The industry of oil and gas has used wireline logging to get a continuous record of the formation and the properties of rocks. Wireline logging can be defined as the acquisition and analysis of geophysical data performed as a function of wellbore depth, together with the provision of related services. It should be taken note that “wireline logging” and “mud logging” are not even similar, yet but the two are closely linked through the integration of the data sets. The measurements are made on reference to “TAH” – True Along Hole depth. These data and the associated analysis can be used to conclude further properties, such as hydrocarbon saturation and formation pressure, and making decisions on further drilling and production.
Wireline logging provides the most detailed information possible for all formation evaluation methods in oil wells. Open-hole logging is the only way to perform continuous record of measurement versus depth on a ground that is made of so many formation properties. Specifically, wireline logging could produce a record of formation electrical resistivity, bulk density, natural and induced radioactivity, hydrogen content, and elastic moduli. All the data on raw measurements then will be interpreted to give a continuous measurement -versus-depth record of formation properties, for example: porosity, water saturation, and rock type. This is the common knowledge that in most cases, every well drilled for hydrocarbons (oil and gas) will be logged with wireline instruments.
The oil price on the market is quite fluctuate, and in certain circumstances, it could increase in abnormal pattern, drastically. Therefore, more and more oil refinery companies are readying themselves up for more drilling, and there will be more wireline logging, to increase their profits as much as possible at the time of high oil prices.
The genuine operation of a log includes lowering certain tool attached to the end of a logging cable into an oil/gas well. A sensor, equipped in a sonde and its associated electronics, is hung into the well connected to a multi-conductor cable. The signals from the sensor are processed by the down hole electronics to be transmitted up to the cable to the control panel on the surface which in turn process the signal to be sent to the recorder. At the moment the cable is raised or lowered, it activates the depth-measuring device, a sheave wheel (pulley) which then activates a recording device. Finally, there will be a process that is intended to provide a hard copy of the recorded data which is called the well log.
Commonly, the jargon of wireline logging differs between a logging survey/run, a logging tool, and a log as well as a curve. It is happening so often that there is some confusion about these terms when logging matters are discussed. A logging survey is the data provided by a logging service company for a client. When process of the logging pass/survey takes place, the logging engineer may use several logging tools at once, and record several different logs with each device of which are visualized by several different curves.