The Panorama project consists of three adjoining exploration licences, covering 155 square kilometres, located in the Pilbara region of Western Australia, in an area that Greatland considers to be highly prospective for gold and cobalt.
The Pilbara region is currently experiencing a surge in gold exploration activity. Greatland has recently identified potential gold targets on both the north-western and southern licence (see announcement dated 24 October 2017).
Geology of the area is predominantly greenstone and granite of the Archean Pilbara Craton in northern Western Australia, and younger overlying sedimentary and volcanic sequences.
Drainage samples were collected during the mid 1990s and during 2015. Initial results of this review have identified approximately twenty gold in stream anomalies within the Company’s 130 square kilometre project area. Gold anomalism in streams peaks at 68.5ppb and 60ppb. Historic gold mines and alluvial occurrences are apparent immediately north of the Company’s licences with the mineralised trend and geological strike continuing south into Greatland licences.
Detailed review of historic work revealed many rock chip samples with an elevated gold response from within the project area. Rock chip samples were collected during the mid to late 1990s, mainly over the northern parts of the project area. The most significant samples identified to date lie along a north-south trending zone approximately 3.2km long with rock chip results including 1.4g/t, 2.5g/t, 2.8g/t, 3.2g/t, 10.5g/t, 14.0g/t, 14.5g/t, 20.0g/t and 66.0g/t gold. The geological setting is a prominent ridge marking the structural contact of basaltic and ultramafic rocks of Archean age. Field reconnaissance along this zone has been completed and visual indications of mineralisation are present.
Greatland carried out sporadic rock chip sampling along the Northern zone during 2017 with results including 18.45g/t, 1.82g/t, 0.71g/t, and 0.61g/t gold over approximately 3.2km of strike, confirming the presence of gold mineralisation.
During June 2019 Greatland commenced field operations with reconnaissance activities and surface geochemical work primarily focussed on Archean lode style gold mineralisation. Numerous gold nuggets were found in thin soil cover over several hundred metres of strike along the mineralised zone. Gold nuggets were found further south along strike from mineralisation previously identified, extending the strike extent of the mineralised trend from 3.2km to 6.1km.
Ongoing work during July and August 2019 has included phase one geochemical sampling at a density of 100m x 50m and 200m x 50m resulting in the collection of 468 samples.
A detailed, low level airborne magnetic survey covering the entire project area was commissioned by the Company. The survey comprised 8,092 line kilometres at a line spacing of 50m with a mean terrain clearance of 30m. The data is currently being processed and imaged and when integrated with the geochemical data sets, will assist Greatland with geological and structural interpretation of basement geology and provide better definition of existing targets.
Northern Zone Gold Nuggets
In the southern parts of the project area, detailed government geological mapping confirms the presence of lower Fortescue Group coarse grained sandstones and conglomerates at two locations adjacent to the Mt Roe Basalt. This is the equivalent geological setting to the target horizon of the Purdy’s Reward and Comet Well gold prospects currently under the operation of Novo Resources Corp. (TSV-V:NVO). The first area has a strike length of approximately 1.9km and the second 2.6km. One of the areas shows a co-incident gold in streams anomaly peaking at 4.6ppb gold.
Located approximately 200 kilometres south east of Port Hedland, the Panorama project occupies a dominant and strategic position across what is potentially the largest coherent cobalt in streams anomaly in Western Australia.
Stream sediment sampling data gathered by Anglo American Corporation in the early 1970s outlined a 25 kilometre long by 10 kilometre wide area of highly anomalous cobalt and up to 20 gold anomalies across the project area.
A systematic stream sediment sampling programme was completed over the broader Pilbara Region by Anglo American Corporation in the early 1970s. Samples were collected at a nominal 2km spacing and results from these samples have outlined a large cluster of high cobalt in streams. Stream sediments samples consistently returned over 50ppm cobalt, peaking at over 70ppm cobalt (against a background of less than 5ppm cobalt). The area covered by the anomalous cobalt is potentially the largest coherent cobalt in streams anomaly in Western Australia being more than 25 kilometres long and up to 10km wide covering an area of approximately 200 square kilometres. Greatland’s licences cover the bulk of the cobalt anomaly with five areas of anomalous cobalt identified in the southern parts of the Company’s licences. Cobalt anomalism in streams peaks at 70ppm and 65ppm.
Government geological mapping confirms the presence of coarse grained Archean sedimentary rocks striking over 18km from north to south throughout the Panorama project area.
Geology of the area is predominantly greenstone and granite of the Archean Pilbara Craton in northern Western Australia. The definitive source of the cobalt is not yet known, however it is likely to be localised in folding and faulting of the bedrock sequences; similar to other known styles of mineralisation in Archean greenstones elsewhere in the Pilbara displaying drill intercepts with high cobalt of up to 0.99%.
Historically the Pilbara Region is recognised for its gold and base metal mineralisation but apart from the work by Anglo American in the early 1970s very little subsequent exploration work has been carried out within the Panorama project area leaving the cobalt mineralisation untested. The large area of the cobalt in streams anomaly suggests a significant mineralising event has occurred.
The Mount Roe Basalt sits at the base of the Fortescue Group stratigraphy that is widespread throughout the Pilbara region of Western Australia. There is considerable geological discussion as to the origin of palaeo-placer gold in the Pilbara. It is known to occur in the Hardy Formation Conglomerate immediately overlying the Mount Roe basalt, and it is also known to occur in a stratigraphically lower conglomerate horizon occurring at the base of the Mt Roe Basalt. These palaeo-placer deposits are different to gold associated with other styles of mineralisation such as lode or epithermal types.