Follow up exploration is in progress at four recently identified priority prospects for large porphyry copper-gold deposits at
The prospects were identified from recent reconnaissance field checking, new rock chip assays reported here for the first time and interpretation of regional magnetic data. This work was prompted by the recent discovery of significant porphyry copper-gold mineralisation at Boda by
At Boda, which lies immediately along trend from Impact's Boda South target, a significant intercept of 502 m at 0.48 g/t gold and 0.20% copper was returned which included a higher grade 'core' of 108 metres at 1.06 g/t gold and 0.41% copper.
Alkane's announcement reveals the gold-copper mineralisation and related alteration minerals are strongly zoned adjacent to, and within, the parent porphyry intrusion, called the
FOUR PRIORITY PROSPECTS
The four prospects identified are Boda South, Greenobbys, Apsley and
The Boda South target is the highest priority area as it lies immediately along trend to the south of the Boda discovery. It has not been explored because it is partly covered by thin alluvial cover. The regional magnetic data suggests that the southern end of the Boda-Kaiser intrusive complex extends onto Impact's ground for up to at least 500 metres where it is then truncated by the Nindethanna Thrust, a major deep-seated structure that traverses much of the central part of the project area.
This thrust may have buried extensions to the Boda-Kaiser complex and related skarns which are now manifest as numerous unexplained magnetic anomalies in the target area. Field checking is now underway following recent granting of Land Access permissions
Greenobbys: This target area lies immediately east of Boda South and covers rocks of Devonian and older age characterised by a number of magnetic anomalies.
A significant gold-in-quartz vein system was previously identified by Impact in the south east corner of the target area (ASX Release
A circular strong magnetic anomaly some 300 m in diameter visible in the regional magnetic data is coincident with the Greenobbys vein and is a direct target for mineralised parent intrusion. Further field checking and geophysical modelling of the magnetic anomalies is required.
In the northern part of the Greenobbys target area field checking of part of a significant north east trending magnetic anomaly indicates the majority of the anomaly is not exposed and is covered by thin alluvium. Float (loose rock) samples of smoky to bucky quartz veins and sericite-altered felsic volcanic rocks with sulphide stringers returned assays up to 0.33 g/t gold, 4.6 g/t silver and 115 ppm molybdenum. Further detailed mapping and sampling is required and is in progress.
The Apsley target is centred 8 km south of
New rock chip assays taken by Impact returned up to 1.45 g/t gold and 7.8% copper associated with smoky quartz veins with visible copper sulphides and oxides including chalcopyrite, chalcocite, bornite, azurite, and malachite. The veins also contain the pathfinder metals molybdenum, bismuth, tellurium and tungsten.
Assays by previous explorers also returned significant assays up to 1.1 g/t gold, 5.9% copper, 25 g/t silver and 0.12% molybdenum (NSW Dept website). The magnetic data indicates the area sampled is coincident with a broad weak linear magnetic anomaly that for 2,000 metres along trend.
Several other much stronger unexplained magnetic anomalies up to 2,000 metres long are occur in the northwest of the prospect area. Negotiations for land access to this area is in progress.
NEXT STEPS
This new data has reinforced Impact's belief that its tenements in the Lachlan Fold Belt are very prospective for the discovery of a major porphyry copper gold deposit. Follow up field work has commenced this week on the four priority prospects with further more detailed field checking and rock chip sampling planned. The results of this work will be used to help prioritise targets for ground geophysics and drilling as soon as practicable.
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