Proof-of-concept of moving through casing resistivity apparatus. Final report, October 1, 1989--January 31, 1993

ParaMagnetic Logging, Inc. (PML) demonstrated for the first time during 1990 in a Test Well located in Forth Worth, Texas that formation resistivity could be measured, in-principle, from within cased wells with the Through Casing Resistivity Tool (TCRT) designed and built by PML. Early results from this first instrument provided the impetus to investigate measurements methods to increase data acquisition rates and mechanical designs to improve vertical resolution which were implemented in the second experimental version of the TCRT. PML investigated the design requirements for a tool that could continuously move upward within a cased well. It was found that although such measurements can be done, various interfering signals, including those identified as due to the Triboelectric Effect, would mask the weak borehole casing signals if standard wirelines and components from the industry are utilized which limit the amount of electrical current delivered to the well. Extensive laboratory measurements were performed with the Moving Test Jig to investigate the properties of the Triboelectric Effect. Successful methods of measurement were devised to achieve acceptable performance objectives and to overcome problems with the Triboelectric Effect. One such method is called the Slider Method of Measurement