Electrical and electromagnetic methods - Geophysics for the Mineral Exploration Geoscientist - page 338

W E a) b)

SH20

North loop

Gossan

Zone 3
mineralisation

Zone 1
mineralisation
(projected)

Current
filament

West loop Central loop

SH20

Cross-
section

Zone 4
mineralisation
(projected)

Current
filament

Grid

0 50

Metres

0 100 South loop

Metres

c)

Response (nT/s) Response (nT/s) Response (nT/s) Response (nT/s) Response (nT/s)

-100 0 +1 0 0 -100 0 +1 0 0 -100 0 +1 0 0 -100 0 +1 0 0 -100 0 +1 0 0

0

100

200

Western
loop

Central
loop

Eastern
loop

Southern
loop

Northern
loop

300

d)

Response (nT/s) Response (nT/s) Response (nT/s)

-100 0 +100 -100 0 +100 -100 0 +100

0

Central
Loop

100

200

A component U component V component

300

Figure 5.95 DHEM data from Balcooma massive sulphide. (a) Geological cross-section, (b) location of the

five transmitter loops around

drillhole SH20, (c) axial component late-time data from the five transmitter loops, (d) three-component late-time data from the central

transmitter loop. All loops are 200 m 200 m in size. Based on diagrams in Hughes and Ravenhurst ( 1996 ).