Two Decades of Electrical Logging

Abstract

The present paper, written at the request of the editor of the JOURNAL OFPETROLEUM TECHNOLOGY, gives a brief history of the various logging methods andof their progressive development during the last 20 years. More generally, itrefers to the different operations performed in drill holes at the end of anelectric cable to locate the permeable formations and to determine theircharacteristics, such as porosity, fluid content, and dip; to procure samplesof the formation by sidewall coring; and to determine data concerning the drillhole itself, as, for example, its diameter and deviation from vertical.