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ASX ANNOUNCEMENT/MEDIA RELEASE
29th September 2008
PRAIRIE DOWNS & WARRAMBOO
POTENTIAL FOR SUBSTANTIAL IRON ORE DEPOSITS
__________________________________________________________________
PILBARA - IRON ORE AND BASE METALS PROJECTS
Following desk top studies and research, Dynasty recently completed a field
reconnaissance on its Prairie Downs and Warramboo tenements in Western Australia and
obtained results from chip samples which confirmed the potential for substantial deposits
of iron ore. Results of up to 45.6% Fe1 were returned from a Potential CHANNEL IRON
DEPOSITS at Warramboo and up to 62.6% Fe was returned from a conglomerate at Prarie
Downs.
The purpose of the expedition is consistent with Dynasty’s aim to determine the potential
for substantial iron ore deposits in its Pilbara tenements. The field work was successful in
identifying substantial iron ore targets which are worthy of further detailed follow-up
exploration.
WARRAMBOO
Location
The Warramboo tenements cover an area of 159.5km2 and are located in the Pilbara on Red Hill
station ~100km east of the Western Australian coastal township of Onslow, 50km south of the rail
head at Robe River and 200km to the west-north-west the township of Paraburdoo, see Figure 1.
Figure 1 - Location of Iron Ore Projects
1 Fe = iron
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Geology
The Geology at Warramboo is dominated by Proterozoic arenites, shales and siltstones of the
Ashburton formation, with valleys covered in recent alluvium. In the south of the tenements,
sandstones and conglomerates of the Mount Minnie Group, strongly lateritised in parts, are
present. Tertiary pisolite and conglomerate deposits within paleochannels are also present within
the area. These deposits are referred to as “Channel Iron Deposits”.
Dynasty’s mineral exploration targets are the Channel Iron Deposit’s which are currently mined at
Rio Tinto’s Robe River, see Figure 1 approximately 60km from Warramboo and which are present
on adjacent tenements held by Mineralogy Limited.
Copper mineralisation to the south of the area appears to be related to NNW shears within the
Ashburton Formation sediments.
Figure 2 - Geology and Tenement Location Warramboo
Exploration and Project Summary
The primary target on the Warramboo tenements is iron ore concentrated in paleochannels
comprising Tertiary Pisolite2, referred to as Channel Iron Deposits.
2 A pisolite is a sedimentary rock formed from pisoliths which are concretions spherical in shape, and comprise concentric layers
reaching 5-8 mm in diameter. The name derives from the Hellenic word for pea.
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Base metals mineralisation (copper, lead and zinc) associated with shear zones is a secondary
target.
Previous exploration within the Dynasty Tenements consisted of regional geophysics and
geological mapping. Surface exploration by CRA over an area of Tertiary pisolitic conglomerate
covered by Dynasty tenements, returned several results in the 50-60% Fe range which shows
good potential for Channel Iron Deposits.
Dynasty also collected several rock chip samples of the Channel Iron Deposits on the western
edge of E 08/1620 South (see Figure 2) with the results presented in Table 1. The Strongest
result was 45.6% Fe from this outcrop
Table 1 - Selected Rock-chip results Warramboo Downs
Sample Locality Description Al2O3 Fe P S SiO2
611
Warramboo - North of
Mineralogy CID Ironstone, Ashbuton Formation siltstones. 6.69 37.8 0.642 0.051 25.8
612 Warramboo South Goethite Rich Pisolite conglomerate 2.41 31.2 0.022 0.012 44.8
613 Warramboo South Tertiary Pisolitic conglomerate CID 3.73 45.6 0.032 0.067 19.1
614 Warramboo South Tertiary Pisolitic conglomerate CID 2.87 36.6 0.03 0.044 35
615 Warramboo South Tertiary Pisolitic conglomerate CID 1.71 35.3 0.035 0.044 38.9
Airborne radiometrics indicates there may be extensions of the Channel Iron Deposits under cover
and with a potential length within the Dynasty tenements of 3km and width of around 800m, see
Figure 3. Without drilling it is not possible to determine the depth (or thickness) of any Channel
Iron Deposits. However, typically these deposits in the Pilbara range in thickness from 5m to 50m.
Figure 3 – Photograph Warramboo Sub-crop
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Future Exploration
Future programs will consist of gravity surveys, ground radiometrics and mapping, followed by
targeted drilling to determine the length, depth and grade of potential Channel Iron Deposits in the
paleochannels.
PRAIRIE DOWNS
Location
The Prairie Downs tenements cover an area of ~1390km2 located ~30km west of the rail head at
Mt Newman (see Figure 1).
Geology
The geology of the area consists of the complex Hamersley formation which contains Brockman
and Marra Mamba Iron Formations, see Figure 4 as well as an older unnamed iron formation.
Brockman and Marra Mamba Iron Formations are mined at Mt Newman, Mt Whaleback, Mt Tom
Price, Brockmans and other mines
Figure 4 - Typical, Hamersley Basin Stratigraphy
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The Prairie Downs Fault cuts the tenement in a north westerly direction and separates the
Hamersley formation from Bangemall Basin sediments, see Figure 5. These sediments have a
coarse basal conglomerate consisting mainly of clasts of Hamersley iron formation rocks, or their
equivalent. Iron, gold and copper mineralisation is present in the region.
Figure 5 – Geology and Prairie Downs Tenements
Exploration and Project Summary
Dynasty’s priority target on Prairie Downs is a commercially viable deposit of Brockman and/or
Marra Mamba Iron Formation. A secondary target is paleochannel iron deposits and a lower
priority target is gold, base metals (copper, silver, lead and zinc) and uranium mineralisation.
Previous exploration within the Dynasty Tenements included some work on the Hamersley Iron
formation in the north as well as regional surveys for gold and base metals in the south.
Dynasty has recently completed a reconnaissance trip where several rock chip samples from three
areas were taken with the results presented in Table 2.
Table 2 - Selected Rock-chip results Prairie Downs
Sample Locality Description Al2O3 Fe P S SiO2
617
North East
Prarie
Downs
Banded Iron Formation with some Bedded Iron
Formation, MGT, Haem and Silica 0.30 42.9 0.077 0.025 35.7
618
Central
Prarie
Downs
Conglomerate with Hamersley Formation clasts of BIF
and Chert within a Haematite/silica matrix 0.38 48.5 0.060 0.018 29.9
619
Central
Prarie Conglomerate as above, more Cherty 0.45 36.9 0.034 0.026 46.5
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Downs
620
Central
Prarie
Downs
Conglomerate, dominated by Iron Formation clasts and
strongly Haematitic matrix 1.84 62.6 0.031 0.010 7.8
622
Central
Prarie
Downs Conglomerate, around 50% Chert, 50% BIF clasts 0.20 29.8 0.064 0.007 56.5
The Dynasty tenements cover the Brockman and Marra Mamba formations and an un-named iron
formation. In the north east of the tenement, an enriched iron outcrop in which siliceous layers of
the original banded iron formation had been partially replaced by haematite/martite, was examined
and sampled, see results Table 2.
The Geology map shows the iron formation forming a large syncline with the central part of the
syncline located to the north of the DMA tenement. The magnetics, see Figure 6, shows that a
substantial portion of the iron formation may cross into the Dynasty’s tenements.
Figure 6 - North East Prarie Downs Project, Aeromagnetics
Field observations in the central part of the project of the basal conglomerate of the Prarie Downs
Formation, within the Bangemall Basin, shows it to contain zones of high Iron formation content
with large clasts of Hamersley Iron Formation or equivalent within a ferruginous (haematitic)
matrix. Results shown in Table 2 are of this conglomerate.
The results of up to 62.6% Fe with low contaminants are highly encouraging. The variation of the
clast content and the silica content in the haematite matrix are responsible for the variation in Fe
content. Higher in the stratigraphy the chert clast content is significantly higher hence the lower Fe
response. The higher grade outcrops may be related to structural controls or a particular horizon
and further work is needed to clarify this.
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Figure 7 – Outcrop Tertiary Pisolite – Prairie Downs
This formation is mapped to have a large areal extent with dimensions of several kilometres and a
depth and thickness of the higher grade material as yet unknown. Based on the observations to
date, this basal conglomerate has the potential to contain a substantial iron deposit.
East of Dynasty’s Prairie Downs’ tenements there is a silver-lead-zinc deposit owned by Prairie
Downs Metals Limited which has reported it to contain 4.7 million tonnes at 6.3% zinc, 18g/t silver
and 1.8% lead.
From limited published geological data on the project, it appears this mineralisation is partly
controlled by the Prairie Downs Fault which cuts through the Dynasty tenements and represents a
target for further investigation.
Copper reported on a major north east structure in the south of the tenement may be part of a
larger system in a dolomitic siltstone unit which could represent a host for more significant
mineralisation. Samples from this copper mineralisation returned 29.1% copper and 20.9g/t silver.
The region could also contain significant Uranium mineralisation in calcrete or as a paleochannel
deposit with uranium sourced from the granites to the east.
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Future Exploration
Results from the recent reconnaissance trip will be evaluated and a ground magnetic survey in the
north will be completed. Targets for high grade Bedded Iron Formation will be identified and
drilled. The Iron rich conglomerate will be mapped and sampled and if encouraging further work
such as ground magnetics and drilling will be completed. Prospecting of the copper occurrences
will be followed by detailed mapping and soil sampling to identify drill targets.
By order of the Board
Malcolm Carson
Technical Director
For further information please contact either Messrs:
Malcolm Carson (Technical Director) on 0417692849
Lewis Tay (Executive Director) on 0433166818
Richard Oh (Chairman) on 0411697249
Qualifying statement
Malcolm Carson has compiled the information in this report from information supplied by Dynasty Metals Limited.
Malcolm Carson has sufficient experience that is relevant to the style of mineralisation and type of deposit under
consideration and to the activity that he is undertaking to qualify as a Competent Person as defined in the 2004 Edition
of the Australasian Code for Reporting of Exploration Results. Mr Carson consents to the inclusion in the report of the
matters based on his information in the form and context in which it appears.
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