The ground EM program was conducted as a follow up to a trenching program which had previously located high-grade copper-zinc mineralisation at both Nakru 2 Northwest and Nakru 3. Trench NK19_T02 returned 11m @ 4.13% Cu, 9.04% Zn, 0.29g/t Au & 47g/t Ag, at the Nakru 2 Northwest prospect and trench NK19-T14-2B returned 6m @ 2.23% Cu, 8.23% Zn, 1.96g/t Au and 236g/t Ag, at the Nakru 3 prospect. The objective of the ground EM survey was to define targets, related to the mineralisation exposed in the trenches, for follow up drill testing.
'At Nakru 2 Northwest the ground EM defined a clear drill target 250m along strike from the high grade copper-zinc mineralisation in trench NK19_T02, which returned 11m @ 4.13% Cu and 9.04% Zn and now we can move to finalising plans for drill testing both the EM conductor and copperzinc mineralisation exposed in trench NK19_T02 at Nakru 2 Northwest' he said.
'At Nakru 3 we also have confirmed high-grade copper-zinc mineralisation which the EM data suggests is part of much larger alteration zones which potentially indicates that the mineralisation is more extensive than what has been intersected in the surface trenching.'
Nakru 2 Northwest Ground EM Geophysical Survey Results
The Nakru 2 Northwest prospect is located approximately 500m northwest of the Nakru 2 Mineral Resource, which is estimated as 6.33Mt @ 0.85% Cu, 0.04g/t Au & 2.34g/t Ag and classified as Inferred in accordance with JORC 20126 . Five trenches constructed between October-
At the Nakru 2 Northwest prospect two EM transmitter loops were used to energise the known mineralisation and readings of the EM response were taken on lines orthogonal to the long axis of the transmitter loop.
The purpose for energising the mineralisation at the Nakru 2 Northwest prospect with EM loops of two different orientations, was to ensure that the mineralisation exposed in the trenches was effectively energised if the mineralisation was steeply dipping and striking northeast or if the mineralisation was shallowly dipping to the northeast and striking northwest.
From
From
Nakru 3 Ground EM Geophysical Survey Results
The Nakru 3 prospect is located approximately 800m north-east of the Nakru 1 Inferred Mineral Resource and 2.3km east of the Nakru 2 North-West prospect. Historical surface geochemistry sampling at Nakru 3 showed several areas with elevated Cu and Zn values which provided the encouragement to proceed with a trenching program at Nakru 3. Fourteen trenches for a total of 835m were constructed in the general area around the Nakru 3 during October-
Trenches NK19_T14_2B, NK19_T12_2 and NK19_T12_3 exposed copper-zinc-gold-silver mineralisation, within exposed pyrite-silica-clay alteration zones and extensive quartz stockwork veining. The area of alteration extends beyond the limits of the area which was trenched. The thickest and highest-grade copper-zinc-gold-silver mineralisation at Nakru 3 was exposed in trench NK19-T14_2B which returned 6m @ 2.23% Cu, 8.23% Zn, 1.96g/t Au and 236g/t Ag8 . The massive sulphide copper-zinc mineralisation occurs within consistent zones of steeply dipping silica-rich rhyodacite breccias containing disseminated sulphides. The mineralisation located to date can be generally described as a combination of structurally controlled and 'stratabound' hydrothermal felsic breccia with polyphase quartz stockwork mineralisation. Alteration is dominated by silicaclay-pyrite with commonly disseminated copper and zinc sulphides.
As the strike of the mineralisation at Nakru 3 was thought to be generally to the north - northeast, a single EM transmitter loop was used to energise the known mineralisation. The transmitter loop was orientated with its long axis north-south and EM readings were collected on lines orientated east-west. The EM reading lines were spaced 100m apart and readings were taken at 25-50m station spacings along the lines. The X, Y and Z components of the secondary EM response were recorded at each station spacing.
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Summary of Ground EM Geophysical Survey Results from Nakru 2 Northwest and Nakru 3
At the Nakru 2 Northwest prospect the causative source of an EM anomaly on line 5500N, is interpreted to be a plate like conductor at a depth of approximately 110m, of moderate conductivity, 120m x 120m in dimensions and dipping at 20 degrees northeast. This conductor occurs 250m north, along strike and down plunge of an intersection of high-grade copper-zinc mineralisation in Trench NK19_T03 which returned 11m @ 4.13% Cu & 9.04% Zn. The plate conductor represents a clearly defined quality drill target which could be tested with a 200m deep drill hole. At the Nakru 3 prospect two large alterations zones are interpreted from the ground EM data in the west and east of the prospect area. These two zones suggest that the massive copper-zinc mineralisation exposed in trenches at Nakru 3, could potentially be part of a larger mineralised system. Authorised on behalf of
Contact:
Dr.
Managing Director
Email: wfhuang@coppermoly.com.au
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