RED ROCK RESOURCES PLC
Kenya: two copper targets to be drilled at Migori
Dated: 13 December 2010
Red Rock Resources Plc ("Red Rock" or the "Company"), an exploration and mining company with gold projects in Kenya, Costa Rica and Colombia, and investments in iron ore, manganese, uranium and rare earths, reports that it has found two significant drillable sulphide targets from analysis of results from a VTEM airborne electromagnetic survey conducted by Geotech Airborne Ltd over the historic Macalder mine in south west Kenya.
An initial programme of up to 19 drill holes and two trenches will now test these targets for copper, other base metal, gold, and silver mineralisation.
A specially modified helicopter towing a wire loop was used to conduct the survey, and flew the area at low level along flight lines 100m apart collecting multichannel electromagnetic geophysical data. The total survey comprised 278 line kilometres, flown at 50m height, over an area of approximately 25 square kilometres. Survey flight lines were flown in a NE-SW orientation, perpendicular to the regional strike of the Macalder VMS deposit geology, covering both limbs of a large scale NW-SE trending anticline.
The VTEM system measured 2 electromagnetic (EM) fields; dB/dt and B-Field (36 channels of each), along with TMI (Total Magnetic Intensity) and DTM (Digital Terrain Model) data. Several EM anomalies within the survey area were detected and the two priority targets have been identified in the late channel 33 B-field EM grid image (Figure 1) as Conductor 1 and Conductor 2. Due to a large number of culturally induced anomalies, the Macalder town and other cultural sites (ie power line transformers and metal bridges) have been excised from the survey area.
Figure 1 : AEM B-Field channel 33 grid, showing two priority conductors and CDI section lines
http://www.rns-pdf.londonstockexchange.com/rns/8254X_2-2010-12-13.pdf
AEM Conductivity Depth Sections
Multichannel electromagnetic profile data measured by the AEM system can be mathematically processed into apparent conductivity depth sections. The two priority targets Conductivity Depth Images (CDI) sections were produced by the contractor and the CDI colour displays high conductivity zones as red, and low conductivity zones (resistive) as blue.
The first CDI section (Figure 2) is across the Macalder volcanic massive sulphide (VMS) deposit and demonstrates that the conductor is just below the surface on flight line 27. The Macalder conductor is measured strongly over 3 flight lines, and plunges east at depth across another 2 flight lines. The area directly below the main open cut pit to the west of this conductor does not have a strong conductive response, because the ore has been depleted in the underground to more than 200m depth.
Figure 2
http://www.rns-pdf.londonstockexchange.com/rns/8254X_-2010-12-13.pdf
The second CDI section (Figure 3) measures the edge of a new sulphide target identified as Conductor 2. This conductor is not outcropping and covered with soil; however traces of Gossanous BIFs (Banded Iron Formations) in soil float were located in close proximity to this target. Conductor 2 is measured strongly over 2 flight lines and plunges to the south east over another 3 flight lines. There are also sulphidic graphitic schists mapped in the area, so this conductive anomaly may not be related to base metals sulphide mineralisation, although it is similar in strength to Conductor 1.
Figure 3
http://www.rns-pdf.londonstockexchange.com/rns/8254X_1-2010-12-13.pdf
Conductor 2 is located on the eastern side of the district scale North - South trending fault which Macalder is thought to be intruded along, and related to. The location of conductor 2 adjacent to mapped BIFs, and having a coincident magnetic anomaly, requires drill testing to locate the geological source of the geophysical response.
Proposed RC Drilling
Conductor 1 is located directly east of the main Macalder open cut pit and underground workings with the AEM Channel 33 point and gridded data shown in Figure 4. There is potential for sulphide ore immediately north of, and directly below the eastern open cut pit dipping steeply to the north. The CDI sections suggest the mineralisation is close to the surface; however a 3D conductor plate model will be completed early in 2011 to finalise the collar locations.
An eastern lode position at Macalder may have been overlooked in the previous (1950-1966) surface and underground drill programs, however historic drilling data has been lost in the 1960s so only historic mine sections showing drilling and ore positions remain. A preliminary drill program has been designed to test the Macalder conductor (Figure 5), with the drilling of angled holes to the south west as indicated. The centre of the conductor will be drilled first with 3 holes across the strike, prior to the other drill holes along strike if warranted.
A second strong conductor has been located south west of the Macalder open cut, however it is directly under the mill ruins so may be a culturally induced EM anomaly, caused by remaining metal infrastructure including floatation tanks as seen on the satellite image. A single hole will be drilled under the old mill area to ensure this response is not from a sulphide source under the mill.
Figure 4: B-Field AEM line and gridded data from channel 33 display the location of the conductors
http://www.rns-pdf.londonstockexchange.com/rns/8254X_3-2010-12-13.pdf
Figure 5: Proposed RC drill holes focusing on the area north and under the eastern open cut pit
http://www.rns-pdf.londonstockexchange.com/rns/8254X_4-2010-12-13.pdf
Six drill holes have been proposed to test Conductor 2, as the partial AEM measurement will make 3D EM plate modelling un-reliable. Two trenches are currently in progress across this target area to map the stratigraphy dip, prior to finalising the drill collar locations and drill azimuths.
Comment
Andrew Bell, CEO of Red Rock, comments "The Macalder mine produced good grades of copper and gold, and was also rich in zinc, silver and cobalt. The first target looks like a strong prospect for extension of that mineralisation, while the second looks like a possible repetition on the edge of the next anticline in the fold system. We know what we want to find out with the initial programmes. The key to the first target will be size; the key to the second will be whether it is a base metal sulphide."
Competent Person Statement
The technical information in this report relates to exploration results based on information compiled by consultant Mr. Grant Donnes, who is a Member of the Australian Institute of Geoscientists (AIG) and Australian Society of Exploration Geophysicists (ASEG). Mr. Donnes has sufficient experience in the style of mineralisation and type of deposit under consideration. Mr. Donnes consents to the inclusion in this announcement of the matters based on his information in the form and context in which it appears. Mr Donnes is a self-employed consultant to the Company.
Enquiries:
Andrew Bell |
0207 402 4580 or 07766 474849
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Red Rock Resources plc |
Chairman
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Sandra Spencer |
0207 402 4580 or 07757 660 798
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Red Rock Resources plc |
Public and Investor Relations |
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Peter Trevelyan-Clark/ Ben Jeynes
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020 7444 0800 |
Religare Capital Markets |
Nominated Adviser |
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Nick Emerson |
01483 413500 |
Simple Investments Ltd |
Broker |
Updates on the Company's activities are regularly posted on its website, www.rrrplc.com.