AMSTERDAM, The Netherlands , May 30, 2017 /CNW/ - Meridian Mining S.E. (TSX V: MNO) ("Meridian" or the "Company"), today provided an update on exploration results from its Bom Futuro tin joint venture in the state of Rondônia, in northwestern Brazil .
HIGHLIGHTS
- Ground orientation surveys identify target for concealed intrusive body underpinning the mineralized veins and pegmatites of the Bom Futuro Hill.
- Near-mine ground penetrating radar surveys confirm signature of undeveloped palaeochannels.
- First phase regional surveys identified new palaeochannel targets over the broader licence area.
"The Bom Futuro Joint Venture presents an outstanding opportunity to apply cutting edge geophysical exploration techniques to a very significant mineral centre," said Anthony Julien , President and CEO of Meridian. "The historical production of 192,000t of tin ranks Bom Futuro as Brazil's second largest tin mine, and the area is yet to receive the full benefits of modern exploration. The results of these initial surveys show great promise for generating new targets to realize the full potential of the broader project area."
MERIDIAN GEOPHYSICAL PROGRAM
Meridian concluded a first phase of ground geophysics in March, trialing various methods to assist in the definition of primary bedrock and palaeochannel targets.
The Brazilian geophysical consultancy AFC Geofisica conducted ground-based gravity, magnetic, and chargeability / resistivity surveys. These surveys covered the northern half of the Bom Futuro Hill and extended northwards, covering an area of ~2km2 (Figure 1). The data has undergone processing by AFC and Company's independent geophysical consultancy Core Geophysics. Core Geophysics also supervised an 80 line kilometre trial Ground Penetrating Radar (GPR) survey, using cutting-edge UltraGPR technology developed by Groundradar Inc. The GPR surveys were particularly designed to test palaeochannel targets.
Significant outcomes of the drilling and mapping program include:
- A target for a concealed intrusion underpinning the Bom Futuro vein and pegmatite ring structures has been identified in the AFC survey block. Gradient Array IP surveys identified areas of enhanced chargeability which exhibited a similar trend to the ring structure pattern. These may be related to accessory base metal sulphides that have been recorded separately to the cassiterite mineralization. More particularly, inversions of the magnetic data identified a deeper seated anomaly underlying the north-east quadrant of the Bom Futuro ring structure system (Figure 2). These ring structures sit in gneissic host rocks in a "roof pendant" setting, above an untested source intrusion at depth. The inversion model presents the first imaging of targets at depth beneath the hill. Additional surveys will be undertaken to complete full coverage of the hill to test for satellite bodies and rank deep-seated drill targets.
- Ground penetrating radar orientation surveys have proved very effective at delineating the palaeochannel signature in controlled settings close to the Bom Futuro mining operations. The palaeochannels are known to be several hundred meters wide and are filled by unconsolidated sands, gravels and clays. The tin mineral cassiterite can be dispersed through the channel sequence, but is particularly concentrated in the rich channel gravels at the base of the sequence. Orientation surveys targeted the projection of a palaeochannel position, eastwards from a location where mining operations terminated adjacent to an access road (Figure 1, Figure 3). Resistivity surveys were first undertaken by AFC, indicating that the uppermost soil / colluvium is generally resistive, the palaeochannel positions themselves are more conductive, and the bedrock sequence is resistive. GPR lines provided a good resolution of the channel structure (Figure 4), showing stratification in the channel sequence, and identifying basal irregularities.
- GPR trials have been extended more regionally through the "Non-Explored Area", with ~80 line kilometers completed in broadly spaced north-south and east-west survey pattern. These surveys have identified analogous channel patterns, presenting a range of initial targets for placer mineralization (Figure 5). The Company will be conducting additional surveys to confirm the concealed palaeo-drainage pattern. Options include aerial surveys targeting the full licence area, mapping the conductivity response of the channel pattern (in addition to resolving potential bedrock targets), and infill ground based surveys for high resolution definition of the channel structure.
View original content with multimedia: http://www.newswire.ca/en/releases/archive/May2017/30/c6315.html