Borehole Inspection System for Large Diameter Holes

摘要

A color camera developed for underwater applications has been adapted for use as a large diameter Borehole Inspection System (BIS). This video/photographic system has pan and tilt capabilities and remotely interchangeable lenses. A compass provides an azimuth for orientation. It is designed to operate in boreholes ranging in diameter from 1.2 m to 3.0 m. The system has a 180 degree 'fisheye' lens and an inspection lens with zoom. 35 mm photographs can be taken of the same view as the video for precise location. Video tape and 35 mm film is annotated. The primary function of the BIS is geologic investigation. Various characteristics of the geologic medium can be viewed. Lithologic types and textures can be determined. Structural features such as faults, fractures, and bedding can be scrutinized. Detail descriptions of stratigraphic sequences and contacts are possible. In combination with other borehole data and sample information, many questions about hole conditions and the geologic medium can be resolved. Field operations often demand immediate resolution of borehole problems. This system offers on-the-spot visual inspection of the drill hole and associated hardware. Large eroded zones can be evaluated and casings and liners can be inspected. Other applications such as the location and configuration of hardware left in the hole and fluid entry points are possible. (ERA citation 13:006578)