Posts Tagged base metal

Airborne EM – Deep base metal potential at Halls Peak in Australia

Posted by on Friday, 15 March, 2013

Precious Metal Resources has highlighted the deep base metal potential for large sedimentary exhalative system mineralisation at its Halls Peak project in New South Wales following airborne survey.

The tests point to similarities to world class base metal mines including Mt Isa, McArthur River and Cannington.

The conductive zones recorded at depths of around 400 metres by the recent VTEM helicopter survey extend beneath at least 14 square kilometres of the base metal field.

Past drilling and mining at Halls Peak has been too shallow to reach the potential high-grade lenses, instead intersecting either less mineralised beds within the overlying black shales, or high grade near surface mineralised fractures.

The copper-lead-zinc-silver mineralisation previously mined at Gibsons Mine, Faints Mine and bulk sampled by BHP at Khans Creek may represent such younger mineralisation.

Lower grade base metals lenses drilled and recently re-assayed by the company in the upper part of the Halls Peak SEDEX system are consistent with earlier and perhaps richer base metal lenses being present at depth.

SEDEX base metal deposits are formed when fluids carrying high concentrations of lead-zinc-silver-copper flow up large fractures (faults) in the earth and deposit their metals on the sides of these fractures and as fine crystals within the sea water.

These crystals then settle on the sea floor as metal rich beds (bedded sulphides).

Precious Metal’s exploration licences 4474 and 5339 are each subject to cooperation and investment agreements with Jiangsu Geology and Engineering to contribute $4 million toward exploration on both EL 4474 and EL 5339.

This is in addition to $2 million exploration funding which is well underway on the adjacent EL 7679, and under which the recent VTEM survey on this EL was carried out.

Source..


Geophysical Investigations on the Bathurst Mining Camp, New Brunswick

Posted by on Wednesday, 25 April, 2012

El Niño Ventures Inc. provides an update of the exploration work performed during the period July 1 to December 31, 2011 for its Bathurst Mining Camp (BMC) Base Metals Tri-Party agreement between El Nino, Votorantim Canada (VMC) and Xstrata Zinc Joint venture project in Bathurst, New Brunswick.

VMC’s work on the Xstrata-El Nino-Votorantim lands during this period included diamond drilling and ground EM surveys. A Time Domain EM survey was completed by Eastern Geophysics Ltd. on two third party optioned properties; and a combined borehole and surface TDEM survey was performed southeast of the BM&S No.6. The following table summarizes the work completed during the period July 1 to December 31, 2011.

Table-1 Exploration Activities Performed from July to December 31, 2011

Diamond Drilling:

As of December 31, 2011 a total of 16 holes, totaling 5,011 metres, have been completed on the Bathurst Mining Camp project (Figure 1). This Phase of exploration drilling campaign focused on geophysical and geochemical targets in the Brunswick Belt, two third party optioned properties in the Brunswick Belt and two optioned properties in the southwestern part of the BMC. The only hole drilled in the Camel Back project intersected widespread alteration with common traces of sphalerite.

Ground Geophysics- Large Loop Pulse EM:

A large grid was cut over the two third party optioned properties in Brunswick Belt and adjoining parts of Xstrata’s claims. Four loops were laid out and readings were measured in-loop and out-of-loop. Only a few weak areas of low resistivity were detected. Deep drilling, which subsequently tested the at depth extent of a narrow zone of subeconomic base metal mineralization, did not intersect any significant sulphide or base-metal mineralization.

Borehole Geophysics:

Borehole and surface Pulse EM surveys were performed southeast of Nepisiguit Dam in and around two drill holes completed in 2010 that intersected stockwork style copper-iron. Only a small off-hole response was found from the Pulse EM survey at Nepisiguit Dam and no further work is planned.

Figure1 –Drill Holes Location Map


Airborne Geophysics — Airborne Gravity Gradiometry (AGG):

Fugro Airborne Surveys completed the Phase 1 AGG survey over two large areas in the Bathurst Mining Camp in May 2011. This was the first ever commercial survey using the ‘Falcon’ Gravity Gradiometer in a helicopter platform. Figure 2 shows the outlines of the surveyed areas. A decision to proceed with Phase 2 and 3 will be contingent upon results obtained in Phase 1. Final results have now been received and are being interpreted in conjunction with Votorantim’s HeliTEM magnetic and EM data and other historical data, with the objective of identifying targets for drill testing in 2012.

Figure 2 –Airborne Gravity Gradiometry Survey


2012-2013 Exploration Plans

2012-Q1: Three drill holes were completed on third party options, in the Brunswick Belt, for a total of 1975 metres to test for base metal mineralization at depth. No significant mineralization was intersected. These three drill holes as well as three holes completed in Q4 2011 were tested by borehole pulse EM, however no anomalies were detected.

2012-Q2 to Q4 and 2013 Q1: It is planned to drill-test airborne gravity gradiometer targets throughout the remainder of 2012. Ground geophysical surveys will be performed if necessary to refine some gravity targets.

Figure 3 – Land tenure map showing the location of optioned properties in the Bathurst Mining Camp


Butler Project – Exploration Overview with Geophysics

Posted by on Tuesday, 14 February, 2012

MacDonald Mines Exploration Ltd. provides an exploration update in the mineral-rich Ring of Fire region of the James Bay Lowlands.

MacDonald began exploring in the Ring of Fire starting in 2003, shortly after the first volcanogenic massive sulphide (VMS) discovery at McFaulds Lake by Spider Resources and KWG Resources. The McFaulds VMS discovery is characterized by very high-grade intersections of VMS mineralization (McF-04-57 intersected 18.8 meters of 8.02% Copper (Cu), Mc-03-18 averaged 4.83% Zinc (Zn) over 25.75 meters) and at 250 meter-plus depths.

Exploration in the James Bay Lowlands is challenging due to the area being almost entirely a wetland. As a result, there is minimal outcrop, helicopter support is required and exploration time lines are longer. Over $18 million dollars has been spent to date on the Butler property and we have discovered six zones of multi-element mineralization with copper-zinc VMS systems, vandiferous titano-magnetite and magmatic nickel sulphide. This was accomplished through comprehensive exploration programs including geophysics, diamond drill holes and geochemistry.

Magnetic map (TF) of the Butler Property showing the location of identified multi-element, mineralized zones.

The lack of outcrop requires that a significant amount of attention and detail has to be paid to the geophysical techniques used in the area. Historically the programs focused on shallow targets; however down-hole surveys, ground magnetic and gravity surveys have indicated that the potential deposit(s) of interest lies deeper in the structural sequence.

A comprehensive suite of geophysical tools has applied at Butler:

Airborne EM, Magnetics & Gravity

  • 2004 VTEM – 2138.9 line kilometers of data were collected
  • 2008 VTEM – 1325.6 line kilometers of data were collected
  • 2010 AeroTEM IV – 261 line kilometers of data were collected
  • 2011 HeliGeoTEM – 261 line kilometers of data were collected
  • OGS/GSC Airborne Gravity Gradiometer

Surface EM

  • Butler 1 – 13 line kilometers of data were collected
  • Butler 3 – 39.3 line kilometers of data were collected
  • Butler 5 – 12.5 line kilometers of data were collected
  • Butler 3, 5, 6, and 7 – 30.17 line kilometers of data were collected

Surface Magnetics

  • 7 Ground Magnetic surveys completed in 2011 covering 81.1 line kilometers

Down hole EM

  • 64 diamond drill holes probed and modeled

The Company is currently enhancing the geophysical model to include the geochemistry data results. Collectively, all of the above geophysical results have consistently shown that an electrically conductive unit with magnetic properties and high density lies below those prospective zones.  These are the characteristics expected from a sulphide rich zone.

Magnetic map (TF) of the Butler 3 area showing the location of the EM target and magnetic susceptibility anomaly

MacDonald’s upcoming drill program will focus on the Butler property: Prior to drilling, the targets will first be refined using a deep penetrating geophysical method, similar to that used to detect the HudBay – Lalor deposit at Snow Lake, Manitoba.


The airborne TEM survey in the Northern Territory of Australia

Posted by on Thursday, 1 September, 2011

Crocodile Gold Corp. announces that a major airborne geophysical survey consisting of more than 4,000 line kilometres over priority prospective areas has been completed on schedule. The airborne survey used Geotech’s VTEM helicopter-borne system to scan Crocodile Gold’s extensive tenements in the Northern Territory of Australia. Southern Geoscience of Perth Australia was retained to ensure quality control, commutation, and detailed interpretation of the results.

Mark Edwards, General Manager of Geology and Exploration, commented: “The VTEM survey that we have completed is a state of the art geophysics system what provides deep penetrating information on the ground surveyed. It is used worldwide as a fundamental exploration tool to define geophysical signatures of mineral deposits and their hosts. Crocodile Gold selected the VTEM system to identify anomalies that will indicate the potential to discover further gold and base metal deposits within our land package. For example, it is known that the Cosmo deposit will produce a relatively strong electromagnetic (EM) signature with a coincident magnetic anomaly. The recently completed survey has clearly defined the hosting geological environment and numerous newly identified Cosmo “look-a-like” targets that will need investigation by our exploration team”.

The base metal environment represented by the Iron Blow and Mt. Bonnie deposits were also tested. Both deposits were clearly defined by the survey and a number of other newly defined VTEM anomalies lying in a similar stratigraphic position were identified. Further exploration investigation will be carried out for their Base and Precious (Gold/Silver) metal potential.

Five separate areas were flown within the Burnside Project area close to existing operational infrastructure and a significant part of the Moline Property (located 60 kilometres from the Union Reefs Mill) was also tested with the VTEM system.  The known gold and base metal deposits and hosting geology/structures of the Moline area were not clearly understood from historic data. The VTEM survey clearly defined the local stratigraphy and the exploration team will use this information to focus its efforts in defining additional significant gold mineralization in the area.

At Maud Creek, the initial planned survey area was expanded after the Company applied to significantly increase its land position in this region. Crocodile Gold now has a better understanding of the underlying geology and structures which host the significant Maud Creek gold deposit. The Company is currently gearing up its exploration efforts in this area in order to apply the knowledge gained from the VTEM survey and determine if other potentially significant gold deposits exist in this region.

Crocodile Gold’s exploration group has started initial ground investigation of a number of the VTEM anomalies generated from the survey. A land-based mapping and geochemical investigation program is underway with initial results are expected in the near future. This work will continue for the rest of the year.

Bill Nielsen, Crocodile Gold’s Vice President of Exploration stated: “I am very pleased with the results we have obtained from the airborne survey. The information will be very valuable in assisting with our ongoing exploration programs to explore our vast exploration asset base. There will be many months of ground follow-up work required to assess the many attractive and varied targets produced by the VTEM survey. We fully expect that future exploration success will result from this work”.

To view the maps associated with this information visit the following link: http://media3.marketwire.com/docs/crk_fgs_831.pdf


Deep penetrating geophysical survey in Mexico

Posted by on Saturday, 4 June, 2011

Canasil Resources Inc.  announces that results from the recently completed ZTEM airborne geophysical surveys have outlined encouraging targets at the Company’s 100% owned Salamandra and Victoria projects in Durango State, Mexico. The ZTEM geophysical surveys at both projects have highlighted well developed structures which are possible locations for structurally controlled mineralization. These areas exhibit complex electromagnetic and magnetic signatures, which have the characteristics associated with intrusive sources, and are coincident with prospective local geology and geochemical surface anomalies defined by prior surface mapping, sampling and drill programs. These combined features have defined large targets for further exploration. A summary of the results at each project is included below for reference.

Bahman Yamini, President of Canasil, commented: “We are very pleased to see clearly defined and prominent geophysical signatures from the ZTEM surveys at Salamandra and Victoria projects. These provide significant high potential targets for follow up at these two large projects, both strategically located close to the city of Durango in a highly prospective mineralized belt in Durango and Zacatecas States, Mexico, hosting major silver and base metal mines. We look forward to further exploration programs to advance these projects.”

Salamandra Project:

The recently completed ZTEM geophysical survey on the Salamandra Silver-Zinc project in Durango State, Mexico, has outlined a large complex area, measuring 2.5 km by 3.0 km, with low resistivity and flat magnetic response, interpreted to be an intrusive source. This is located east of and flanking the previously drilled Salamandra mineralized zone. The interpreted intrusive source is bounded by a north trending large regional fault on the east, and crosscut by several east–west fault zones. According to Frank Fritz, Canasil’s consulting geophysicist: “these are favourable locations for structurally controlled mineralization”.

Previous drilling on the western flank of the interpreted intrusive source intersected wide zones of calc-silicate skarn with disseminated silver-zinc mineralization, averaging 0.5% – 1.0% zinc and 5 g/t – 20 g/t silver, and  high-grade silver-zinc sulphide filled structurally controlled breccia zones grading up to 20% zinc and 300 g/t silver.

The interpreted intrusive source outlined by the ZTEM survey is alluvium covered and has not been drill tested. There is excellent potential in this area to outline disseminated mantle replacement or high-grade breccia associated silver, zinc and copper mineralization related to acid quartz porphyry intrusives, similar to the large San Martin mine of Grupo Mexico, located 80 km to the southeast. Follow up surface mapping, geochemical and ground geophysical surveys are planned to further explore this high potential target.

Victoria Project:

The deep penetrating ZTEM geophysical survey on the Victoria project, located 25 km northeast of the Salamandra project, has outlined a target similar to that seen at Salamandra. The ZTEM survey has outlined an area of complex low resistivity and low magnetic response measuring 2.0 km by 2.5 km, indicating a large intrusive source at depth. Numerous zones with small workings of oxidized sulphides with anomalous lead, zinc, gold, arsenic and antimony are observed at surface associated with silicified and skarn altered sediments and small intrusives located immediately north, east and west of the outlined geophysical target. Several strong northeast and east-west trending shear structures are present similar to the Salamandra project target.  The geophysical target outlined at the Victoria project has the potential to be a large massive sulphide skarn mantle mineralized system similar to the San Martin base metal mine of Grupo Mexico located 80 km to the southeast. A follow up program of geological mapping, rock and silt sampling and ground geophysics is planned.

The ZTEM airborne geophysical surveys were conducted by Geotech Ltd. The data was processed and provided by Geotech Ltd. The interpretations of the geophysical data were carried out by Frank Fritz, consulting geophysicist, and Gary Nordin, P. Geo., Director of Canasil and a qualified person under NI43-101. The surveys were flown with 10 km line length with a spacing of 200 metres. The Salamandra survey covered 617 line-kilometres over an area of approximately 120 square kilometers. The Victoria survey covered 680 line-kilometres over an area of approximately 130 square kilometers.

The Salamandra project is located 35 kilometres to the northeast of the city of Durango and covers 14,719 hectares, over 140 square kilometres. This large claim area is strategically located within the major silver-gold trend running through Durango and Zacatecas States, and is directly on trend with a number of important operating mines and recent discoveries. The project benefits from excellent access and infrastructure for mineral exploration and development. Prior geophysics and diamond drilling completed by Canasil has identified significant zinc-silver mineralization at Salamandra, with preliminary metallurgical tests showing high zinc and silver recoveries to clean concentrates. The project is located on the mineral-rich Fresnillo geologic trend, approximately 80 km northwest of the San Martin mine of Grupo Mexico, which is the largest underground zinc-copper-silver mining operation in Mexico, producing at approximately 6,000 tonnes per day.

The Victoria project covers a large prospective area of 60,000 hectares, 600 square kilometers, located 60 km northeast of the City of Durango and 25 km northeast of the Salamandra project. The project is centrally located on the same mineral rich trend, stretching from the northwest to the southeast through Durango and Zacatecas States, with excellent access and infrastructure. Initial reconnaissance, including geologic mapping and surface sampling by Canasil in the Victoria project area, has outlined prospective target zones, which were tested by the ZTEM survey. Located on a major mineralized trend, the very large project area is highly prospective for discovery of new mineralized systems.


Reflection seismic for base metals

Posted by on Thursday, 10 February, 2011
Darnley Bay Resources Limited is currently preparing for the 2011 drilling program for base metals at its Paulatuk Property in the Northwest Territories. Two drill campaigns are planned, in winter/spring and summer/fall 2011. CEO Reford is currently in Paulatuk to lay the ground work for local hiring and to fine-tune the logistical aspects of the drilling. A reflection seismic survey is planned in February/March over drill targets to assess overburden conditions and optimize location of drill collars.
Darnley Bay Resources and Diadem Resources have an exploration partnership on the Franklin Diamond Project located on the Parry Peninsula, Northwest Territories.  Diadem has reported the following progress:
“A total of five diamond drill holes totaling 707.6 metres in length were drilled during August 2010 to test four (4) negative ground magnetic anomalies (anomalies MT112, MT113, MT102 and MT10) in an area where kimberlite intrusives were discovered in an earlier exploration program carried out in 2000 and 2001. One of the magnetic anomalies was tested with two holes.  In addition, ground-based total field magnetic surveys were carried out over three separate grids to evaluate anomalies detected in an earlier airborne magnetic survey carried out by Diadem.  As a result of this drilling, 3 new kimberlite intrusives were discovered. A single hole to test anomaly MT113 failed to intersect any evidence of kimberlite in the core.

Updates on Exploration Program on Wabassi

Posted by on Monday, 24 January, 2011

Northern Shield Resources Inc. announces that field crews are being mobilized to the Wabassi property to prepare for ground and down-hole EM and magnetic surveys that will be used to prioritize several targets that have been selected for diamond drill testing that is planned for early February. The focus of the geophysics and drill program is a very strong and large, magnetic and VTEM anomaly identified by an airborne survey carried out subsequent to the initial drill program at Wabassi during May of last year. This anomaly (Anomaly ‘E’) is 500 meters in length and 70 meters thick. Two other new conductors defined by ground geophysics completed last spring will also be tested in the A1 Zone along with anomaly “C” which now can be traced for approximately 1 kilometer along strike (see Northern Shield’s website for maps and details). The size and scope of the drill project will depend, amongst other things, on the geophysical modeling.

Modeling of the Max geophysical data has identified a subtle but significant VTEM conductor on the southern fringe of the Max peridotite body. It is associatedwith an irregular shaped
magnetic trend that may represent a feeder conduit from the peridotite. Further west along this possible conduit is a zone of higher magnetism that correlates to a possible “IP
Effect” from the VTEM survey. This suggests the presence of possible disseminated sulphides. This target may be akin to Magma Metals PGE deposit near Thunder Bay which is also
hosted in a narrow conduit in association with disseminated sulphides.

The geophysics and diamond drilling programs are being funded by Discovery Harbour Resources Corp. under the option agreement whereby Discovery has the option of earning a 51% interest in the Wabassi property by incurring $3.4 million in exploration expenditures by March 2012.  Prior to the current exploration programs, Discovery had spent $1.7 million towards its earn-in.

Northern Shield also announces that the drill program at Max was frustrated and delayed by on-going technical difficulties largely brought about by the repeated failure of a single component of the drill. The program was suspended part way through the third drill-hole by Northern Shield until the cause of the failures could be determined and the problem rectified. The first hole drilled, targeting a discrete VTEM anomaly that management believes coincides with a feeder conduit, also deflected off-course and passed over the top of the anomaly. Northern Shield has since been informed by the drilling company that the problem has been remedied and as such Northern Shield looks forward to returning to the area.

The Wabassi Property is located in north-western Ontario, 60 km south of the Highbank Lake project and 100 km south of the Ring of Fire Ni-Cu-PGE and Chromite deposits. The property is being explored for reef-hosted PGE and massive sulphide Ni-Cu-PGE deposits and Cu-Zn-Ag-Au volcanogenic massive sulphides (VMS). The proposed railway route which will access the Black Thor and Black Label chromitite deposits in the “Ring of Fire,” now owned by Cliffs Natural Resources, passes very to the Wabassi property.



Updates on Exploration Programs in north-western Ontario

Posted by on Thursday, 20 January, 2011

Northern Shield Resources Inc. announces that field crews are being mobilized to the Wabassi property to prepare for ground and down-hole EM and magnetic surveys that will be used to prioritize several targets that have been selected for diamond drill testing that is planned for early February. The focus of the geophysics and drill program is a very strong and large, magnetic and VTEM anomaly identified by an airborne survey carried out subsequent to the initial drill program at Wabassi during May of last year. This anomaly (Anomaly ‘E’) is 500 meters in length and 70 meters thick. Two other new conductors defined by ground geophysics completed last spring will also be tested in the A1 Zone along with anomaly “C” which now can be traced for approximately 1 kilometer along strike (see Northern Shield’s website for maps and details). The size and scope of the drill project will depend, amongst other things, on the geophysical modeling.

The geophysics and diamond drilling programs are being funded by Discovery Harbour Resources Corp. under the option agreement whereby Discovery has the option of earning a 51% interest in the Wabassi property by incurring $3.4 million in exploration expenditures by March 2012.  Prior to the current exploration programs, Discovery had spent $1.7 million towards its earn-in.

Northern Shield also announces that the drill program at Max was frustrated and delayed by on-going technical difficulties largely brought about by the repeated failure of a single component of the drill. The program was suspended part way through the third drill-hole by Northern Shield until the cause of the failures could be determined and the problem rectified. The first hole drilled, targeting a discrete VTEM anomaly that management believes coincides with a feeder conduit, also deflected off-course and passed over the top of the anomaly. Northern Shield has since been informed by the drilling company that the problem has been remedied and as such Northern Shield looks forward to returning to the area.

The Wabassi Property is located in north-western Ontario, 60 km south of the Highbank Lake project and 100 km south of the Ring of Fire Ni-Cu-PGE and Chromite deposits. The property is being explored for reef-hosted PGE and massive sulphide Ni-Cu-PGE deposits and Cu-Zn-Ag-Au volcanogenic massive sulphides (VMS). The proposed railway route which will access the Black Thor and Black Label chromitite deposits in the “Ring of Fire,” now owned by Cliffs Natural Resources, passes very to the Wabassi property.

Read more: http://www.digitaljournal.com/pr/203531#ixzz1BayJRxkO


Drill testing of AEM anomalies with success

Posted by on Monday, 17 January, 2011

Australian  uranium  company Cauldron Energy Ltd. has completed a reverse circulation (RC) drilling program targeting base metals at the Company’s 80% owned Beadell Project in Western Australia. The  1,702m  drilling  program focused on one of two Tempest AEM targets within the  base metal rich  Rudall Complex of Western Australia.

Interpretation and analysis of the project geology and ground and airborne geophysical data, including ground based gravity, regional magnetic surveys and Tempest  AEM identified two significant conductive zones that are anomalous to the regional geology. The two AEM anomalies, which are linked by a large north trending regional fault system, show features that are consistent with what could be expected from massive sulphide mineralisation.
The recent drilling program comprised a  total  of  six Reverse Circulation (RC) holes for 1,702 metres, targeting the southern “bulls-eye” AEM anomaly. The drilling, on 200m x 100m and 200m x 200m spacings, intersected a dominant high grade amphibolite facies with zones dominated by garnets and epidote as well as common quartz veining associated with broad zones and veins of  disseminated sulphides, predominantly comprised of pyrite and chalcopyrite. A number of weakly graphitic zones were identified within the central part of the drill pattern, which appear to be associated with  north trending  fault zones.  These graphitic zones were often associated with zones of massive pyrite. Drilling along the eastern side of the pattern intersected thin to massive zones of orthogneiss to monzogranite rocks near the base of the drill holes. A number of significant results were returned from the drilling, including individual narrow higher grade zones  of copper and gold associated with  broad zones of anomalous  lead and zinc mineralisation, including  28 metres at  1794 ppm  lead  and 2045 ppm zinc in hole BRDC 003.
Interpretation of the results indicates that the source of the geophysical anomaly identified by the AEM is below the extent of the current drilling and remains to be tested by deeper drilling. Surface geochemical sampling programs and down-hole EM surveys are planned to commence in Q1 2011, to further define the target for follow-up drilling programs.

Athabasca Basin – geophysics underway

Posted by on Wednesday, 29 December, 2010

Virginia Energy Resources Inc.  reports that it has approved a 12-hole, 2300-metre drill program on the Richardson-Crooked Lake target on the Hatchet Lake property in the Athabasca Basin of Saskatchewan.

The drilling is planned for February 2011 and will be preceded by a ground-based Horizontal Loop Electromagnetic (HLEM) survey to refine the position of several shallow conductor targets. The Richardson-Crooked Lake area is located 20 km north of the Tuning Fork target where the JV partners identified unconformity-style mineralization in a winter 2010 drill program (see Virginia News Release of June 29, 2010). In addition, the JV partners plan ground geophysical surveys in 2011 on the adjacent Murphy Lake property.

The 2011 drilling and geophysical survey will target a historically described, six-kilometre-long conductor system with uranium and base-metal enrichment associated with sulphide mineralization and alteration in sandstone and basement rocks. The Richardson-Crooked Lake target is located on the shallow northeast margin of the Athabasca Basin with depths to the basement contact targets varying from zero to 120 metres, well within the limits of low-cost open-pit mining.

While there has been considerable historic drilling in this area, most of the holes were vertical and did not effectively test the steeply dipping conductors. Nevertheless, a number of historic uranium and polymetallic base-metal (Co, Cu, Ni, Zn, As, Au) drill intercepts were reported, including SMDC Hole 61 which intersected “uraniferous sulphide breccia” which assayed 7.34% Co, 1.66% Ni and 16.07% As over 2.5 m (and 5.0 m of 73 ppm U), Hole 74 which intersected 2,112 ppm U, 256 ppm As and 202 ppm Ni over 3.4 m, and Hole HT-96 which intersected 2,600 ppm U over 1.0 m plus adjacent sections which assayed 5.95% Cu over 2 m and 0.612% Co over 2.5 m. The association of uranium with very high base-metal values is very encouraging as it is typical of the “polymetallic” class of sandstone-hosted deposits such as Cigar Lake, Roughrider and the Sue A, B, and E deposits. Most of the holes in this area did not extend far below the unconformity, and therefore, did not adequately test for mineralization in the basement rocks.

The 39,930-hectare Hatchet Lake property is located 25 km north of Points North Landing, and 17 km north of the McClean Lake mill owned by AREVA-Denison-OURD. The target is an unconformity-type or basement-hosted uranium deposit at or near the contact between the Athabasca sandstones and underlying basement rocks. The Hatchet property includes faults and conductors similar to those that host nearby unconformity-related uranium deposits and prospects such as Jeb (Areva-Denison-OURD), Dawn Lake and La Rocque Lake (Cameco-Areva-JCU), Moonlight (Areva-Denison-JCU), Midwest (Areva-Denison-OURD) and Roughrider (Hathor-Terra). For additional background see the Virginia’s February 16 and June 29, 2010 news releases, as well as property maps at www.virginiaenergyresources.com.


Extending Gold And Base Metal Potential with 3D IP survey

Posted by on Tuesday, 10 August, 2010

Indonesian-focussed Robust Resources has revealed that a 3D IP-Resistivity survey over the flagship Lakuwahi target, as well as new drilling results, have significantly extended the discovery target zones and therefore the gold and base metal resource potential on Romang Island.

The IP-Resistivity geophysical survey commenced on 24 March 2010, and field data collection is 50% complete, with 20% of information processed and modelled.

The geophysics and drilling has confirmed a well-defined geophysical (resistivity) anomaly area that is 20-times larger than current Batu Mas drilled prospect and remains open.  Importantly, there appears to be continuity of precious and base metal mineralisation structure confirmed between main drilled prospects of Batu Mas and Batu Hitam (over 2 kilometre strike length).

Recent drilling at Batu Mas and Batu Hitam continue the strong track record of results with thick intersections of precious metals and base metals on both prospects. In total, results for fourteen holes have been received, eleven of which intersected mineralisation of potential economic significance.

Managing director Gary Lewis said, “In this latest stage of our exploration program, Robust has done the reverse of most companies in that we have drilled prior to embarking on the geophysical studies which puts us in the now fortunate position of being able to calibrate the geophysics with drilling data.”

“Based on the excellent correlation of geophysical anomalism with the drilling data, the results have not only extended the Batu Mas target zone by around 20-times its current size, but also demonstrated that the geophysical anomaly clearly links the Batu Mas and Batu Hitam prospects, he said.”

“Whilst the Company had long suspected that this was the case, these latest results provide us with more confidence to move towards defining a maiden JORC resource from these two prospects alone. In addition, the IP has also identified a number of new drill targets, in particular those hidden under limestone cover, which we will shortly begin to target with our four owner-operated rigs.”

Batu Mas

Results for nine diamond drill holes have been recently received, with seven of the holes with coincident geophysical anomalism intersecting precious and / or base metals of potential economic significance. The very close fit between the drilling results at Batu Mas and the resistivity anomalism is especially significant, both in relation to validating the geophysical methodology and for demonstrating the extent of the potential resource at Batu Mas. The positive drilling results (both gold/silver and base metals) are all contained within the geophysically defined 50 Ohm-m contour, which concurs closely with the grade-thickness.

Gary Lewis continued, “The correlation of the positive drilling results and the resistivity represents a valuable enhancement of our understanding of the Lakuwahi mineralisation. We now have confidence that the extensions to the Batu Mas mineralisation and the new targets indicated by the resistivity, which so far is indicated to be in the order of 20-times the size of the Batu Mas area itself, are indeed likely to contain significant precious metal and base metal mineralisation.
Robust’s current drilling plan has been modified in light of the new results and testing of the Batu Mas
North target has already commenced.”


Snow Lake projects under support of geophysics

Posted by on Thursday, 28 January, 2010

One of the known volcanogenic massive sulphide (VMS) districts is  Snow Lake which is located in central Manitoba. The VMS mineralization is associated with juvenile rocks of the Flin Flon greenstone belt. The belt is one of the most prolific VMS belts and the largest Paleoproterozoic VMS district in the world. There are several recent examples of geophysical supporting of the exploration programs on the region.

At the end of last year Rockcliff Resources Inc. announced that Geotech Ltd. of Aurora, Ontario has commenced a 3,000 line kilometre airborne survey on the Company’s Snow Lake VMS Project. The ZTEM survey focused on Rockcliff’s Squall and Tramping Properties. Both properties are located approximately 6 km north and south of HudBay’s recently discovered (2007), buried Lalor Deposit where recent deep drilling intersected a new gold/copper zone grading 34.5 m of 5.33% copper and 13.35 g/t gold. The survey also covered Rockcliff’s five near surface copper-rich deposits and additional areas with VMS potential. The survey has the capability of locating conductive bodies down to depths of over a kilometer.

The purpose of the survey was to integrate Rockcliff’s existing VTEM database (13,000 line km) on the project with Geotech’s state of the art ZTEM geophysical technology. The combined surveys allows for complete geophysical coverage and locate conductors buried from near surface to depths in excess of a kilometre. All conductors identified in the survey prioritized based on their conductivity, resistivity and proximity to juvenile arc rocks.

The survey utilized Geotech’s ZTEM or Z-Axis Tipper Electromagnetic system, an innovative airborne EM system which uses the natural or passive audio frequency fields of the Earth as the source of transmitted energy.

Now Rockcliff Resources Inc. announces the drilling program. A minimum of 5,000 metres (m) of drilling are planned in approximately 30 holes. Drilling is planned on the Rail, Reed, Freebeth, Tramping and Squall properties. The targets include extensions of a known copper-gold rich horizon (Rail), additional testing of DPEM & BHPEM anomalies (Reed), an untested borehole anomaly (Freebeth) and untested, buried ZTEM targets (Tramping and Squall). Drilling at the Reed property will focus on a series of deep, off-hole anomalies indicative of multiple, stacked, highly conductive lenses with conductivities typical of massive sulphide mineralization. Four off-hole anomalies at vertical depths of 500 m, 750 m, 880 m and 930 m will be tested.

VMS Ventures Inc. has completed  its diamond drill testing of phase one targets, at the Tower Zone, on  its 100% held Reed 5188 and Reed 5196 claims.  The program consisted of three holes and the extension of a previous hole for a total of 1809 metres.   Diamond drill hole (TZ-08-01) was extended to assess a Borehole Pulse Electromagnetic (BHPEM) anomaly. All drill holes intersected sulphide mineralization explaining the Surface Pulse Electromagnetic (DPEM) and coincident Versatile Time-Domain Electromagnetic (VTEM) anomalies. The Super Zone has been defined on the basis of “AdTau” (see image 2), which is a calculated measurement derived from the analysis and interpretation of VTEM data. AdTau is a direct indication of rock conductivity. The metal-rich mineralization that comprises VMS-type deposits typically produces strong conductivity responses. The 550 hectare Reed Lake Super Zone is interpreted to be highly prospective for this style of deposit. The Company is building its Super Zone exploration plans based on the hypothesis that it may host a VMS camp of several deposits.

Deep-EM and Magnetic Survey Results Map

Troymet Exploration Corp.  announces the commencement of its winter program on the McClarty Lake project located near Snow Lake, Manitoba. The property lies ~45 km south of HudBay Minerals’ Chisel Lake and Lalor Lake volcanic massive sulphide (VMS) deposits.

The establishment of a 10.6 km grid on Troymet’s 100% owned MAC 3 claim is expected to be completed this week, followed by a fixed large loop surface pulse electromagnetic (PEM) survey under contract to Crone Geophysics of Mississauga, Ontario. The grid is centred over the Mac EM conductor that was identified by the Company’s 2008 deep penetrating VTEM helicopter-borne survey and is on trend with the Discovery zone.

The Mac conductor is a high priority target that offers the potential for immediate and significant new VMS discoveries on 100% owned Troymet ground. A 2010 winter diamond drilling program (~1,500 metres) is planned to follow up on results of the PEM survey.


Wildcat’s EM targets are drilled

Posted by on Monday, 11 January, 2010

The Wildcat project is located 90 kilometres west of Watson Lake, in the Rancheria District of southern Yukon, Canada.  1,940 hectares in size (19.4 sq km), widespread silver-lead-zinc mineralization occurs across the property. Mineralization on the Wildcat was discovered in the early 1940s where early work focussed on a series of narrow, high-grade argentiferous galena veins and fracture filings, hosted primarily within dolomite and limestone.  More recent work, including diamond drilling in the mid 1980s, was directed at the ‘Main Zone’, a zone of manto-style silver-lead-zinc mineralization.

From 1983 – 85 most work tested a large gossan zone in the central part of the property (the Main Zone). Butler Mountain Minerals completed a Pulse EM survey over the gossan zone and identified a strong, 600 meter long, north-northeast trending conductor. From 1983-85, 35 diamond drill holes were drilled, the majority of which tested this target. Drilling successfully intersected multiple zones of massive pyrrhotite-sphalerite mineralization, with results including 12 feet grading 6.2% Zn, 1.09 oz/t Ag and 0.32% Pb (ddh 83-3), 7 feet grading 5.06% Zn and 9.86 oz/t Ag (ddh 83-6), and 10 feet grading 11.58% Zn, 1.05 oz/t Ag and 0.7 % Pb (ddh 85-10).

During 2008, Killdeer Minerals Inc. completed a horizontal loop electromagnetic (HLEM) survey over the central portion of the Wildcat property. The purpose of the survey was to confirm, re-locate and better define the EM conductor at the Main Zone, as a guide to subsequent drilling, and to test for other conductors elsewhere on the property.

Seven HLEM conductors were identified by the Killdeer Minerals’ 2008 survey. Two of these anomalies are high priorities for follow-up, anomaly H-A (the Main Zone anomaly) and anomaly H-F (1 kilometer to the northwest of H-A) on the lower east flank of Little Guy Hill.

The Main Zone HLEM anomaly is a 1200 meter long, complex north-northeast trending conductor, which is coincident with Pulse EM and VLF-EM conductors identified by previous surveys and with a significant positive magnetic field response. Based on the geophysical response, two styles of mineralization are interpreted, a north-northeast trending, steeply west-dipping mineralized fault zone and, east of this, moderate east-dipping conformable sulfide mineralization, on the east flank of an anticlinal structure. The associated positive magnetic field response results from the pyrrhotite-dominant mineralization. While the fault-controlled mineralization is well tested by previous drilling, drilling has been poorly oriented to test for east-dipping mineralization east of the fault. This is a high priority for follow-up drilling. The other high-priority target for follow-up drill testing is a 200 meter long, north-northeast trending HLEM conductor, also with an associated positive magnetic response, located 1 kilometer to the northwest of the Main Zone in an area of widespread manganese gossan and elevated soil geochemistry.

One of the 2009 drill holes tested a HLEM conductor related to a distinct tectonic zone situated approximately 900 metres east from the Main Zone. At shallow depth the hole intersected a very strongly leached, stratabound zone of limonite-hematite mineralization enriched in base metals related to paleo-karst settings. The hole did not reach target depth and due to technical problems was prematurely terminated in a fault zone enriched in gold related to pyrite-chalcedony mineralization.
Additional geological mapping, soil sampling and electromagnetic surveys are required to identify other geological settings favorable for occurrence of manto-style mineralization of
better integrity prior to further drilling of the Wildcat property.

VTEM for copper-gold targets at Narracoota

Posted by on Thursday, 7 January, 2010

Australian Richmond Mining Ltd. has finished VTEM survey for exciting DeGrussa style copper-gold targets at Narracoota.

The Narracoota project comprises a 111km2 granted tenement located 70km north of Meekatharra, WA and 75km southwest of the significant DeGrussa copper-gold discovery.

Sandfire Resources’ DeGrussa copper-gold discovery appears to be a volcanogenic massive sulphide (VMS) deposit and is hosted within rocks of the Narracoota Volcanics.  Richmond Mining’s Narracoota project contains extensive widths of Narracoota Volcanics that are interpreted to occur in at least three structural repetitions, providing a target zone of approximately 20km in length.

Within the strike extension of the main structural repetition lays the Bilyuin magnetic anomaly.  This is a large magnetic feature (approximately 5km long and averages 1 km in width) associated with a volcanic breccia complex outlined in the southern part of the tenement from geophysical data and limited historic drilling.

The Bilyuin magnetic anomaly, coincident with a prominent regional gravity high, is interpreted to be an ancient volcanic centre and could be a possible heat source for the remobilisation of metals, if any are present in the area.  Consequently the breccia could be the ideal host for possible VMS style Cu-Au or Cu-Zn-Pb-Au-Ag systems.

An airborne versatile time domain electromagnetic (VTEM) survey has commenced to investigate the potential for DeGrussa style Cu/Au
mineralisation targets at the Narracoota project. The Narracoota tenement is largely covered by transported sediments and as a consequence has been lightly explored through modern exploration. Initial exploration for VMS-style Cu/Au mineralisation is based on using the latest technology VTEM geophysical system to locate conductive anomalies like those successfully delineated from trial reconnaissance ground EM surveying at Sandfire Resources’ high grade DeGrussa Cu/Au prospect. Sandfire subsequently flew VTEM over its tenements and identified a number of high priority targets concealed below transported cover.

The new discovery on base of 25 years old IP data

Posted by on Thursday, 7 January, 2010

Australian Paradigm Metals Ltd. has announced about continuing positive drill results at Kangiara discovery. The Kangiara project  has significant potential for combined gold – silver – base metal mineralisation. A drill program is in progress, and numerous strong gold-base metal intercepts have been made by the company.  Paradigm is targeting a large open pittable polymetallic resource at Kangiara. The polymetallic gold-lead-zinc-copper-silver mineralization is hosted by Silurian silicic volcanic rocks, near Yass, 250km from Sydney NSW. Sulphide mineralisation to date occurs within a steep dipping north-south striking structure 50 metres wide.  Exploration has discovered a lead-zinc-gold rich lens partly underlain by a gold-copper zone. The sulphide mineralisation occurs close to surface, and is partially overlain by an oxidised cap which contains high grade silver mineralisation. Sulphide mineralisation is dominated by sphalerite, galena, chalcopyrite, and pyrite. The picture illustrates map of IP chargebility on depth 100 m with drill holes and targets at the Kangiara project. Sulphide mineralisation has now been intersected along a continuous north‐south strike length of 350 metres. Based on the company’s geophysical interpretations, mineralisation could extend southwards along the structure for a further 650 metres.

Known mineralisation correlates well with geophysical IP anomalies – the IP data indicates mineralisation could extend for a strike length of 600 metres at shallow depths of <100m, and to depths of >150m in the central part of the prospect. Modeling of IP geophysical data acquired by a past explorer show a strong correlation between mineralisation in the drilling and IP chargeability anomalies. Figure 2 shows a longitudinal section of the drill holes with the IP chargeability anomalies highlighted in red, with a strong positive
correlation apparent. Two chargeability anomalies at either end of the trend are undrilled, and could extend the strike length of the Kangiara structure to 600m. “The IP geophysics is giving us an excellent targeting tool for our drilling, and is proving highly predictive of the mineralization so far” – says managing director.

The IP data was 3D remodeled using 3D geophysical software by Arctan Services Pty Ltd. The data was collected by Noranda (1985) with a 50m east‐west dipole‐dipole setup using a line spacing of 100m.


At the end of the year with geophysical expectancies

Posted by on Monday, 21 December, 2009

Hannans Reward Ltd., an explorer focused on prospecting for gold and base metals within Western Australia has conducted airborne VTEM and ZTEM (Geotech Ltd.) and detailed ground FLTEM.
Heli-borne geophysics (VTEM) has identified multiple, well defined and well located EM anomalies within the Forrestania Project.
Majority of the EM anomalies are located within the newly acquired Stormbreaker ground position. Hannans’ Managing Director Damian Hicks said, “The recently completed heli-borne survey (VTEM) within the Stormbreaker Prospect has been extremely successful, generating anomalies covering an aggregate strike length of 14km. Hannans can now focus its future ground based exploration activities on these discrete anomalies.” Importantly the majority of the EM anomalies are located within the newly acquired ground position, which has not previously been exposed to any modern nickel exploration. The previous owners were solely focused on gold exploration.
We also have a newly developed airborne geophysical technique (ZTEM) being trialled over the Stormbreaker Prospect to determine if any additional deeper EM anomalies can be identified. Once the current helicopter surveys are finished we’ll immediately start ground based geophysical surveys (FLTEM) to further refine the EM anomalies. This will also assist with 3D modelling of the anomalies in preparation for drill testing. With such a large number of EM anomalies, it is anticipated that this ground surveying will continue through December and into January 2010.”
The detailed FLTEM surveying will refine the 13 recently identified priority VTEM targets and is anticipated to be completed during January 2010. Upon receipt of the final FLTEM data, geophysical modelling and subsequent drill hole positioning can commence.