Standard Guide for Conducting Borehole Geophysical Logging: Mechanical Caliper
|Publication Date:||10 September 1997|
|ICS Code (Mechanical testing):||19.060|
1.1 This guide covers the general procedures necessary to conduct caliper logging of boreholes, wells, access tubes, caissons, or shafts (hereafter referred as boreholes) as commonly applied to geologic, engineering, ground-water and environmental (hereafter referred as geotechnical) investigations. Caliper logging for mineral or petroleum exploration and development are excluded.
1.2 This guide defines a caliper log as a record of borehole diameter with depth.
1.2.1 Caliper logs are essential in the interpretation of geophysical logs since they can be significantly affected by borehole diameter.
1.2.2 Caliper logs are commonly used to: measure borehole diameter, shape, roughness, and stability; calculate borehole volume; provide information on borehole construction; and delineate lithologic contacts, fractures, and solution cavities and other openings.
1.3 This guide is restricted to mechanically based devices with spring loaded arms, which are the most common calipers used in caliper logging with geotechnical applications.
1.4 This guide provides an overview of caliper logging including: general procedures; specific documentation; calibration and standardization, and log quality and interpretation.
1.5 To obtain additional information on caliper logs see Section 9 of this guide.
1.6 This guide is to be used in conjunction with Guide D 5753.
1.7 This guide should not be used as a sole criterion for caliper logging and does not replace professional judgement. Caliper logging procedures should be adapted to meet the needs of a range of applications and stated in general terms so that flexibility or innovation is not suppressed.
1.8 The geotechnical industry uses English or SI units. The caliper log is typically recorded in units of inches, millimetres or centimetres.
1.9 This guide does not purport to address all of the safety and liability problems (for example, lost or lodged probes and equipment decontamination) associated with its use.
1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.