The application of detailed gravity to define
sub-basaltic structure and to locate drill-sites
for gold mineralisation.
Hugh Rutter, Flagstaff GeoConsultants
Ballarat-Allendale-Clunes Area
VIMP Bravity
5,885,000N
5,880,000N
5,875,000N
CLUNES
Clunes
5,870,000N
5,865,000N
ALLENDALE
Allendale
5,860,000N
5,855,000N
5,850,000N
5,845,000N
mgls
-15
5,840,000N
BALLARAT
Ballarat
-20
-25
5,835,000N
-30
745,000E
750,000E
755,000E
760,000E
765,000E
Ballarat - Allandale - Clunes Area
VIMP Gravity
770,000E
775,000E
780,000E
Ballarat-Allendale Clunes Area
Private Company Data (15,000
stations)
5,885,000N
5,880,000N
5,875,000N
CLUNES
5,870,000N
5,865,000N
ALLENDALE
5,860,000N
5,855,000N
5,850,000N
5,845,000N
5,840,000N
BALLARAT
5,835,000N
5,830,000N
5,825,000N
745,000E
750,000E
755,000E
760,000E
765,000E
770,000E
Ballarat - Allendale - Clunes Area
Private Company Data ( 15,000 stations)
Hugh Rutter, Flagstaff GeoConsultants Pty. Ltd. February 2007
775,000E
Ballarat-Allendale Clunes Area
Private Company Data (Contour
Interval 0.2mgls)
5885000
5880000
5875000
CLUNES
Clunes
5870000
5865000
ALLENDALE
Allendale
5860000
5855000
5850000
5845000
5840000
Ballarat
BALLARAT
5835000
5830000
5825000
745000
750000
755000
760000
765000
770000
Ballarat - Allendale - Clunes Area
Private Company Data ( Contour interval 0.2mgls)
Hugh Rutter, Flagstaff GeoConsultants Pty. Ltd. February 2007
775000
5,864,000N
Allendale – Company Gravity Contours
5,863,500N
5,863,000N
5,862,500N
5,862,000N
5,861,500N
Allendale
Allendale
5,861,000N
5,860,500N
5,860,000N
5,859,500N
5,859,000N
5,858,500N
5,858,000N
5,857,500N
mgls
-14
-14.5
-15
5,857,000N
-15.5
-16
-16.5
-17
-17.5
5,856,500N
-18
-18.5
-19
-19.5
-20
5,856,000N
755,000E
755,500E
Reduction density: 2.67g/cc
Terrain corrections applied
Contour interval: 0.5mgls
756,000E
756,500E
757,000E
757,500E
758,000E
758,500E
759,000E
500m
1,000m
1,500m
2,000m
Allendale
Company Gravity Contours
Flagstaff GeoConsultants
Hugh Rutter, February 2007
759,500E
Scale 1: 12,500
0m
2,500m
760,000E
760,500E
761,000E
761,500E
762,000E
5,864,000N
Allendale Company Gravity Contours with some structural lines
5,863,500N
5,863,000N
5,862,500N
5,862,000N
5,861,500N
Allendale
Allendale
5,861,000N
5,860,500N
5,860,000N
5,859,500N
5,859,000N
5,858,500N
5,858,000N
5,857,500N
mgls
-14
-14.5
-15
5,857,000N
-15.5
-16
-16.5
-17
-17.5
5,856,500N
-18
-18.5
-19
-19.5
-20
5,856,000N
755,000E
755,500E
Reduction density: 2.67g/cc
Terrain corrections applied
Contour interval: 0.5mgls
Flagstaff GeoConsultants
Hugh Rutter, February 2007
756,000E
756,500E
757,000E
757,500E
758,000E
758,500E
759,000E
759,500E
Scale 1: 12,500
0m
500m
1,000m
1,500m
2,000m
Allendale
Company Gravity Contours
with some Structural Lines
2,500m
760,000E
760,500E
761,000E
761,500E
762,000E
5,842,000N
Ballarat Area – Company Gravity Contours (Contour Interval 0.1mgls)
5,840,000N
Ballarat
BALLARAT
5,838,000N
5,836,000N
5,834,000N
750,000E
752,000E
Ballarat Area
Company Gravity Contours
(Contour interval: 0.1mgl)
Hugh Rutter, Flagstaff GeoConsultants Pty. Ltd. February 2007
754,000E
5,842,000N
Ballarat Area – Company Gravity Contours with some structural lines
5,840,000N
Ballarat
BALLARAT
5,838,000N
5,836,000N
5,834,000N
750,000E
752,000E
Ballarat Area
Company Gravity Contours
Plus some structural lines
Hugh Rutter, Flagstaff GeoConsultants Pty. Ltd. February 2007
754,000E
Company Gravity – Clunes Area (Contour Interval 0.1mgls)
Clunes
Clunes
5,870,000N
See Slide 12
for section
5,869,000N
5,868,000N
746,000E
747,000E
Company gravity Clunes area
Contour interval: 0.1mgl
Company Gravity – Clunes Area showing relationship between gravity data and an aggregate of past dividends
New North
Clunes
241,800 oz Au
Port Phillip
512, 800 oz Au
Together dividends
paid
= £1m sterling
• Reference: R.A.Binns and J.C.Eames
• Geochemistry of Wall Rocks at the Clunes Gold
Deposit, Victoria. Economic Geology, 1989, Vol 24, pp 310-319
•
“Given the otherwise comparable nature of remote and proximal wall
rocks, the lower densities of the altered zone at Clunes, averaging 0.1 g/cc,
might be detectable by gravity survey.”
-21.9
Relationship between gravity data and drillhole CD06-1 with gold assays
-22
-22.2
-22.3
-22.4
-22.5
746,500E
746,600E
746,700E
746,800E
746,900E
747,000E
CD06-1
Scale 1: 2,500
ppb
)
0
Go
ld (
10 ,
000
20 ,
000
3 0,
00 0
Ground surface
40 ,
0 00
milligals
-22.1
Mount Rommel Mining Limited
Clunes
Relationship between gravity data
and drillhole CD06-1 with gold assays
Flagstaff GeoConsultants
Hugh Rutter, November 2006
• Conclusion
– Gravity can be used in the regional sense to define and
delineate structure and lithology.
– Detailed gravity can define areas of altered Palaeozoic
basement which may be prospective for gold mineralisation
– Gravity modelling is recommended to distinguish gravity
anomalies sourced in the regolith.
– Selected IP/Resistivity lines over the local gravity anomaly
may more accurately define sulphide mineralisation
associated with gold bearing quartz reefs.
The support of Mount. Rommel Mining Ltd, who supplied the data, is gratefully
acknowledged. Website: www.mountrommel.com