Please use this identifier to cite or link to this item: https://geoscience.nt.gov.au/gemis/ntgsjspui/handle/1/86382
Export to Endnote
Title: Annual report for MLN's 196 - 200 incl. Mount Wells Northern Territory expiration date 20 March 2007 (currently under application for renewal)
Title Holder / Company: Softwood Plantations
Report id: CR2008-0244
Tenure: MLN196;  MLN197;  MLN198;  MLN199;  MLN200
Year: 2008
Author: Morrison, J
Abstract: The Mineral leases are located on Mount Wells. Mt Wells is located approximately 200 km?s south east from Darwin, in the Pine Creek Region. (Latitude 13o30?03? S and Longitude 131o43? 10? E) The first grant date for the tenement was on the 21st of March 1970 and expired on the 20th of March 2007. Currently the mining leases are under application for renewal. ?Softwood? also purchased the adjacent land surrounding these tenements as well as the disused processing plant and infrastructure at the site. Softwood Plantations was subsequently bought by ?Outback Metals Pty Ltd? in 2007. The Mt. Wells area located within the central portion of the Pine Creek Geosyncline, a Palaeoproterozoic structure containing fluvial and basal sediments. Mt Wells is dominated by structurally complex siltstones, sandy siltstones, phyllites, slates, and greywacke and pebble conglomerates of the Burrell Creek Formation (Finniss River Group). Rare carbonates and fine-grained felsic igneous rocks are also present. In the north east portion the Mount Bonnie Formation outcrops and is mainly composed of interbedded carbonaceous sericitic, pyritic or chloritic. slate, phyllite, mudstone and siltstone; fine to coarse felspathic metagreywacke; ferruginous phyllite (metasiltstone) with chert bands, lenses and nodules also occur in this formation, which is prospective for Vein Au, Polymetallic Cu, Pb, Zn, Ag veins. Mt. Wells is located on a substantially elevated hill containing en-echelon lodes of copper & tin ore. At Mt. Wells there are six tin-quartz lodes namely; 1. East Lode, 2. No 1 Copper Lode, 3. No 2 Copper lode, 4. Main Lode, 5. West Lode, 6. Northwest Lode. These lodes are essentially tension ? fill quartz veins, striking 015 - 025, dipping 75- 85 east and have a strike length of up to 1km. The host rocks are siltstone and greywacke of the Burrell Creek Formation which form a north trending anticline. The width of the individual lodes averages 2 metres (0.5m ? 5m) arranged in an enechelon pattern. Contacts with the host rock are sharp and there is no evidence of displacement or movement. Lode occurring near the contact is brecciated. Branching of lodes into 3 or 4 narrow veins is common. Cassiterite (SnO2) occurs as single coarse crystals or as aggregates along the hanging wall of most lodes. The coarseness of the tin mineralisation within the quartz lode combined with its erratic distribution, contribute to the inherent spotty nature of the mineralisation producing a high-nugget effect inducing contrast between adjacent lode sample assay results of near zero to several percent tin respectively. The centre of the lodes is generally barren while the footwall is marked by hematite (oxidised sulphides) ? quartz breccia which also contains cassiterite. The above breccia zone also occurs on the hanging wall in No 2 and No 3 levels possibly representing late stage sulphide-rich mineralisation. Sulphides are more common to the north side of the lode. In primary ore, pyrite, chalcopyrite, arsenopyrite and pyrrhotite are common. Rare wolframite and molybdenite are also present. Common gangue minerals are quartz, muscovite, tourmaline, feldspar and chlorite. Within the oxidised zone, extending to a depth of at least 50 metres the ?lode? comprises quartz, hematite, limonite, cassiterite, malachite, chalcocite, bornite, covellite and scorodite. Diamond drill cores have intersected lodes to a depth of 200 metres also intersecting a cupola of greisenised biotite / muscovite granite at depths of 150 ? 200 metres. Most ?lode? does not continue into the granite however minor quartz-cassiterite veins are present within the granite and one such vein has been correlated with the Main Lode. Geochemistry by Mookhey (1971) indicates an increase in tin and Cu values going away from the granite. The greisenised granite (intersected in drill holes) is equigranular; medium grained and contains muscovite, microcline, perthite, quartz and traces of biotite. Accessory minerals include fluorite, sphene, apatite, rutile, hornblende, pyrite, pyrrhotite, arsenopyrite, cassiterite and chalcopyrite. West Lode and Main/Intermediate lodes located at Mt Wells. Previous drill programs at this site focussed on the potential of deeper ore which would be accessed by underground methods. ?Softwood? carried out a drilling and sampling program to target shallower ore. Several areas of high grade tin ore were discovered during the surface sampling. Following assays of the drill and rock chip sampling, a plan was developed for the surface of the Mt Wells tenements and all data compiled from ?Territory? and ?Softwood? and then plotted using computer modelling techniques. At this time period the price of tin fell from $2.4426 USD / Lb to $1.6783 USD/Lb. It was deemed uneconomical to continue to explore and mine at this time. The increase in tin prices over the last year has warranted the renewal of detailed feasibility studies to commence. As part of the desktop studies completed by Softwood Plantations a review was made of the resources estimates in 2000. This review was relevant to determine the accuracy of previous estimates as the accuracy of information will affect the mining widths, which will be a factor of the current metal prices and mining processes. There were sufficient assays of vein material to say that in the main lode systems (West, Main and East), the average quartz grade is 1.5-2% Sn, and in the tourmaline/quartz greisens 1%. The metal prices will affect the actual mining process as the as the ore grade zones 1 and 2 are separated by below cut off grade material that will cause dilution. High metal prices will mean a bigger bucket on the excavator with less detail taking out the quartz vein, and the inclusion of more of the lower grade tourmaline breccias. This will naturally mean more tonnes of ore and will affect the ore to waste ratio. Since the transaction by ?Outback Metals? was proposed in May 2007, an audit of the current resource statements has been made as well as the development of the Company ?Outback Metals Limited.? The MLN?S 196, 197, 198, 199, and 200 have been visited on a number of occasions over the previous term. Site visits were made to identify assets as outlined in the transaction between Softwood and Outback, as well as to familiarize the team with the site and begin planning an exploration program. The majority of expenditure in time and expenses during 2007-2008 period was to develop a drilling program and to begin implementing the set up of the project. A desktop study of the previous work on the area was carried out when Outback acquired the Mt Wells rights. This study identified the previous exploration, as well as the strike and orientation of the mineralisation. This information was used to develop a 3D model of the site. Preliminary set up issues were addressed such as access to the site from the Freehold land owner and getting drilling and fuel contracts drawn up. Other concerns that were addressed related to the up keep of the site such as firebreaks and general issues related to maintaining the site. A site visit was made and sediment samples taken to identify areas of focus on the Mount Wells Site. These sediments were then used to test a hand held XRF analyser that the Company is considering purchasing to assist with the exploration on the Mt Wells surrounding areas. The drill program was developed using the 3D model of the site and the known mineralisation. The objective of the initial drill program is to substantiate historical drilling on the site and establish a JORC compliant resource statement. A Mine Management Plan was submitted to the NTGS on Friday the 16th of May and once the plan is approved b the NTGS a drilling programme will begin on the mineral leases in question. The initial drilling accesses and sites are being used to twin previous holes. The aim of this is to substantiate the integrity of previous drilling. This will be followed by a infill drilling program to identify the extent of the mineralisation and identify any areas of Mt Wells that have not previously been explored. Outback Metals Limited requests that title to this Mining leases be retained by its subsidiary Softwood Plantations Pty Ltd. The titles are essential to the exploration programme proposed by ?Outback? and the company looks forward to proceeding with the exploration and development of the mineral leases and the surrounding area which is wholly owned by Softwood Plantations.
Date Added: 3-Oct-2017
Appears in Collections:Minerals Exploration Reports (MEX)

Files in this Report:
File SizeFormat Add to
Download
CR20080244_2008_GA.pdf389.74 kBPDF Add


Items in GEMIS are protected by copyright unless otherwise indicated.

Get Adobe Reader