Study on density logging of water wells, 1

In order to study the density logging using a decentralized sidecolimated tool, the seven iron-cased water-wells were selected from many existing water-wells distributed in Chuen region, Shizuoka Prefecture. The data obtained by testing in these iron-cased water-wells were interpreted using assistantly geological columns and the resistivity logs and are essentially based on the followings; (1) bulk densities of granular aquifers are generally in the range from 2.0 to 2.3 grams per cubic centimeter, (2) checking the short- and long-spacing of probe with a changeable holesize, and (3) calibration curves for the density logging equipment. In consequence, it was possible to correlate stratigraphic intervals in the left zone of Ota river basin and to clarify approximate permeabilities and the density range (from 2.0 to 2.3 grams per cubic centrimeter) of aquifers in the Chuen region. (author)