3DIP survey outlines a large, virtually untested, buried target over 1,000m of strike at Greatland’s Saddle Reefs prospect coincident with high-grade gold mineralisation at surface
Greatland Gold plc (AIM: GGP), the precious and base metals exploration and development company, is pleased to announce that results of a 3D Induced Polarisation (“3DIP”) survey have identified a large, buried geophysical target at the Saddle Reefs prospect, located in the Company’s 100% owned Black Hills licence in the Paterson region of Western Australia. The body lies subparallel to the strike of gold mineralisation identified at surface.
Highlights of 3DIP results
· High quality IP data was collected and used to generate 3D inversion models;
· Results have outlined a large, coherent conductive body over 1,000m of strike, spatially coincident with gold mineralisation identified at surface;
· The conductive body has dimensions of approximately 1,000m long, 200m wide and 150m thick, and is open to the south-east;
· Depth to top of the body ranges from 150m to 200m below surface, a depth which is virtually untested by historic drilling in the Saddle Reefs area.
3DIP models have been reviewed in conjunction with surface geochemical and geological information at Saddle Reefs, and drill targets have been selected to test the orientation and tenor of gold mineralisation.
Gervaise Heddle, Chief Executive Officer, commented: “We are very excited by the excellent results from the 3DIP survey at Black Hills which has outlined a large, new and virtually untested gold target at the Saddle Reefs prospect. Saddle Reefs has the potential to host gold mineralisation from surface to significant depths, and these results reinforce our view that it represents a high priority exploration target for us.
“The prospectivity of the Paterson region has attracted the attention of major industry players and we look forward to a busy exploration season in the Paterson region next year which will include Greatland’s first drilling campaign at Black Hills.”
In June 2018, Greatland commenced it first exploration campaign at Black Hills. Multiple gold nuggets were found in thin sand cover within the first few days of the campaign, establishing the presence of high grade gold mineralisation at surface at the Saddle Reefs prospect (see announcements dated 21 June 2018 and 2 July 2018). Results from additional rock chip sampling over the prospect returned many values over 10g/t gold, peaking at 81.7g/t gold, and these results approximately quadrupled the strike length of surface gold mineralisation from 200m to 800m (see announcement dated 4 September 2018).
In July/August 2018, a comprehensive Induced Polarisation survey was conducted covering a strike length of 1,600 metres over the zone of surface gold mineralisation at the Saddle Reefs prospect and immediate strike extensions (see announcement dated 17 July 2018). 3D inversion models were generated from the IP data and results of those models are reported in this announcement.
Overview of Paterson Project and Black Hills licence
The Company’s Paterson project comprises the Havieron, Paterson Range East, and Black Hills licences, located in the Paterson region of northern Western Australia. The three licences collectively cover more than 385 square kilometres prospective for iron-oxide-copper-gold (“IOCG”) deposits and Telfer style gold deposits.
The Paterson region hosts several large gold and copper deposits such as Telfer and Nifty. The region has been subject to more recent exploration which has outlined several other deposits including Magnum (Au), Calibre (Au), O’Callaghans (W, Cu) and Maroochydore (Cu). The region is remote, however infrastructure is good with several operating mines, roads, formed tracks and rail networks nearby which branch out from the regional industrial hub of Port Hedland 500km to the west.
The Black Hills licence, E45/4512, lies 30 km east of the large Telfer gold mine. Black Hills is a granted exploration licence that covers 25 square kilometres and sits adjacent to the Company’s Havieron exploration licence. The Black Hills licence is regarded as having high potential to host gold deposits similar to Telfer. There has been a reasonable amount of historical exploration work at Black Hills with several discrete zones of mineralisation identified over 5km of strike. Historical rock chip samples have returned up to 90g/t gold, and commonly 20g/t gold, with free (visible) gold in places. Historic drill intercepts include 3m at 9.14g/t gold from 26m downhole (incl. 1m at 21.2g/t from 27m (CBR073)), 1m at 10.0g/t gold from 16m (CBH138), 1m at 4.93g/t from 12m (CBH071) and 1m at 3.12g/t from 37m (NBH004). Historical RC drill spacing appears quite broad with holes at least 400m apart, some up to 600m.
Gold prospects identified to date extend from Black Hills into the north western parts of the Havieron licence. Proterozoic sandstone and carbonate rocks of the Yeneena Group formations are present, including the Telfer Formation, in a domal structure which is the equivalent geology to that of the large Telfer gold deposit located 30km to the west.
A large amount of historical surface exploration data for the Black Hills area has been compiled and merged into the Company’s database. Gold mineralisation has been outlined at several prospects throughout the licence including Saddle Reefs, Eastern, Rogers and Northern Granites (within an area of 6.5km x 2km).
Strong surface gold mineralisation is present at the Saddle Reefs prospect with historical rock chips including 55.6g/t, 20.0g/t, 19.65g/t, 18.45g/t and 17.0g/t over an area of approximately 1,400m x 800m. The zone has a north-westly trend and sporadic drilling with results including 3m at 9.14g/t gold from 26m downhole, including 1m at 21.2g/t from 27m, in hole CBR073. This zone is in the core of an anticlinal feature and, overall, is gold prospective over a strike length of approximately 3km.
At the Eastern prospect a linear zone of gold mineralised stratigraphy is apparent over a strike of approximately 4km. Historical surface rock chip results include 1.9g/t gold, 1.2g/t gold and 1.0g/t gold. Broad spaced drilling along the zone has returned results including 1m at 10.0g/t gold from 16m (CBH138), 1m a 4.93g/t from 12m (CBH071) and 1m at 3.12g/t from 37m (NBH004). The mineralisation appears to track along a structural contact and the focus will be on identifying the higher grade mineralisation along this trend.
The other prospects of Rogers and Northern Granites show prospective gold mineralisation at surface with historical rock chip results including 50.2g/t and 10.45g/t at Rogers and 6.9g/t at Northern Granites. Drill testing is limited but results have included 1m at 1.48g/t from 38m (NBH008) at Rogers and 1m at 2.35g/t gold from 5m (CBH253) at Northern Granites.
The Company commenced field work at Black Hills in June 2018 (see announcement dated 18 June 2018). Work focused on the Saddle Reefs and Rogers areas collecting rock chip samples and locating historical access. The host sequence of Proterozoic sandstones and limestones outcrop through relatively thin sand cover. Numerous indications of mineralisation in bedrock are apparent. Gossanous samples were collected from outcrop, visible gold recovered from rock chip samples, and gold nuggets were found in thin sand cover at Saddle Reefs (as announced 21 June and 2 July 2018).
At Saddle Reefs, the mineralised sequence outcrops through a thin veneer of sand and gravel. Rock chip samples were collected over a strike length of approximately 800m with results over 10g/t including 81.7g/t, 45.7g/t, 37.6g/t, 33.9g/t, 28.2g/t and 23.5g/t. Many also showed high silver above 10g/t up to a maximum of 106.1g/t. Gold (and silver) mineralisation in bedrock has been identified over a strike length of approximately 800m at Saddle Reefs.
A comprehensive IP program over Saddle Reefs was designed and implemented in conjunction with external consultants, and undertaken during Q3 2018 (as announced 17 July 2018). Total strike length covered was 1,600m. Transmitter and receiver lines were 100m apart and station spacing along lines was 20-40m. Thorough independent QA/QC of collected IP information was carried out and it was concluded the data is of high quality.
Modern 3D inversion models of resultant IP data were generated. These models have outlined a large, coherent conductive body over 1,000m of strike spatially co-incident with gold mineralisation identified at surface. The body lies subparallel to the strike of gold mineralisation identified at surface and has dimensions of approximately 1,000m long, 200m wide and 150m thick. The body plunges gently south-east mirroring the overall structural plunge of the outcropping geology and is open to the south-east. Depth to top of the body ranges from 150m to 200m below surface. The majority of historical drill holes at the Saddle Reef prospect were to maximum depths of only 50m.
Detailed 3DIP subsurface models have been reviewed in conjunction with surface geochemical and geological information at Saddle Reefs. Drill targets have been selected to test the orientation and tenor of gold mineralisation.
The Company has received all required approvals from the Western Australian Department of Mines, Industry Regulation and Safety (‘DMIRS’) for a drilling programme at Black Hills (as announced 4 September 2018).
Additional information on the Black Hills licence can be found under ‘Paterson’ on the Company web site at www.greatlandgold.com/projects.
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