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Vangold
Resources Conducts Aerial Survey over Rwanda
11-17-2008
The aerial survey for
the measurement of the earth's gravity and magnetic fields over Lake Kivu and
South West of Rwanda has been concluded. A total of 2,088 line km has been flown
against 3,100 km planned, linearly achieving 70% coverage of the East Kivu
Graben. The apparent lack of completion of the planned survey is primarily due
to political unrest in the Democratic Republic of Congo region, despite the best
efforts from the Rwandan side and Vangold.
Despite this difficulty, the
contractor, South African based New ResolutionGeophysics ("NRG"), was able to
complete 100% of the southern survey covering Block 2 and 100% of Block 4 over
Lake Kivu.
Additionally NRG was able to achieve important coverage of the east-west flight
lines over Block1, and the southern and northern regions of the East Kivu Graben.
The flight line coverage in Block 1 traverses across the dip geometry of theEast
Kivu Graben in the Northern area and Southern areas that mitigates border areas
not covered.
The data quality is good, having
met all survey and contractual specifications. The geological and geophysical
objectives of covering the whole of
Rwanda concession area have been partially met in Block 1,
and100% accomplished in the Block 2 survey areas. Further, gravity and magnetic
data 5 km from the border with DRC in the northern lake area has not been
collected as it was within the turning area of the airplane. Thisis however,
mitigated by two east-west dip flight lines that cross the northern area and a
further three lines in the southern part of the Lake.
The sedimentary basin development
cannot be directly adduced from raw field data. The data needs topographical
corrections in the rugged mountains/hills in the south and the bathymetry
corrections of the water depth in the lake. Therefore, computer data room
processing of the raw field data in
Johannesburg has just been completed by NRG. In Toronto,
Vangold's consultant, PGW, have embarked on interpretation and modeling of the
data. In-house processing and interpretation by Vangold's geotechnical team is
also currently in progress. Both work programs will be merged and integrated
with the 1981 aeromagnetic survey data, and previously conducted ground gravity
surveys. The expected result will be a depth and area model of the sedimentary
basin in East Kivu Graben. This will be integrated with geology, ASAR study and
geochemical data recently gathered from Rubona gasgeochemical gas study for the
evaluation of the hydrocarbon prospectively of Lake Kivu.
In Uganda
Vangold currently holds more than
2,200 square kilometers in exploration licenses in
Uganda that are grouped into 6 projects:
Kafunjo (Ni, Cu, Pt),West Nile (Au), Kilembe (Cu, Co), Kamwenge (Cu, Au),Fort
Portal (Cu, Au) and Bugiri (Au). Vangold's website lists the current status,
work completed to date, and proposed work programs for each of these exciting
areas.
Current exploration work on the Ugandan mineral
properties involves continued geological mapping and prospecting of concessions,
including newly acquired licenses in West Nile, and soil geochemistry across
highly prospective zones at West Nile (Kilo-Moto style host rocks),
Bugiri(Banded Iron-Formations or BIFs) in Lake Victoria Greenstone Gold Belt and
Kafunjo (Kabanga-style nickel sulphide potential) to delineate high potential
mineral targets. The Ugandan team consists of national geologists and local
laborers. Work is overseen by Danae A. Voormeij,M.Sc., P. Geo. QP under NI
43-101 and VP of Exploration for Vangold.
Kafunjo Drill Program
Phase 1 Drill Program Completed
* Vangold Resources Ltd. holds three adjacent licences
which are located in southwest Uganda near the triple junction of Tanzania,
Rwanda, and Uganda. At Kafunjo strong coincident low magnetic and high gravity
anomalies occur on a magnetic trend which arcsfrom the ultramafic-hosted nickel-PGM
deposits at Kabanga and Kagera inTanzania. Similarities to the local geology and
low magnetic anomalies at the Kabanga deposit strongly suggest that the
anomalies at Kafunjo may becaused by an ultramafic body.
* A diamond drilling program, planned to test the central
sector of a 4 kmby 1 km anomalous zone at Kafunjo to depths of approximately 700
to 1000metres (m) has been completed. A total of 2,317 m was cored in three
holes. The three drill holes did not locate potentially economic mineralization.
Ultramafic rocks were not intersected in Phase 1.
* The drill is now being demobilized and the site
recontoured.
* Each of three holes crossed metasedimentary mica schist
and siltymudstone. Sedimentary facies appear to change rapidly: cross bedding,
scourchannels, and soft-sediment slumps mark stratigraphic
disruptions.Concordant metasedimentary graphite-pyrrhotite iron formation occurs
intrue widths of 30-40 m, with maximum pyrrhotite concentration of 10%
inintervals of several metres. Occasional specks of chalcopyrite occur on
themargins of pyrrhotite bands. Occasional kink folds indicate positions onfold
limbs. Fracturing on bedding/foliation creates blocky zones ofdifficult
drilling. Transcurrent faults are interpreted as both steeply and flat dipping.
A potential host for nickel sulphide mineralization was not encountered.
* A ground magnetic survey was completed in early 2007 by
personnel from the Geophysical Department of the Uganda Geological Survey in
order toverify the results of previous surveys. The position and intensity of
the magnetic low corresponds to the earlier information. Modelling of the
magnetic low by various geophysicists has suggested the upper portion of the
anomaly to be between 200 and 600 m below surface. The quantities of pyrrhotite
which are present do not account for the intensity of the magnetic anomaly.
* In June 2008, a gravity survey was completed by a field
crew from Kenya General Electricity ("KenGen"). A depth model of the gravity
anomaly prepared by a geophysicist of KenGen showsa flat-lying dense body, with
an upper surface 700 to 1,200 m below surface, extending 950 m in width
northeast-southwest, 750-1250 m invertical thickness, and with a flat to
moderate northeasterly dip on bothupper and lower surfaces. The specific gravity
("SG") of the dense body is estimated by the geophysicist to be 3.4 grams/cubic
centimeter (g/cc), in comparison to a SG of 2.55-2.70 g/cc of the enclosing
metasedimentaryrocks.
* A SG test of 1.0 m of core from 655.75 to 656.75 m in
hole K-03-08 of pyrrhotite iron formation was performed by a technician in the
laboratoryof the Geological Survey of Uganda. The core is representative of the
highest average quantity of pyrrhotite in the hole and generally in all of the
drilling, visually estimated at 10%. The SG is determined by the difference in
weight in air and weight while immersed in water to be 2.90 g/cc. This compares
with a first approximation calculation which substituted 10% of mica schist (SG
2.70 g/cc) by 10% of pyrrhotite(SG 3.65 g/cc), to arrive at a SG of 2.89 g/cc.
The quantities of pyrrhotite that have been intersected do not explain the
gravity high.
* The geophysical anomalies indicate the presence of a
large, dense, and intensely magnetic body.
* The first hole, K-01-08, was drilled to 943 m prior to
the collection and interpretation of gravity data. It was sited over the
magnetic low, and as later determined is above the central portion of the
gravity anomaly. At this location the top of the dense body is shown to be
approximately 1,000 m below surface, and thus the hole may have been short of
the target.
* K-02-08 was positioned to cross the centre of the
gravity anomaly at approximately 700 m below surface and to continue to cross
the magnetic low at approximately 1,000 m. The hole was ended at a length of 635
m because of caving of wall rocks.
* K-03-08 was drilled above the south central part of the
gravity anomaly, oriented to enter the upper surface of the gravity profile at
approximately700 m below surface, and to continue to cross the magnetic anomaly
at approximately 1,050 m. The vicinity of the gravity target was entered at
approximately 680 m below surface. Walls of the hole began to cave and drilling
had to be terminated at 739 m in the hole. Silty iron formation from 610-700 m
in the hole contains the mineral chiastolite (and alusite) and small sheared
fragments of garnetite, both of which indicate a slightly higher grade of
metamorphism and are known to be present in the metasediments at Kabanga.
* Samples taken at regularly spaced intervals of the
drill core will be analyzed geochemically for multiple elements. A 3-dimensional
plot of values may indicate new or refined target locations.
* All core from the Kafunjo
project, including the 1995 core from the first phase of drilling, will be
stored at the Geological Survey in
Entebbe. A storage container on cement pillars will house core
for convenient future reference.
* Airborne geophysical surveys were funded by
international monetary banking sources coordinated through the Geological Survey
of Uganda. During 2007 and 2008, airborne surveys flown covered a majority of
Uganda including areas where Vangold holds licences. The program consists
of700,000 line kilometers of magnetic and radiometric data collection, with
selected high potential areas flown by helicopter and fixed wing aircraftfor
advanced electromagnetics. Flights over the Kafunjo licences during August and
September 2008 included all three geophysical sensors. When the data is made
available Vangold will acquire the CDs and commission services for
interpretation.
* Future programs may include
reinterpretation of the gravity model with incorporation of drill hole data,
inspection of the new airborne surveys,and compilation of lithology and
geochemistry into a 3-D model. Reversecirculation drilling, which is more able
to complete holes in broken rock formations, may be considered for a subsequent
program; equipment which can drill to +700 m is available in
Tanzania.
* Dal Brynelsen, President and CEO
of Vangold states, "Kafunjo continues to be an exciting project with good
potential for a world-class nickel-sulfide deposit. Our team remains on the
ground in Uganda and
our exploration efforts carry on. Once the core is interpreted and assays are
received, Vangold's geological team will determine the next appropriate step(s)."
Kenya, Blocks 3A &
3B Update
Chevron previously shot seismic
data (1975) which was forwarded from
the irIron Mountain storage site (Houston)
to seismic processing company SensorGeophysical, Calgary ("Sensor").
Reprocessing of the data, estimated to be completed on or about November 30,
2008, will result in better definition and structural control of the regional
Cretaceous play. At Block 3, 11prospects/leads were identified through
interpretation of Chevron (1975)seismic data along with integration and
interpretation reviews of Amoco(1986), Total (1990), Beicip (1980, 1984),
Western InternationalAtlas/CORELAB (1994), and AIconsult (1998).
The probabilistic productive areas
covered by Vangold's prospects range from 4713 to 37,498 acres with an average
of 21,000 acres and aggregating to 202,025 acres. Evidence of a working
petroleum system in Block 3A,which forms part of the Anza Graben Basin, are oil
shows in Sirus-1 well (drilled by Amoco in Block 10 A), Lundin Petroleum AB ("Lundin").
Block10A lies to the northeast of Block 3A. China National Oil Company, (CNOOCs)
Block 9 lies in between Block 10A and Block 3A. All are situated in the
Anza Graben Basin.
The gross unrisked prospective
resources estimate in Block 3 are beingevaluated in house by our Geotechnical
Team with parameters being derived/estimated from the look-alike
Melut Basin in Southern Sudan (the
largest oil field in the Melut Basin is the Great Palogue Field with estimated
reserves of 900 million barrels).
Lundin reported they completed an aerogravity survey over
Block 10 A, and have targeted one exploratory well to be drilled at the Bogal
Prospect, Block 9, in the first quarter 2009. The Bogal prospect in Block 9 is
120km from Vangold's Block 3.
Preliminary reprocessing of two seismic lines over Blocks
3A and 3B show stacked, amplitude anomalies on one structural prospect. AVO
analysis on one seismic line by Sensor further appears to show three P Wave
Impedance and Fluid Factor anomalies that may further lower the perceived
exploration risk.
Vangold's Geotechnical team has
planned an infill seismic survey, likely to be undertaken early next year, to
incorporate longer spread lengths to optimize seismic attribute analysis and
display. Vangold's technical team acquired gravity and magnetic data from
Edcon-PRJ Gravity & Magnetics, and recently completed in-house digitization of
the same. This data will be integrated with the
Leicester gravity data, and Paterson,
Grant & Watson's ("PGW") magnetic data purchased by Vangold. Integration of all
data will be performed after Sensor Geophysical reprocesses Chevrons data at the
end of November 2008. The reprocessed data will be re-interpreted by consultants
shortly thereafter.
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