Calculating Borehole Geometry from Standard Measurements of Borehole Inclinometry.

• Main Authors: Jezek,K C, Alley,R B
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
• Format: Text
• Language: English
• Published: 1984
• Subjects: Snow; Ice and Permafrost; Theoretical Mathematics; *BOREHOLES; MATHEMATICAL MODELS; MEASUREMENT; TRANSFORMATIONS(MATHEMATICS); APPROXIMATION(MATHEMATICS); SLOPE; GEOMETRY; AZIMUTH; GREENLAND; CALCULATORS; ICE CAPS; CARTESIAN COORDINATES; Linear variation models; Quadratic variation models; Inclinometry data; Greenland; Dye 3; Dye-3; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA145006; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA145006

This report describes two new methods for computing borehole geometry from discrete measurements of borehole inclination (theta) and azimuth (alpha). In the first method theta and alpha are assumed to vary linearly with arc length. This results in an analytic model of the borehole that is continuous but not smooth. The second model, which takes theta and alpha to vary quadratically with arc length between three measuring points, improves the smoothness of the model but the analysis must be carried out numerically. These models were applied to the borehole inclinometry data collected at DYE-3, Greenland. The methods were found convenient to use and it is claimed that the results represent physically reasonable approximations to the borehole geometry. (Author)