Technical Director Comment
Mr
'The shallow Exploration Target at the
'The closest analogy to the Earaheedy unconformity related sandstone hosted Zn Pb style is the large Paroo Pb deposit (120km SW of Earaheedy). The Paroo deposit is an oxidized system located in the same formation as Earaheedy. Earaheedy is a sulphide matrix replacement style with simple metallurgical characteristics'
The potential quantity and grade of the Exploration Target is conceptual in nature, there has been insufficient exploration to estimate a Mineral Resource and it is uncertain if further exploration will result in the estimation of a Mineral Resource. Refer further detail on page 6 of this announcement in respect of the Exploration Target.
RC Drilling Programme Completed by Rumble
The RC drilling programme comprised of 19 drill holes (1518m total) targeting the interpreted up-dip position of the prospective unconformity related basal sandstone sub-basin. No previous drilling has tested this position. The two areas tested are some 10km apart. The drilling tested along strike on 500m hole spacing. To aid with targeting (shallow cover - to 5m), recent passive seismic survey traverses, completed by Rumble, were used to target the inferred surface expression of the prospective sandstone unit. Drill holes were vertical, ranging from 60 to 108m depth. Assaying (wet analysis) was based on systematic on-site pXRF assaying of the RC drill hole cuttings. If the pXRF response was >1000ppm Zn, the sample(s) was submitted for four acid digest multi-element analysis.
Results
The current RC drilling has defined two areas of significant Zn Pb mineralisation, Chinook and Magazine, associated with flat to slightly northeast dipping sandstone units. The sandstone units are the basal unconformity to the overlying Frere Iron Formation. Note that all mineralisation defined at Earaheedy is blind.
Chinook Prospect
Three RC drill holes drilled 500m apart returned significant flat lying Zn - Pb with Ag mineralisation.
EHRC019 - 11m @ 3.35% Zn, 0.78% Pb, 12.78 g/t Ag (4.13% Zn + Pb) from 61m within a broader zone of 22m @ 2.04% Zn, 0.48% Pb (2.52% Zn + Pb) from 53m
EHRC018 - 5m @ 1.68% Zn, 0.15% Pb (1.83% Zn + Pb) from 72m
EHRC020 - 12m @ 0.48% Zn, 0.72% Pb, 1.4 g/t Ag (1.2% Zn + Pb) from 43m
Drilling has defined strong continuity of flat lying mineralisation over 1000m of strike and in association with historic drilling has demonstrated strong continuity normal to strike. Historic RC drill holes TRC65 and TRC70 returned very significant mineralisation.
TRC65 - 7m @ 3.57% Zn + Pb from 60m.
TRC70 - 5m @ 3.55% Zn + Pb from 126m to EOH (note EOH assay of 6.18% Zn + Pb)
Section AA (image 3 & 4) highlights very strong continuity (approximately normal to strike) over a distance of 815m (completely open). The depth to mineralisation at drill hole EHRC019 is 60m. It is interpreted that the very shallow northeast dip of the Yelma and Frere Iron Formations has flattened towards the southwest. This upgrades the potential for mineralisation to extend further southwest ('up-dip').
Section AA (image 4) presents the assays for EHRC019 and demonstrates that the mineralisation envelope is up to 22m wide (true width) in sandstone and highlights the consistent nature of the zinc and silver mineralisation. Visually, sphalerite, galena and pyrite have replaced the matrix within coarse sandstone.
The Chinook prospect is completely open northwest and southeast along strike. Also, the prospect is completely open up-dip and very limited drilling has been completed down-dip
Magazine Prospect (image 5)
A total of sixteen (16) holes were completed over a strike of approximately 5km within the southeast portion of E69/3464. Eight (8) holes intercepted Zn Pb mineralisation in the northern portion of the area tested (Magazine Prospect). The remaining eight (8) holes were drilled too far to the southwest and intercepted the lower purple shale (below the unconformity) indicating the prospective sandstone unit contact is to the northeast.
The Magazine Prospect is completely open along strike to the northwest. Some 10km of untested strike lies between the Chinook and Magazine prospects. The Magazine Prospect is also open updip and southeast along strike.
Exploration Target
Rumble's Zn-Pb Exploration Target at the
The Exploration Target has been estimated in order to provide an assessment of the potential for largescale Zn-Pb deposits within the
The Exploration Target is based on the current geological understanding of the mineralisation geometry, continuity of mineralisation and regional geology. This understanding is provided by an extensive drill hole database, regional mapping, coupled with understanding of the host stratigraphic sequence and a feasibility study completed at the nearby Paroo Pb deposit.
Included in the data on which this Exploration Target has been prepared is recent RC drilling of 21 holes for 1892m (two RC stages) and
Drilling results have demonstrated strong continuity of shallow, flat lying mineralisation; Over 20km's of prospective strike and open (refer image 2); Minimum 800m of width (based on shallow 7.5-degree and shallow depth to 80m, based on drilling results. Example is shown in image 4 - strike continuity normal to strike; o True width of mineralisation of 7metres based on average true width received in drilling results and Specific gravity (SG) of 2.5 (world average SG of sandstone - not accounting for metal).
The Company intends to test the Exploration Target with drilling and this further drilling is expected to extend over approximately 12 months. Grade ranges have been either estimated or assigned from lower and upper grades of mineralisation received in drilling results. A classification is not applicable for an Exploration Target.
Regional Comparative
The Earaheedy Pb-Zn sandstone hosted mineralisation has similarities with the
The Paroo Pb deposit is a large supergene (predominantly Pb carbonate) deposit under shallow cover. The Earaheedy project is a sulphide system (based on work to date) and is geologically equivalent (temporally and spatially with respect to stratigraphy) to the Paroo Pb mineralisation. Some dimensions of the Paroo Pb deposit include:
Magellan - 1600m by 900m by 12m width of mineralisation;
Cano - 850m by 430m by 7m width of mineralisation;
Pinzon - 1000m by 200m by 5m width of mineralisation and Cover is up to 25m
Next Steps
RC drilling following up the Chinook and Magazine discoveries and Broad spaced RC drilling to scope the 20km's of potential strike, and working toward confirming the Exploration Target
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