4) Are the two mudlogging geologists alive? These guys are independent contractors who work on multiple drilling rigs for multiple companies. They are your first line of defense against a blowout, apart from the actual blowout preventers. If these guys are geologists, they are very bright people who have studied in principals of geology, physics, math and chemistry. These sometimes quiet intellectuals are working for the money in 12 hour shifts which can go on un-interrupted for up to a month depending on the site and whether there are other geologists to relieve them. Many do this job out of choice for 20 years. Others only for a few years. If a geologist falls ill and another is not immediately available, that shift is pushed to 24, 36 and 48 hours without sleep. The drilling does not stop to wait for a replacement geologist. The geologist can not leave, until the company gives him authority. In any case, he can not hitch a ride on a passing helicopter. Call to publish the geological mudreport.
5) Are the mudmen still alive? They are your second line of defense against a blowout. They are there to monitor the mud. They have to add more barium sulfate to increase the specific gravity) of the mud (weight up the mud). If there is too much gas coming up with the mud and drill cuttings (broken bits of rock), they must add more barium sulfate. They must thin the mud down by adding water if the gas is being suppressed to such a degree that no gas readings are being detected. They must change the pH (acidity-alkalinity) to cope with different clay conditions that are plugging up the drill bit. They must do saline tests when gas and oil shows are encountered to determine if this is going to be a payable zone. Too much saline with gas or oil can lead to uneconomic wells. Call to publish the Mudman report.
6) The drill crew or roughnecks (ruff necks). How many of them are still alive? If there were 3 eight hour shifts, two thirds should be alive. Your third line of defense against a blowout. They know through years of experience and by working in certain areas and by drilling many wells, what is likely to be happening there. They know when it is time to slow down the drilling rate so that the mud man can weight up the mud and when it is time to circulate, to allow the drill mud to degas. They are continually checking with the geologists to see what his instruments are reading for the amount of gas detected in the formation. A "kick of gas" is when a new oil and gas horizon is struck and the mud weight is too low for that amount of gas being produced. More barium sulfate needs to be added to weight up the mud. They speak to the mudman who gets the roughnecks to pour in more barium sulfate. They know when it is time to "wipe the hole" A term used when all the drilling pipes are taken out to make sure that the hole is free of sticky cloying clay and that there are no broken teeth or buttons on the drill bit. Call to publish the roughneck 8 hourly reports.
7) Geophysical Borehole Loggers or Wireline Logging engineers. These people produce E-logs or electrical logs.
Once the well is drilled to the depth required, most of the well is still open, that is it has not been cased by steel piping. It could cave in, if it were not for the drilling mud in the hole to support the well sides and to keep the gas and oil out.
It is now time to run the wireline electronic logs (e-logs). These logs are continuous paper and digital displays that measure among other parameters, porosity, permeability, spontaneous potential, resistivity, sonic properties, active and passive nuclear measurements, dimensional measurements of the wellbore, formation fluid sampling, formation pressure measurement and others. In wireline measurements, the logging tool (or probe) is lowered into the open wellbore on an armored wireline. Once lowered to the bottom of the well the measurements are taken on the way out of the well. Sometimes these e-log instruments can get stuck in the mud or the sidewall of the well, resulting in the loss of a well. Some e-logs have radioactive sources to measure changes in radioactivity. These need to be cemented in to prevent radioactivity from reaching the environment. E-logs instruments in open holes can also lead to blowouts if the instrument gets stuck for a long time. The heavier part of the mud, the barium sulfate settles out at the bottom of the well, the mud thins and can no longer keep the oil and gas pressure from entering the hole. A blowout results.
These e-logs are used to measure a number of parameters in this open hole, to help correlate and understand the potential zones for oil and gas that have been picked up by the mudlogging geologist and the 3 dimensional aerial sonar and electrical resistivity surveys that were first done by geophysicists to choose this particular well site.
If the three can agree with each other, they have a great understanding of what is taking place at this site and where the particular oil and gas zones are and how thick they are.
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