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Subsurface exploration for foundation design
Published in An-Bin Huang, Hai-Sui Yu, Foundation Engineering Analysis and Design, 2017
A wireline system can be used to take rock cores in a deep borehole. In this case, a thick casing is used to serve the purpose of the drill rod. A wireline (a steel cable) is used to either lower or retrieve the drill bit or core barrel to or from the bottom of the casing/drill rod. The arrangement eliminates the need to remove all the drill rods from the borehole in order to replace drill bit with the core barrel, and thus saves time and effort. The wireline system can also be used when taking the soil samples in deep boreholes.
Subsurface SHMAX determined from a borehole image log, onshore southern East Coast Basin, New Zealand
Published in New Zealand Journal of Geology and Geophysics, 2019
Petroleum exploration wells have been drilled in the East Coast Basin since the late nineteenth century (Figure 1). Most of the geological information obtained from these wells has consisted of cuttings and conventional wireline log data (e.g. natural gamma, resistivity, sonic, and density logs can provide information on the lithology in the well) (e.g. BP Shell Aquitaine Todd Petroleum Developments Ltd 1976; Biros et al. 1995; Tap Oil Limited 2004). In recent decades, borehole imaging tools have been used in many wells overseas, providing an opportunity to compensate or complement information obtained from cuttings, core, and traditional wireline data sets taken in the well (e.g. Bell and Gough 1979; Prioul and Jocker 2009; Nie et al. 2013). Using image logs has in the past been considered an added expense, so are often not used in this country. Some recent wells however, including some in the Taranaki and East Coast basins, and the Taupo Volcanic Zone, have had borehole televiewer (BHTV) or resistivity imaging tools run in them and the data acquired from these imaging tools can provide valuable new information on the subsurface geology and structure (e.g. NZEC 2012a, 2012b; Rajabi et al. 2016; McNamara et al. 2017; Griffin 2018).
Improving geological logging of drill holes using geochemical data and data analytics for mineral exploration in the Gawler Ranges, South Australia
Published in Australian Journal of Earth Sciences, 2021
E. J. Hill, A. Fabris, Y. Uvarova, C. Tiddy
The application of CWT methods for extracting geological boundaries has been widely tested for wireline logging in the petroleum industry (e.g. Arabjamaloei et al., 2011; Cooper & Cowan, 2009; Davis & Christensen, 2013; Panda et al., 2000; Perez-Muñoz et al., 2013). Unfortunately, these methods require an expert in wavelet transforms to interpret the results, for example, Figure 4b. However, CWT can be combined with a modified tessellation method, described below, to convert the scale-space plot resulting from the CWT into a plot that resembles a geological log plotted downhole (depth on the y-axis), but with the addition of scale information plotted on the x-axis.
Correlation of the lithostratigraphic facies relationships and depositional environments of the uppermost Silurian through Lower Devonian strata across the central Darling Basin, western New South Wales, SE Australia
Published in Australian Journal of Earth Sciences, 2021
Re-evaluation of the positions of the lower Winduck Interval sequence in the Booligal Creek 1 and 2 wells was based on well correlation of detailed lithology from full core information and tied wireline-log patterns data from Bancannia South 1 and Pondie Range 1 wells (Figure 3). The maximum thickness of lower Winduck Interval sequence has been recorded from Pondie Range 1 well at 207m in the southern Pondie Range Sub-basin, thinning towards the central Bancannia Trough to 120m in the Bancannia South 1 well (Figure 3).