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Sayabouly Project

Figure 1: Sayabouly Project Prospects and geology

Phu Lon Nickel Prospect

Santana’s exploration focus at Sayabouly is the Phu Lon Nickel Prospect. This prospect has previously recorded significant surface nickel-platinum-chromium-cobalt results, over a 14 x 1km area within an ultramafic intrusive. Mineralisation is interpreted to be of magmatic sulphide style (not lateritic), with results taken from trenches of the weathered ultramafic and below the lateritic profile recording 975m @ 0.51% Ni (including 42m @ 1.02% Ni) and 67m @ 0.83 % Ni (Santana ASX Announcement 17 July 2019). No drilling has been completed at this location and a maiden drilling program will commence mid-January 2020.

Nakhan Gold Prospect

The Nakhan Prospect is a gold mineralised target that has previously recorded significant results from trenching and shallow drilling including 4m @ 16.95g/t and 9m @ 5.29g/t from 14m respectively (Santana ASX Announcement 17 July 2019). Mineralisation is open along strike and at depth, and while the company’s exploration priority is the Phu Lon Nickel Prospect, further work is warranted at this location.

Phu Lon Copper

The Phu Lon Copper Prospect is located immediately west of the Phu Lon Nickel Prospect. This target is described as a broad zone of anomalous copper mineralisation covering an area of 16.5km x 3km. The anomalism is within an andesitic volcanic rock unit, with geological mapping at this location identifying native copper and malachite and chalcopyrite copper minerals.


Property Description and Location

The Sayabouly Project is located in the Sayabouly Province, approximately 250km north-west of the capital Vientiane (Figure 2), accessed by a sealed highway. The concession covers an area of 488km2, with Santana holding an effective 85% interest in the project.

Figure 2: Location of Santana’s Sayabouly Project in Laos.


Geology

Regional Geological Setting

The Sayabouly Project is located within the Carboniferous-Permian Loei-Phetchabun Fold Belt (Figure 3), a belt of calc-alkaline volcanic rocks that extends north–south along the western margin of the Khorat Plateau from Lao in the north to Ko Chang in the Gulf of Thailand in the south.

Figure 3: Tectonic map showing continental blocks of mainland SE Asia and region

In Lao, the belt is characterized by andesitic volcanic rocks and granitic subvolcanic intrusions. The volcanic units were extruded onto a prograding sequence of shallow shelf sediments. Gold mineralisation in both Lao and Thailand is genetically related to this volcano- plutonic event, including the Chatree gold deposit in Thailand.

The regional scale Naxang Fault traverses the area from SW to NE. In the SW it forms the faulted contact between the andesitic volcanic sediment and shallow marine sedimentary rocks, which offset the Phu Lon Nickel Prospect mafic- ultramafic intrusion.

Local Geology

The eastern half of the Sayabouly Project is dominated by mudstones with minor interbedded shale and siltstones (Figure 4). The western half is dominated by andesitic volcanic units that interfinger with volcano-lithic sedimentary rocks. This volcanic-sedimentary sequence is intruded by sub-volcanic intrusions.

There are three main prospects within the project: Phu Lon Nickel, Nakhan Gold and Phu Lon Copper, shown in Figure 3.

Figure 4: Local geology and main prospects within the Sayabouly Project.

Phu Lon Nickel

Phu Lon Ni Prospect is a north-trending 1.0km x 14km polymetallic geochemical anomaly that is partially overlapped by the Phu Lon Copper Prospect. Pervasive nickel-platinum-cobalt-chromium mineralisation, demonstrated through soil sampling and trenching, is hosted within a mafic- ultramafic dyke that consists of a basal unit of dunite, an outer layer of pyroxenite and outermost layer of gabbro. The dyke intrudes close to the contact of the western andesitic volcano-sedimentary sequence and the eastern pelitic sedimentary sequence.

Significant results were previously recorded from the trench sampling, including 975m @ 0.51% Ni (including 42m @ 1.02% Ni) shown in Figure 5. These samples were taken from the weathered ultramafic rocks and below the lateritic profile. The style of mineralisation is interpreted to be magmatic sulphide which is supported by petrological analysis of mineralised ultramafic rock-chip samples. This analysis identified the sulphide minerals pentlandite (nickel sulphide), cobalt-pentlandite (cobalt-nickel sulphide) and chalcopyrite (copper sulphide) (Santana ASX Announcement 25 November 2019).

Figure 5: Phu Lon Nickel significant trench results (Santana ASX Announcement 17 July 2019)

An induced polarisation survey was completed at the Phu Lon Nickel Prospect previously and identified anomalies coincident with the surface nickel mineralisation. This survey is an electrical geophysical method that can define sulphide mineralisation at depth. The survey defined zones of chargeability highs with a corresponding resistivity lows, and is interpreted to be a zone of nickel sulphide mineralisation at depth (Figure 6), supporting a magmatic style of mineralisation at the prospect.

Figure 6: Induced Polarisation Chargeability section with planned drilling, northern location of the Phu Lon Prospect (Santana ASX Announcement 17 July 2019).

No drilling of the Phu Lon Nickel Prospect has been completed to date, with the trench results and corresponding geophysical anomalies at depth represent compelling targets. A maiden drilling program testing the prospect will commence mid-January 2020.

Nakhan Gold Prospect

The Nakhan Prospect is a zone of gold anomalism defined by stream, soil, and shallow rotary air blast (RAB) drilling, covering an area of 2,000m x 800m. Mineralisation is interpreted to be intrusive related, with mineralisation located within quartz veins and hosted by a granodiorite. The prospect is covered by shallow sediments and obscures the mineralisation. Significant trench and RAB results have previously been recorded (Figure 7), which is open along strike and at depth. While the Phu Lon Nickel Prospect is Santana’s exploration focus, the results from Nakhan warrant further investigation.

Figure 7: Nakhan Prospect with gradient array induced polarisation overlaid by RAB drilling and trench results (Santana ASX Announcement 17 July 2019)

Phu Lon Copper

The Phu Lon Copper Prospect is located immediately west of the Phu Lon Nickel Prospect. This target is described as a broad zone of anomalous copper mineralisation covering an area of 16.5km x 3km. The anomalism is within an andesitic volcanic rock unit, with geological mapping at this location identifying native copper and malachite and chalcopyrite copper minerals.

Figure 8: Phu Lon Copper Prospect with anomalous soil sample results