What is it?
A technique also known as borehole logging, that is used commonly to help measure the resistivity and potential of an excavated area. Well logging has evolved throughout the years to the highly advanced stage it is at today. In further detail, it is a process of recording various physical, chemical, electrical or other properties of the rock and fluid mixtures that are penetrated by drilling a borehole into the earth’s crust.
How old is it?
Speculation is rife about how far the technique stretches back with certain sources saying that in the early 1800’s a quite primitive technique of writing down what sort of disruption was written down on a simple piece of paper.
With advancements in technology down the years, the 1900s brought with a pioneering man called Conrad Schlumberger who twigged that electrical recordings would yield the most accurate figures. Paired with his brother Marcel, he successfully engineered the world’s first electrical resistivity well log.
What are the different types?
As with any logging production, different companies like to implement different techniques depending on the circumstances.
Resistivity Logs – The procedure created by Schlumberger is still effective to this day in detailing the current flowing through rocks and sediments. Different fluids such as oil and fresh water are able to be determined using this tried and tested form of well-logging.
Spontaneous Potential Logs – a solution used to determine whether the subject is shale or sandstone, this analyses the rocks in the well to figure out the permeability and in turn, whether or not it is suitable for drilling.
Induction Logs – for usage in typically dry wells, this technique is implemented to help understand resistivity of the area by utilising magnetism and electricity.
Why use well logging?
Anyone in the logging industry will tell you that is an essential tool in the field and without it, difficulties would arise in any further project. A staple for its sector, well-logging is going to be around for many years to come.