Geoscience Reference
In-Depth Information
10400
10300
Northing
Elevation
10200
10100
10050
7000
7100
7200
7300
7400
Easting
Easting
Plan view of the deposit
Sectional view (looking north)
eled in true 3-D avoiding projecting to the plane of inter-
pretation. Thorough manual and visual checks should be
performed on each set including plotting at an appropriate
scale the working and final sections and plans.
d. The full set of working and final sections should be avail-
able for auditing. These should be stored as historical doc-
umentation with the full drilling program report. The mod-
eling procedures and criteria, reports of internal checks and
external audits, and production reconciliation information
(if available) should be archived in the same place.
e. Wireframes should be used to build solids (as opposed to
volumes obtained from sectional extrusions), and a full
set of visualization tools should be used in the presenta-
tion of the modeled geology.
f. The interpreted geology should be dynamically updated
as new drill hole information becomes available. This is
particularly important for operating mines where infill
drilling is done on a regular basis and production data also
becomes available on a regular basis.
g. The geologic model should be checked against geologic
flagging obtained through nearest-neighbor estimation.
Volumetric differences and biases should be explained or
resolved, as appropriate.
3.6
Exercises
The objective of this exercise is to perform some basic geo-
metric modeling and work with conventional Cartesian coor-
dinate systems. Some specific (geo)statistical software may
be required. The functionality may be available in different
public domain or commercial software. Please acquire the
required software before beginning the exercise. The data
files are available for download from the author's website—
a search engine will reveal the location.
3.6.1
Part One: Vein Type Modeling
Consider 15 drill holes—3 drill holes from each of 5 drill
stations (labeled as A, B, C, D, and E) to delineate a deposit
with two mineralized zones. Drill stations are aligned N-S
and spaced 100 m, see Figure below.
The deposit is in the shape of two steeply dipping en
echelon ore lenses where the strike direction of the lenses is
approximately northwest. The lower limb is not always min-
eralized. An estimate of the total volume of mineralized re-
source is required. The exercise is to develop sectional draw-
