BOREHOLE FLOWMETERS - FIELD APPLICATION AND DATA-ANALYSIS

This paper reviews application of borehole flowmeters in granular and fractured rocks. Basic data obtained in the field are the ambient flow log and the pumping-induced flow log. These basic logs may then be us ed to calculate other quantities of interest. The paper describes the applications of the Tennessee Valley Authority (TVA) electromagnetic ( EM) flowmeter in a granular medium. In an attempt to ascertain the eff ect of formation disturbance on flowmeter readings, test wells were su bjected to repeated periods of development using air lifting. Between the development periods, flowmeter tests were run. The results indicat ed that flowmeter data are not highly sensitive to formation disturban ce in the near vicinity of a test well. Evidence of changes in the nat ural (ambient) flow in the test well was attributed to high, variable rates of pumping by nearby chemical plants. In fractured media, flowme ters may be used to detect flow to or from individual fractures or fra cture zones. In these applications, additional information in the form of caliper, televiewer and resistivity logs are useful. Further studi es of the type described herein are warranted.