| Scintillation Crystal |
A device which responds to incoming gamma rays by emitting photons. |
|
| SCT |
Short Combination Toolstring. |
|
| Secondary recovery |
Recovery of oil or gas from a reservoir by artificially maintaining or enhancing the reservoir pressure by injecting gas, water or other substances into the reservoir rock. |
|
| Sensor |
Any measurement device. |
|
| Shut In |
To close the valves at the top of a wellbore. |
|
| Shutdown |
A production hiatus during which the platform ceases to produce while essential maintenance work is undertaken. |
|
| Sinker Bar |
A passive device to add weight to a toolstring. Cf. SWB. |
|
| Slickline |
A thin, usually single strand, of steel wire, used to deploy various mechanical devices into a well. Also used for MPL. |
|
| Slope |
Gradient. |
|
| Sonde |
A downhole instrument connected to a well-logging cable, used in making measurements of parameters related to the borehole or its environment. |
|
| Source |
In well logging, the source of radiation used in the operation of radioactivity logging tools, eg Sondex FDR. |
|
| Springbow Centraliser (PSC) |
A device with spring-loaded arms, designed to ensure centralisation of all or part of a toolstring, |
|
| Spud-in |
The operation of drilling the first part of a new well. |
|
| STDI |
Telemetry & Depth Interface: a PC ISA acquisition card. |
|
| Surface Readout (SRO) |
A system of real-time logging, using a monocable or multi-conductor logging cable. |
|
| Suspended well |
A well that has been capped off temporarily. |
|
| SWB |
Steel Weight Bar: a heavy weight which may be added to a toolstring to allow the toolstring to descend, particularly in situations of high pressure or heavy well flow. |
|
| Swivel Joint (PSJ) |
A passive device inserted into a toolstring to allow rotation whilst maintaining electrical through connection. |
|
