ASX ANNOUNCEMENT26 March 2008DRILLING AT HUTABARGOT JULU GOLD...

ASX ANNOUNCEMENT
26 March 2008
DRILLING AT HUTABARGOT JULU GOLD PROSPECT
CONFIRMS POTENTIAL FOR MAJOR EPITHERMAL SYSTEM
HIGHLIGHTS
• Latest drilling completed at Hutabargot Julu (Pungkut Gold Project, Indonesia).
• Assay results from Sarahan Vein include:
�� 1 metre at 8.61 g/t gold from 64 metres
�� 5 metres at 2.12 g/t gold from 23 metres
�� 6 metres at 2.07g/t gold from 16 metres
�� 3 metres at 2.66 g/t gold from 48metres
�� 2 metres at 2.67 g/t gold from 120 metres.
• Drilling has encountered massive alteration at depth with potential to overlie a
large epithermal system.
• High grade mineralisation identified at newly discovered Ali Vein, located west
of the Sarahan Vein including rock chip assay samples of 136 g/t gold; 15.8 g/t
gold; 11.2 g/t gold; 61 g/t gold; 22.7 g/t gold and 1,250 g/t silver.
• Drilling at Sarahan Vein to re-commence during June quarter after exploratory
drilling at Ali Vein.
Oropa Ltd (ASX: ORP) is pleased to announce initial drilling results from the Hutabargot Julu prospect,
part of its 75%-owned Pungkut Gold Project in Indonesia and the discovery of a new high-grade vein
system located to the west of the Sarahan Vein.
Assay results from the initial drilling program at Hutabargot Julu, which included best intersections of
1metre at 8.61 g/t gold from 64 metres and 5 metres at 2.12 g/t gold from 23 metres have
demonstrated the upside potential of the target.
25 Charles Street, South Perth WA 6151 PO Box 1013, South Perth WA 6951 Page | 3
Telephone: (08) 9368 4544 Facsimile: (08) 9368 4522
Web: www.oropa.com.au Email: [email protected]
ACN: 009 241 374
The only deep hole drilled into this Sarahan Vein system intersected massive alteration which has the
potential to overlie a large epithermal system with high grade mineralisation. The extent and continuity
of the veins indicate that the system is not only extensive laterally, but will persist to depth.
High grade mineralisation has also been identified at the newly discovered Ali Vein, which is located
400m to the west of and striking obliquely to the Sarahan Vein. The Ali Vein is 1m wide in
outcrop and silicified breccia with minor manganese returning grades ranging from 2 g/t to 136
g/t Au and significant silver credits over a 330m strike length. A drilling rig is currently being
moved to the Ali Vein to drill the first of an initial program of 6 holes to test the orientation and
extent of mineralisation along the exposed strike.
Hutabargot Julu has been selected as Oropa’s primary exploration target owing to:
�� Potential to host very high grade mineralisation - grades up to 136 g/t Au already encountered;
�� Proximal location to Sihayo-Sambung deposits with Inferred Resources presently totalling
710,000oz – updated resource estimate due in early April;
�� Alteration is associated with a major hydrothermal system and the presence of jasperoid gold in
the Permian sediments at the nearby Dolok prospect indicates continuity with similar style
mineralisation occurring at Sihayo and Sambung;
�� Miocene volcanics are regarded as being a better host for brittle fracture and formation of high
grade veins, as opposed to the more porous Permian limestones that form the bulk of lower
grade deposits;
�� Consistent with the veins being hosted in younger Miocene volcanics and interpreted to have
had relatively little erosion, the predominantly chalcedonic vein textures with minor ghost bladed
calcite indicate that the upper levels of the system are preserved;
�� Studies of other epithermal vein systems show strong vertical stratification and that very rich gold
mineralisation may underlie weakly mineralised or barren veins near to or at surface (see Figure
1); and,
�� The predominantly north-south orientation of the veins indicates the veins form tension-gash
structures in the northwest-southeast orientated Sumatran Fault Zone, an ideal structural
environment for major gold mineralisation.
25 Charles Street, South Perth WA 6151 PO Box 1013, South Perth WA 6951 Page | 4
Telephone: (08) 9368 4544 Facsimile: (08) 9368 4522
Web: www.oropa.com.au Email: [email protected]
ACN: 009 241 374
About Hutabargot Julu
The prospect is located 5.5km to the south of Oropa’s Sambung prospect at the south-eastern end of
the Sihayo-Sambung mineralized trend. Parallel sets of epithermal veins interpreted up to 3km in
length occur in Miocene volcanics, which overlie Permian sedimentary-volcanic basement.
A long history of exploration in Hutabargot Julu area has occurred, as early as 1911 with extensive
exploration adits dug by Dutch explorers, and followed up in 1985 by a CSR / Billiton joint venture with
soil and surface sampling resulting in 3 diamond holes being drilled. That program concentrated on the
highest results obtained from a soil sampling program and did not target the vein structures
currently under investigation by Oropa.
Figure 1: Schematic cross-section model for epithermal systems
25 Charles Street, South Perth WA 6151 PO Box 1013, South Perth WA 6951 Page | 5
Telephone: (08) 9368 4544 Facsimile: (08) 9368 4522
Web: www.oropa.com.au Email: [email protected]
ACN: 009 241 374
To date, Oropa has drilled 13 diamond drill holes at Hutabargot Julu, 8 of which have targeted
the Sarahan Vein at shallow depths to define the geometry of the vein, with one step back hole
intersecting the vein from 138-207m depth after the first planned deep hole failed to reach target
depth owing to mechanical problems. Three shallow holes have been drilled at the Sunday Vein,
1km to the east of Sarahan.
Early drilling at the Sarahan Vein over 300m of strike has established that the vein dips
consistently at 60º to the west. It consists of 5 to 70m down-hole thicknesses of variable
silicification, massive silica replacement, quartz veining, and silicified hydrothermal brecciation.
The hanging wall is invariably strongly oxidised, down to the deepest intersections below 138
metres from surface, associated with draw-down of meteoric waters and the gold mineralisation.
All holes drilled at Sarahan have intersected mineralisation, averaging 2.3 g/t Au over 2.6m
interval. Fossil wood fragments at 100m depth in HUTDD004 indicate brecciation associated
with diatreme activity. The deepest hole to date, (HUTDD013) intersected colloform banded
matrix of hydrothermal brecciation over a 67m interval, indicating that the strength of alteration is
increasing with depth. Drill results are summarised in Table 1.
Drilling at the Sunday Vein targeted a 3-4 metre wide vein that has been interpreted up to 1.4km
strike length. Only moderate alteration was encountered and drilling was suspended pending the
results of further surface exploration and evaluation of other newly discovered veins within the
prospect area.
Further deep drilling is warranted along the Sarahan Vein. Oropa considers that the initial drilling
has already demonstrated the potential of a large target at depth. A re-commencement of drilling
at Sarahan is scheduled during the June quarter after reconnaissance drilling at the Ali Vein is
completed.
25 Charles Street, South Perth WA 6151 PO Box 1013, South Perth WA 6951 Page | 6
Telephone: (08) 9368 4544 Facsimile: (08) 9368 4522
Web: www.oropa.com.au Email: [email protected]
ACN