17 November 2014
AIM: AAU
CONFIRMATION OF PORPHYRY BY GEOPHYSICS: KIZILITEPE SECTOR
Ariana Resources plc ("Ariana" or "the Company"), the gold exploration and development company focused on Turkey, is pleased to announce the confirmation of a mineralised sub-volcanic porphyry at the Kepez prospect in the Kiziltepe Sector of the Red Rabbit Project ("Red Rabbit"), which it holds in a joint venture with Proccea Construction Co.
Highlights:
Dr. Kerim Sener, Managing Director, commented:
"The confirmation of a significant volcanic complex containing a mineralised sub-volcanic porphyry at Kepez is a major step-forward for the Company. This discovery considerably enhances the prospectivity of the entire project area and underpins the potential for significant gold mineralisation to be indentified in the proximity of this porphyry centre. Evidence for this comes from the recent soil survey results, which highlight the coincidence of geochemical anomalism with high-temperature alteration in the periphery of the intrusion. Numerous rock-chips collected from various quartz veins developed within or outside of this intrusion are demonstrated to contain significant gold and silver grades in places.
The Kepez Porphyry, located just 6km from the planned Kiziltepe Mine, will become an important focus for future drilling programmes on the project, as we look to expand our resource base across the region. Areas such as Kepez North, occurring in the immediate periphery of the porphyry, have already demonstrated the potential for high-grade resources and we are confident that other examples of this style of mineralisation occur throughout the project area."
Kepez Porphyry Description
The Kepez porphyry was identified in geological mapping as a 1,600m x 900m quartz-feldspar porphyry of rhyolitic composition. The recent ground magnetic geophysical survey suggests an intrusive character to the porphyry and identifies it as a sub-volcanic stock located on a 5km diameter ring-structure occurring within a volcanic caldera. The porphyry occurs at the point where the ring-structure is cross-cut by a major NNW-trending dextral strike-slip fault system (Figure 1). Based on the geophysical data, the porphyry body appears to have greater dimensions at depth than its surface outcrop suggests, extending 2,000m x 1,800m.
A generally weakly gold mineralised (up to 0.1 to 0.5 g/t Au) 1,100m x 180m zone of silica-pyrite alteration cuts across the outcropping porphyry. At its northern end lies a zone of significant silver mineralisation in late-stage epithermal veins with an average grade based on composite rock-chip sampling of 64 g/t Ag and a peak grade of 383 g/t Ag (from 42 samples). Other high-grade gold and silver bearing veins occur in the immediate periphery of this intrusive complex, notably at Kepez South and at Kepez North. Late-stage epithermal veins at Kepez North carry an average grade based on composite rock-chip sampling of 4.7 g/t Au with a peak grade of 41.8 g/t Au (from 184 samples). Kepez North already contains an Indicated JORC resource of approximately 9,000 oz gold equivalent, and this style of exceptionally high-grade mineralisation is a target for future exploration in the vicinity of the porphyry.
A detailed soil X-ray fluorescence ("XRF") survey highlights an arsenic and antimony anomaly centred on the porphyry intrusion in addition to enhanced potassium and rubidium/strontium levels coupled with a manganese and calcium depletion zone, which is indicative of both the hypogene and supergene alteration and mineralisation processes involved in this area (Figure 2). It is important to note that the arsenic levels encountered are at trace concentrations though these remain above background levels. To the immediate south of the porphyry, part of the alteration zone shows significant molybdenum enrichment, coinciding with an area of gold-bearing vein-type mineralisation at Kepez South (Figure 3). Molybdenum (up to 911ppm), antimony (up to 3,960ppm) and barium (up to 2,680ppm) occurs in rock-chips both within the alteration zone but also in veins within the intrusion and in certain silicified ledges identified in the vicinity.
A large part of the mapped intrusion displays high-temperature advanced argillic alteration of the rhyolitic rocks, including extensive silicification. Over significant areas, kaolinite-alunite-dickite (±nacrite) alteration is observed, with strong sericitic alteration occurring generally on the margins. Kaolinite crystallinity is enhanced within the most altered parts of the system and corresponds broadly to the occurrence of higher gold and silver grades in some vein material. Illite/smectite alteration is also seen in places, particularly toward the outer edges of the alteration zone. These alteration features are characteristic of high-sulphidation epithermal systems, and in this area it appears that such a system developed in the vicinity of the Kepez porphyry which was then overprinted by several generations of low-sulphidation veins, some of which carry high gold grades (1 to 5 g/t Au or more).
The presence of an active hot-spring in this area, located approximately 2.5km to the south of the centre of the Kepez intrusion, demonstrates a continuation of hydrothermal activity from the Miocene epoch (mineralisation at Kiziltepe has been dated to approx. 18 million years ago) up to the present. Proximal and long-lived hot springs are characteristic features of many large epithermal gold projects in Turkey and around the world. Also the association between mineralised porphyry systems and both high- and low-sulphidation mineral systems is demonstrated at a number of deposits world-wide, such as those at Lepanto in the Philippines.
Following the completion of the geophysics programme, the caldera model for the genesis of the gold-silver mineralisation across the Kiziltepe Sector (announced 28 November 2013) remains the most relevant and useful working hypothesis. The geophysical data has largely supported the model and has highlighted the presence of several structures that are likely to have been significant in the evolution of the epithermal mineral system across the area.
Figure 1: Total Magnetic Intensity (TMI) geophysical map of the Kiziltepe Sector (TMI has been reduced to pole). Superimposed on this map are major structural features as interpreted from geophysical data in addition to field mapping and satellite data interpretation. The Kepez porphyry intrusion is shown towards the bottom right of the map, along with associated alteration and mineralisation zones identified from remote-sensing, field mapping and geochemical analysis. Apart from the mapped intrusions and ophiolite, all areas encompassed by the map are covered by Miocene volcanic rocks of dacitic to rhyolitic composition. Highest grade rock-chips are also identified at certain locations.
Figure 2: Soil XRF geochemical map of the Kiziltepe Sector, showing arsenic concentration in ppm. Superimposed on this map are major structural features as interpreted from geophysical data in addition to field mapping. The Kepez porphyry intrusion is shown towards the bottom right of the map, along with associated alteration and mineralisation zones identified from remote-sensing, field mapping and geochemical analysis. Apart from the mapped intrusions and ophiolite, all areas encompassed by the map are covered by Miocene volcanic rocks of dacitic to rhyolitic composition. Highest grade rock-chips are also identified at certain locations.
Figure 3: Alteration map of the Kepez porphyry area based on satellite data analysis (rainbow coloured pixels) coupled with field mapping and geochemical data. To the south of the mapped porphyry lies a broad zone of molybdenum enrichment, which coincides with a cluster of gold bearing veins which sit within a zone of potassium enrichment and manganese and calcium depletion associated with alteration.
Contacts:
Ariana Resources plc | Tel: +44 (0) 20 7407 3616 |
Michael de Villiers, Chairman | |
Kerim Sener, Managing Director | |
Beaumont Cornish Limited | Tel: +44 (0) 20 7628 3396 |
Roland Cornish / Felicity Geidt | |
Beaufort Securities Limited | Tel: +44 (0) 20 7382 8300 |
Saif Janjua | |
Loeb Aron & Company Ltd. | Tel: +44 (0) 20 7628 1128 |
John Beresford-Peirse / Dr. Frank Lucas | |
St Brides Media & Finance Ltd | Tel: +44 (0) 20 7236 1177 |
Susie Geliher / Lottie Brocklehurst | |
Editors' note:
Dr Kerim Sener, BSc (Hons), MSc, PhD, is the Managing Director of Ariana Resources plc. A graduate of the University of Southampton in Geology, he also holds a Master's degree from the Royal School of Mines (Imperial College, London) in Mineral Exploration and a doctorate from the University of Western Australia. He is a Fellow of The Geological Society of London and has worked in geological research and mineral consultancy in Southern Africa and Australia. He has read and approved the technical disclosure in this regulatory announcement.
About Ariana Resources:
Ariana is an exploration and development company focused on epithermal gold-silver and porphyry copper-gold deposits in Turkey. The Company is developing a portfolio of prospective licences selected on the basis of its in-house geological and remote-sensing database, on its own in western Turkey and in Joint Venture with Eldorado Gold Corporation in north-eastern Turkey. Eldorado owns 51% of this joint venture and are fully funding all exploration work on the JV properties, while Ariana owns 49%. The total resource inventory within this JV is 1.09 million ounces of gold.
The Company's flagship assets are its Kiziltepe and Tavsan gold projects which form the Red Rabbit Gold Project. Both contain a series of prospects, within two prolific mineralised districts in the Western Anatolian Volcanic and Extensional (WAVE) Province in western Turkey. This Province hosts the largest operating gold mines in Turkey and remains highly prospective for new porphyry and epithermal deposits. These core projects, which are separated by a distance of 75km, are presently being assessed as to their economic merits and now form part of a Joint Venture with Proccea Construction Co. The total resource inventory at the Red Rabbit Project stands at 475,000 ounces of gold equivalent.
Beaufort Securities Limited and Loeb Aron & Company Ltd. are joint brokers to the Company and Beaumont Cornish Limited is the Company's Nominated Adviser.
For further information on Ariana you are invited to visit the Company's website at www.arianaresources.com.
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