Information Extraction from Noisy Televiewer Logs of Inclined Wellbores in Hard Rock

Abstract

A feature extraction method was adapted from satellite image processing to the problem of extracting information from extremely noisy and narrow range televiewer imagery from GT-2 at Fenton Hill. From televiewer logs, 733 structures were recovered, compared with 42 from core. The average spacing were 3.13 and 0.55 feet, respectively, indicating that the televiewer yielded only 17.5% of the information available form core. Two televiewer runs overlapped between 4000 and 4275 feet depth, but no detectable structures were repeated on both runs. The lack of repetition was explained as due to random processes arising from thermally induced electronic noise and manually operator narrow range recording. Two new coefficients of association were defined, termed "co planarity" P, and "co linearity", L, respectively. The co planarity of foliations demonstrated that, despite no repetition of individuals, the two runs could be correlated. The co planarity averaged 60 degrees, falling to 43.5 degrees at match, at a lag of -4.5 feet. There was no systematic maximum in the co planarity for fractures, indicating that these were not serially correlated. A periodicity in the co linearity for foliations indicated a set of folds with wavelength of 80 feet.