WellCAD Basics - Advanced Logic Technology

144 - BOOK 1 - WELLCAD BASICS
1.5.10 Zonation of Logs
The zonation process is based on Ward´s method
of hierarchical cluster analysis. The input data
consists of one or multiple logs that the user
selects. After standardization of the log data to
ensure that each data set has equal influence on
the zonation an iterative process will commence.
Starting by treating each observation as a single
zone the Euclidean distances between the
observations available in each iteration step will be
calculated. The pair with the closest distance
difference will be selected as a composite zone and
treated as a single observation during the following
iteration step. The iteration continues until the
user specified number of zones has been reached.
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The example to the right has been created from
four input logs (Gamma Ray, Density, P Slowness
and Neutron Porosity) for 5, 10, 20 and 40 zones.
To start the process select Process > Common
> Zonation. A dialog box will open allowing to
specify the input logs (Well Logs) and the number
of zones to fit.
Zonation options dialogue