, which you cannot see, and this widget acts to inflate the rubber elements, pushing them against the walls of the hole and sealing the annulus. Generally, they run packers on some sort of pipe, usually tubing or drill pipe, but they can run them on wireline in some cases. On this particular model, it looks like they have a little test port below the bottom packer element. I'd imagine that they must have a test port between the elements as well (either that, or maybe one of the elements is a backup in case the first one doesn't seal all the way). They seal off the formations above the test port so they can make sure they are measuring the pressure (or some other parameter) of just the particular zone they are interested in. I have seen some of these tools work, and they are really pretty slick! Some of them have a little port that comes out (like a robot) and sticks itself to the formation. Then, it sucks in fluid past a sensor and you can see the electrical resistivity of the fluid on the screen in the logging truck. When you pull the tool out, the fluid will be in a chamber inside the tool, and you can run more tests on the fluid. How do you tell a drilling rig from a workover rig? I like my friend Mike Heimer's strategy: "if the rig has a lot of trucks parked around it, it's probably a drilling rig. If it has relatively few trucks around it, it's probably a workover rig." In areas where "triples" rigs are common, you can tell the drilling rigs because they are bigger. But that's not true in areas, like California's San Joaquin Valley, which use "doubles" rigs. Perforating
Perforating - a part of many completion operations
This photo shows some employees of Schlumberger running a test of their perforating equipment. Basically, the perforating gun has a bullet that makes a hole in the casing. Usually, the casing has been cemented in the hole before we perforate. Since the cement is between the casing and the rocks, and the rock contain the oil, the oil cannot get into the well unless we perforate to make a hole in the casing and cement. People call this hole the "perforation tunnel." One question that people have about perforating is, "how far out will the perforation tunnel extend?" We want to make sure that we get the tunnel deep enough that it goes past the cement. Usually, the casing is 1/4 to 1/3 inch thick, and the cement will be another inch or so of thickness. It's no trouble to perforate thru the pipe and cement. At least in theory, the farther out your perforation tunnel goes, the better connection you should have to the reservoir. What the guys in the picture have done is to test out their perf guns in a concrete model. They pour the concrete inside the shiny corrugated pipes, then shoot the perf gun into the concrete to see how far the tunnel extends.
Cross Section of a Perf Test
Here is a cross section of a test similar to the one being run above. Halliburton company tested a couple of perf guns using sandstone cores, and then cut them in half to see where the perfs went. The marks are in inches.
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