Bu Dun Hua Porphyry Copper Project
KSO acquired the Bu Dun Hua project in 2007 after
recognizing porphyry Cu style alteration around a modest quartz-hematite
vein system known locally as the Lao Ping Tong mine. Despite
widespread sand and colluvium cover, KSO worked systematically outwards
from Lao Ping Tong and late in 2009, discovered the Whitehorse Cu-Mo
mineralised porphyry intrusive complex. Through 2010, the company not
only established key geological and geochemical criteria for ongoing
exploration at Whitehorse, but also discovered a series of other
potentially mineralised porphyry intrusives forming a structural
corridor both east and west of Whitehorse.
This discovery of this porphyry system, under sand cover
often tens-of-metres thick is considered a validation of KSO’s
selection of Inner Mongolia as an appropriate exploration environment
for low cost discovery of new bulk-mineable porphyry style deposits.
The Bu Dun Hua project is located in a northwest-concave
Palaeozoic fold belt traversed by a NNE trending belt of Mesozoic
intrusives and volcanics that elsewhere hosts a number of significant
epithermal gold, porphyry copper and skarn copper deposits.
Within KSO’s tenement area, outcrop is poor outside of a
prominent, central, northeast trending ridge of silicified felsic
volcanic flows and fragmental rocks Prior to KSO’s involvement,
previous explorers had focused on a small area of precious and base
metal anomalies associated with a series of fault structures on the
south flank of the ridge. The largest of these structures (Lao Ping
Tong) had been prospected by shallow underground workings. Geological
and geophysical investigations of the Lao Ping Tong area by the Inner
Mongolian Geological Bureau and the China Academy of Sciences proposed
that the fault system may be underlain by intrusives at shallow depth.
In 2008, KSO undertook detailed mapping,
geophysical surveys, surface sampling and drill testing of two fault
zones in the Lao Ping Tong area. The presence of widespread
quartz-sericite-pyrite alteration with Pb/Zn mineralisation and
porphyry-style veining in each hole provided strong evidence of a nearby
mineralised porphyry intrusive.
In 2009, it drilled 6 diamond holes the
second of which discovered a Cu-Mo mineralised intrusive plug at what
was to become the Whitehorse prospect approximately 1km northeast of Lao
Ping Tong. Three of the four subsequent holes in the same vicinity
intersected strongly quartz-sericite-pyrite-clay altered granitic
porphyry rocks under tens of metres of colluvium and drifting sand cover
and varying thicknesses of equally strongly altered felsic volcanics
rocks. Anomalous Cu ± Mo values occasionally exceeding 1,000ppm Cu and
200ppm Mo occurred throughout the intrusive intercepts and
intermittently anomalous Au, Ag and As values were noted in the wallrock
Through 2010 a further 7 diamond
drill-holes established a roughly circular 700m diameter geometry for
the multi-phase Whitehorse intrusive. It also established that
anomalous Cu-Mo values were restricted to the intrusive rocks whereas
locally strong Pb-Zn mineralisation occurred both within and peripheral
to the intrusive. Significant Ag mineralisation was found in veins
traversing and peripheral to the intrusive. Petrographic studies on
the core further established that the phyllic alteration encountered
throughout each drill-hole into the intrusive body, represented a late
stage alteration over-print of an earlier Cu-Mo mineralised potassic
alteration phase. This is consistent with classic porphyry Cu deposit
models that predict the prime target zone (potassic zone) to occur at
depth underneath the phyllic zone. Chalcopyrite-mineralised (i.e.
Copper) potassic altered clasts from breccia dykes encountered in the
drill-holes support application of this model at Whitehorse and deeper
drill-holes are to be undertaken through 2011.
Also in 2010, in response to discovery of
precious and base metal anomalies, intrusive rocks and alteration in
scattered outcrops up to several kilometres from Whitehorse, KSO
conducted a project-wide high resolution magnetic survey. The results
exceeded all expectations defining not only a series of major structural
controls but also a number of Whitehorse magnetic profile look-alikes
that together with surface anomalies have produced seven new
altered-intrusive-porphyry drill targets. In addition the survey has
indicated a large underlying parent intrusive body that may also be
altered and mineralised.
Ongoing exploration will be aimed at both investigating the
Whitehorse system at depth and scout drilling the other potential
intrusive porphyry targets.