Abstract

Major achievements have been realized in almost 75 years of wireline logging. This paper outlines the major advancements that have been made in the industry since the first wireline log was recorded in 1927.

The arsenal of wireline measurements has grown to allow an unprecedented understanding of hydrocarbon reservoirs. During the last ten years the use of the computer both at the wellsite and the office along with advanced downhole instruments has had a major impact in the entire industry. With these advancements, it is possible to transmit up to 500 K bits per second of data from the downhole sensors along with simultaneous data transmission to all parts of the world. Data can now be displayed as images, which leads to an improved understanding of the geology and reservoir properties. Advancements in formation fluid sampling and pressure measurements have made these services more routine and cost effective. A new Open Hole Quad combo – rated to 500 degrees – known as Xtreme is now being introduced for the increasing temperature challenges through the world.

One of the recent significant advancements is in the field of Nuclear Magnetic Resonance Technology, which is also used, in the modem day medical industry. Laboratory Nuclear Magnetic Resonance (NMR) studies of fluids in rocks, on clays, and in other porous media began in the 1950’s at a number of oil company research laboratories. Schlumberger built the first commercial NMR borehole-logging device in the 60’s, however the technology available then was a limiting factor to developing a practical measurement. Measurement technology, which was developed in other industries was applied, and combined with the new magnetic technology, and resulted in the highly successful service, known as the Combinable Magnetic Resonance tool (CMR).

Geomagnetic polarity measurements have been used on surface rocks, which enables a geomagnetic polarity time scale (GPTS) dating back to over 460 million years. The first generation of measurements has been built to try and measure the very small magnetic fields of the reservoir rock. The technology is limited at the present time, due to the accuracy required at very small signal levels. A borehole recording of the magnetic orientation of the sediments promises a direct correlation with the GPTS, which can yield an improved correlation and absolute age determination in the reservoir. This technology is in the beginning stages, much like the NMR measurements were in the early 60’s

Advancements in Nuclear Physics will be one of the main driving forces in the future. The measurement of gamma ray energy levels, known as spectroscopy will play an important role in locating oil and gas behind casing as well as improving knowledge of lithology, porosity and water saturation both in open and cased hole. A significant breakthrough in the design of a new spectral gamma ray detector enabled a smaller tool to be built, which measures through tubing and casing, yielding porosity and water saturation. The intense research involved in detector technology, was passed on to the medical industry, resulting in smaller spectral gamma ray detectors, that produce high resolution x-ray medical images. Flow profile imaging of the fluid flow inside the well casing is now possible using a special electromagnetic probe sensor.

In the future, wireline will only be one of the many ways to “convey” the sensors required to evaluate the reservoir both in open or cased hole. Technology advancement is allowing the development of sensors to be placed in drill pipe and coiled tubing, at an escalating rate. Horizontal drilling records exceeding 10 kilometers in measured depth have already been achieved as a result of having sensors in the drill pipe. Sensors placed in coiled tubing have allowed multi lateral wells to be drilled in existing cased wellbores. High-speed data links allow instantaneous transmission of large volumes of data from the wellsite, directly into client’s offices, in an interactive manner. These advancements are the result of Schlumberger’s commitment to over $1 million USD per day on research and engineering. The future will be driven by oil companies and service companies working together jointly in the concept and development stages to provide new innovations for the industry. The new technology will be developed through various channels such as the client link database, client forums and customer advisory boards.