Posts Tagged VTEM

Airborne EM and ground IP geophysical anomalies – the new Significant Copper-Gold System in Panama

Posted by on Tuesday, 30 September, 2014

Pershimco Resources Inc. announces that the results of its recent exploration drilling on the Idaida target have confirmed a new copper-gold system. Importantly, this newly revealed system shows both near surface and deeper mineralized feeder structures analogous to the Company’s two main targets, La Pava and Quema Deposits, the latter of whose center is located 1.3 km north-west of Idaida.

HIGHLIGHTS OF THE IDAIDA DRILLING

  • Extends high-sulphidation alteration and mineralization to depth;
  • Intercepted an oxide gold zone and an underlying sulphide copper-gold zone;
  • Intercepted new high-sulphidation “feeder” zones at depth;
  • Both upper and lower ‘feeder” zones flank and dip towards the modeled airborne and ground IP geophysical targets.

Dual Reverse Circulation/Diamond drill holes (RC/DH), PRH13316/PDH135316 (’316′) and PRH13317/PDH135317 (’317′) are the deepest to date on the Cerro Quema project, and provide important information on the mineralization and alteration system at Idaida as well as other exploration targets within the concession. Both drill holes (’316 & 317′) intercepted sulphides commencing at 85 and 50 meters downhole respectively and both continued to show sulphides and alteration to their final depths. Intercepted “feeder” zone mineralization within both the upper and lower levels show similar intense alteration (acid leach – advanced argillic) and moderate to strong sulphide mineralization.

Of particular significance, the lower feeder structure intercepted by drill hole ’317′ which returned 58m @ 0.38%Cu was enveloped within a broader intercept of 95m @ 0.25%Cu. This intercept showed elevated sulphides (>6%) and hosted within an advanced argillic alteration zone containing pyrophyllite. The dominance of the advance argillic mineral pyrophyllite indicates a higher temperature setting typically found within the ‘root zones’ of high sulphidation systems.

These “feeder” structures are on the margins of and dip towards the airborne VTEM and ground IP chargeability geophysical anomalies.

Figure 1 below shows the drill hole location plan as well as the location of the IP Chargeability target. Furthermore, a short video demonstrating the location, size and geometry of the Idaida project’s IP chargeability anomaly is accessible at http://youtu.be/m8eXp0bsHkA.

During the first half of 2013, Pershimco completed important exploration activities on two new targets outside of the La Pava and Quema-Quemita deposits. This work included:

  • Idaida and Pelona were drill tested, returning significant copper and gold intercepts;
  • 7,195 meters of drilling (RC and diamond) completed;
  • 112.5 Line Kilometers of IP geophysics completed; and,
  • Commenced regional mapping and geochemical sampling program on additional exploration targets identified by previous airborne geophysics.

The Idaida drilling results are extremely exciting in terms of the significant grades and thicknesses of copper and gold mineralization intersected near surface as well as the discovery of additional feeder structures at depth. The exploration geophysics and geological modeling undertaken by the Pershimco Team is proving to be successful as more targets are being strategically identified and developed. As we have noted previously, this deliberate multi-staged approach continues to prove to be invaluable in building on the success our project,” said Alain Bureau, President and CEO of Pershimco.


Unlocking Australia’s hidden mineral potential with geophysics

Posted by on Friday, 1 August, 2014

Dr Richard Blewett:

“It is becoming increasingly difficult to discover near-surface mineral resources in Australia. New and innovative products and techniques are being developed as part of the UNCOVER Initiative to help attract mineral exploration investment that has the potential to lead to the discovery of new resources.”

One of the focus regions for the UNCOVER Initiative is the Thomson Orogen: “The Thomson Orogen is a large area that lies to the north and west of the Lachlan Orogen in New South Wales, South Australia, the Northern Territory and Queensland. Much of it is under the cover of younger sedimentary basins, with some up to several kilometres thick, and it is therefore a poorly understood element of Australia’s geology.

The southern Thomson Orogen is true ‘greenfields’ country. Although the mineral potential of the region is largely unknown, the northeastern Thomson Orogen (for example Thalanga, Charters Towers) and the similar-aged Lachlan Orogen to the south are well mineralised (for example Cadia, Northparkes, Lake Cowall Cobar). In order to attract exploration investment into the southern Thomson Orogen, and also to improve the geological understanding of the area, Geoscience Australia, the Geological Survey of Queensland and the Geological Survey of New South Wales have commenced a collaborative project to collect new (and synthesise existing) pre-competitive data.

One of the first steps in this collaboration is to acquire airborne and ground geophysical data including airborne electromagnetics (AEM), gravity and magnetotelluric (MT) data. Regional AEM data has now been collected to map cover thickness and assess the geology and prospectivity of the Southern Thomson Orogen across the New South Wales-Queensland border around Hungerford and Eulo. These data will be interpreted using existing borehole stratigraphic data and a new solid geology compilation of the region developed between Geoscience Australia, the Geological Survey of Queensland and the Geological Survey of New South Wales.

 

The Geotech VTEM FullWaveForm
airborne electromagnetic acquisition
system used in the Southern Thomson
Orogen airborne electromagnetics survey.
Image credit: Geotech Airborne Limited.

 

 

 Geoscience Australia is a leading promoter of AEM surveying for regional mapping of cover thickness, under-cover basement geology and sedimentary basin architecture. Geoscience Australia flew three regional AEM surveys during the 2006-11 Onshore Energy Security Program (OESP): Paterson (Western Australia, 2007-08); Pine Creek-Kombolgie (Northern Territory, 2009); and Frome (South Australia, 2010) [1]. The surveys were primarily designed to provide reliable, fit-for-purpose pre-competitive AEM data for mapping critical features of uranium mineral systems.

Results from these surveys have now produced a new understanding of the architecture of critical mineral system elements and mineral prospectivity for a wide range of commodities of these regions and includes details on the thickness and character of the regolith, sedimentary basins and buried basement terrains. The data have since been found suitable not just for uranium, but for mapping a range of other mineral systems including gold, silver, copper, lead, zinc and potash, as well as for under-cover geological mapping and groundwater resource estimation.

The survey data are now processed using the National Computational Infrastructure (NCI) facility at the Australian National University to produce GIS-ready interpretation products and GOCADTM objects suitable for 3D modelling.

A number of 3D models are being developed to interpret the near-surface under-cover geology of cratons and mobile zones, the unconformity surfaces between these and the overlying sedimentary basins, and the architecture of those basins. These models are constructed primarily from AEM data using stratigraphic borehole control and show how AEM data can be used to map the cross-over area between surface geological mapping, stratigraphic drilling and seismic reflection mapping. These models can be used by minerals explorers to more confidently explore in areas of shallow to moderate sedimentary basin cover by providing more accurate cover thickness and depth to target information. A 3D model of basement-cover relationships and depth of cover will be developed for the southern Thomson Orogen.”


Geophysical Survey helicopter in promotional filming at Elko Regional Airport

Posted by on Tuesday, 24 June, 2014

ELKOGeotech takes to the air to figure out what’s underground with its geophysical surveys.

On Monday, a AW-119 “Koala” helicopter and an 85-foot geophysical survey apparatus were at Elko Regional Airport to film promotional footage for Geotech. The film crew works for Cineplex, a company based in Canada.

Geotech specializes in airborne geophysical survey systems, according to Field Operations Manager Darren Tuck. The company’s clients are usually mineral exploration businesses that are interested in starting up a mine, and use the survey to find promising mineral deposits, including coal, silver, iron and copper.

Tuck said an apparatus carried by a helicopter will produce an electromagnetic pulse into the ground it flies over. Those pulses reflect off magnetic readers, and Geotech makes a map of the area after the process.

“It provides our client with a map of what the underlying layers of a structure looks like,” Tuck said.

Geotech is a global company based in Canada. Tuck said the company has worked for local mines, although he wouldn’t name any of the company’s clients in order to protect their confidentiality.

Tuck said the Elko airport was selected as the location to film Geotech’s equipment, known as Versatile Time Domain Electromagnetic surveying. Tuck said Geotech has more than 30 VTEMs. The apparatus comes in a variety of sizes.

For information, visit www.geotech.ca.


After airborne EM: 71 m of Sulphide Mineralization in Felsic Volcanics at Homer Lake

Posted by on Tuesday, 13 May, 2014

TerraX Minerals Inc.  has received assay results from the first four holes drilled during the recently completed winter drill program at Northbelt, Yellowknife City Gold Project. These holes were drilled at the Homer Lake base metal target, which is located within 15 km of the city of Yellowknife and just 2 km from the new Bluefish Hydro Dam opened in July 2013. Assay results from nine holes drilled on TerraX’s two top priority gold targets, Crestaurum and Barney Shear, are pending and will be reported in the coming weeks, with the summer drill program expected to begin in late June 2014.

Two holes, TNB14-003 and TNB14-004, where drilled to test the down dip extension of surface showings sampled by TerraX in 2013 (chip samples of 7.0m @ 0.50 g/t Au 90.2 g/t Ag, 4.25% Pb and 0.89% Zn) and intersected felsic volcanics that are pervasively mineralized including multiple massive to semi-massive sulphide zones.

 

 

 

 

 

==================================================================

 

Highlights include:

        
        --  71.15m @ 0.25 g/t Au, 14.0 g/t Ag, 0.73% Pb and 0.57% Zn in hole TNB14-
            004 (inclusive of 3.42m @ 3.41 g/t Au, 69.3 g/t Ag, 3.67% Pb, 3.17% Zn
            in massive sulphides) and
        --  60.87m @ 0.11 g/t Au, 10.4 g/t Ag, 0.58% Pb and 0.65% Zn in hole TNB14-
            003;
               
===================================================================================
The Homer Lake drill program was designed to test a 400m-500m long VTEM (electromagnetic) anomaly with an interpreted steep westerly dip that had been identified by airborne surveying in 2013 and continues for a further 1km as a weaker VTEM anomaly to the south. 

Two holes (TNB14-001 and TNB14-002) were drilled with an easterly azimuth on sections 100m apart and designed to intersect the northern end of the anomaly. Holes TNB14-003 and 004 were drilled to the east of the anomaly in an area where base metals were identified in historic trenches during 2013 field work (eg. chip samples of 7.0m @ 0.50 g/t Au 90.2 g/t Ag, 4.25% Pb and 0.89% Zn). A map showing the location of these drill holes is available on our web site atwww.terraxminerals.com .

Higher grade intervals occur within the mineralized felsic volcanic unit, and also in the adjacent mafic volcanics (see table). Within TNB14-004 these include 3.42m @ 3.41 g/t Au, 69.3 g/t Ag, 3.67% Pb and 3.17% Zn within felsic volcanics; and 5.31m @ 0.40 g/t Au, 64.5 g/t Ag, 3.65% Pb and 2.64% Zn at a felsic to mafic volcanic contact. Within TNB14-003 high grade intervals include 4.44m @ 0.16 g/t Au, 25.5 g/t Ag, 2.10% Pb and 2.59% Zn at a mafic to felsic volcanic contact; 1.50m @ 1.70 g/t Au, 43.3 g/t Ag, 2.41% Pb and 2.04% Zn in felsic volcanics; and 2.02m @ 0.34 g/t Au, 85.1 g/t Ag, 4.08% Pb and 3.72% Zn at a felsic to mafic volcanic contact.

Joe Campbell, P.Geo, President of TerraX, states “The mineralization drilled in holes TNB14-003 and TNB14-004 is located along one of six sub-parallel zones of mineralization identified by TerraX in field work during the summer of 2013. Several of these zones have been traced over hundreds of meters of strike length on surface. While the high-grade gold targets at Northbelt remain our top priority, these wide zones of mineralization, coupled with the higher grade intervals of massive sulphides, are indicative of a large precious metal-rich base metal mineralized system in the Homer Lake area that definitely warrants further exploration when time and resources permit.”


Complex interpretation of geo data for Eskay Creek style mineralization in BC

Posted by on Tuesday, 6 May, 2014

Dolly Varden Silver Corporation announces the results from its geophysical program at the Dolly Varden property in Northwestern BC. The geophysical models further confirm drill targets for the Company’s proposed 2014 drill program and identify several new targets.

The newly compiled geophysical data outlines key horizons at depth and other surface anomalies that are coincident with known mineral showings, geochemical and structural targets already identified on the Dolly Varden property.

Dolly Varden

The combination of airborne MAG, VTEM, ZTEM radiometric, and geochemical data, along with geological and structural mapping, was used to define priority target zones. These helped define steep linear features, syngenetic faults, lithologic contacts related to basin formation, and key fluid controlling structures. In addition, key rock units, contact zones and alteration zones most likely to be associated with mineralization, were identified.
This compilation has demonstrated that the known deposits, showings, and related alteration zones are all located within a rift setting. The key rock units that infill the rift have also been identified, and these represent viable targets for Eskay Creek style VMS mineralization. Drilling will be conducted within corridors where mineralized occurrences and coincident alteration haloes point to extensive hydrothermal fluid flow. The key target areas for 2014 drilling include syngenetic VMS-style mineralization and associated feeder structures.

To view the image accompanying this press release, please visit the following link: http://media3.marketwire.com/docs/DV506-F1.pdf or visit www.dollyvardensilver.com.

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The review of all available geophysical models identified six targets that are being recommended for follow-up work. Three of these targets are new and are located near the northern boundary of the Dolly Varden property and three of the identified targets confirm existing targets that are already scheduled for drilling in 2014.

The geophysical data adds information about the geometry and outlines the contacts between two key geologic horizons. In particular, the geophysics tracks the DVT Horizon to the north and under the Red Point area. Prior drilling on the DVT Horizon has intersected high grade silver mineralization that remains open to the north. The geophysics was also successful in outlining the Salmon River Formation that is prospective for Eskay Creek style mineralization. The geophysical results are congruent with, confirm, and add additional information to the targets slated to be drilled in 2014.

Further, the geophysical results indicate several new targets that have the potential for additional Eskay Creek style accumulations. These newly developed targets are located on the underexplored northern section of Dolly Varden’s property. The area is several kilometers to the North from the existing historical workings and abuts neighbouring exploration properties controlled by Homestake Resource Corporation and the Homestake – Agnico Eagle Mines joint venture.

The three targeted corridors are the 1) Torbrit-Red Point Corridor – following known silver mineralization underneath Red Point, an Eskay-Creek style target; 2) Musketeer Corridor – which runs along the east side of the Kitsault river with numerous Ag-rich epithermal vein-type showings with strong potassic radiometric signatures; and 3) Wolf-Surprise Corridor where an Eskay-Creek style host formation containing silver-rich VMS mineralization was identified by the Company’s 2011 drill program.

Geology

The geology underlying the Dolly Varden property consists of volcano-sedimentary rocks belonging mostly to the lower and middle Jurassic Hazelton Group. These include intermediate volcanic and volcaniclastic rocks of the Betty Creek Formation and bimodal volcanic and sedimentary rocks of the Salmon River Formation.

The principal silver-base metal deposits of the Kitsault River valley have been interpreted as vein mineralization by early workers. Devlin (1986) reinterpreted the main deposits to be volcanic exhalative in origin. Deposits of this type are formed as sub-aqueous hot-spring type deposits on the seafloor, as products of hydrothermal solutions that have vented from sub-seafloor fracture and fault systems. Furthermore, the silver deposits of the upper Kitsault valley are mapped with important geological similarities to the Eskay Creek deposit, providing an analog for exploration on the Property.


Supervised Neural Network Targeting and Classification Analysis for Mineral Exploration

Posted by on Tuesday, 29 April, 2014

Karl Kwan (Geotech LTD) presented at Canadian Exploration Geophysical Society meeting (8 April 2014) methodology and examples of using Neural Network Targeting and Classification at mineral exploration.

“Geophysical survey contractors routinely offer multi-parameter data to clients. For example, a helicopter-borne survey may acquire Time-domain electromagnetic (TDEM), magnetic gradiometer and even gamma-ray spectrometer data (i.e., VTEMplus, Geotech LTD). Exploration geophysicists can certainly take advantage some of the readily available multi-disciplinary (geology, geophysics and remote sensing) and multi-parameter (potential field, EM, gamma-ray spectrometry, and others) datasets for mineral exploration. However, the integration and interpretation of these datasets can be time-consuming and even challenging, especially for large-scale datasets covering large areas with diverse geological conditions. The Supervised Neural Network (NN) Targeting and Classification technique for mineral exploration described and demonstrated by Reford, Lipton and Ugalde, 2004, “Predictive Ore Deposit Targeting Using Neural Network Analysis” (http://www.pgw.on.ca/downloads.html), can be a useful and promising tool for the analysis of multi-disciplinary and multi-parameter data.

In this presentation, the properties or responses of the two feed-forward multilayer Neural Networks, Levenberg-Marquardt (NN with LM training) and Fast Classification (FCNN), as implemented in the current version by PGW, are studied in detail. The supervised NN simulations are performed on specially constructed synthetic data. Intended as a tutorial and the NNs treated as black boxes, the objectives of the exercise are twofold, to demonstrate the targeting as well as classification capabilities of the Neural Networks, and at the same time to show one of the known limitations and to suggest a way to get around it. The utility of the NN tool is demonstrated again with real cases from the Republic of Niger.”

Geosoft is delighted to host the online portion of the Canadian Exploration Geophysical Society meeting with keynote speaker Karl Kwan, Geotech LTD.

YouTube:  


Ground geophysics in Greenland for nickel-copper-cobalt-PGM project

Posted by on Tuesday, 29 April, 2014

North American Nickel Inc. announces that Crone Geophysics of Mississauga, Ontario have mobilized their crews to the Imiak Hill Conduit Complex (IHCC), part of the Company’s 100% owned Maniitsoq nickel-copper-cobalt-PGM project in southwest Greenland.

Geophysical Surveys Underway

The geophysical survey work now underway consists of surface time-domain PEM and gravity surveys in the Imiak Hill Conduit Complex, where significant nickel-copper-cobalt PGE mineralization has been intersected in drill holes by the company over the past two drill seasons. These intersections include:

  • Imiak Hill DDH MQ-13-028: 24.75 metres of near massive to massive sulphide grading 3.19% Ni, 1.14% Cu, 0.11% Co, including; 17.91m of 3.80% nickel, 1.42% copper, 0.13% cobalt and 0.01 g/t PGM;
  • Imiak North DDH MQ-13-029: 55.75m of disseminated to near massive and massive sulphide grading: 1.28% nickel, 0.36% copper, 0.04% cobalt, and 0.03 g/t PGM, including;9.99m of 4.65% nickel, 0.33% copper, 0.13% cobalt and 0.08 g/t PGM; and
  • Spotty Hill DDH MQ-12-005: 123.94 meters of disseminated, net-texture, to near massive and massive sulphide grading 0.81% nickel, 0.21% copper, 0.03% cobalt & 0.26 g/t platinum (Pt) + palladium (Pd) + gold (Au), including: 24.20 m @ 1.75% Ni, 0.34% Cu, 0.06% Co & 0.52 g/t Pt+Pd+Au.

Geological Team Meeting April 8-10, 2014 in Winnipeg

As preparation for the 2014 field and drill program all norite-hosted nickel sulphide mineralized drill targets were reviewed by the NAN Geological team and four invited geoscientists familiar with nickel sulphide deposits and advanced methods of interpretation of geophysical responses to nickel sulphide mineralization. The review was undertaken at a meeting convened in Winnipeg by North American Nickel with a view to expanding discovery possibilities and then confirming and prioritizing drill targets for this year’s drill program.

President Dr. Mark Fedikow P.Geo. states: “Our deepest hole to date at Imiak Hill in the IHCC intersected high-grade massive sulphide nickel-copper mineralization 185 m below surface. The new geophysical ground surveys are designed to look below that depth and define the extent and shape of our high-grade mineralized zones providing plunge, strike and dip attitudes for the mineralization. The results from these 2014 ground geophysical surveys coupled with the airborne surveys and drill results from 2012 and 2013 will assist with drill targeting at the IHCC. Our team worked last week with four seasoned and internationally experienced nickel sulphide geoscientists. The agenda included a thorough review of the IHCC and all the regional norite-hosted nickel sulphide targets identified as a priority for the 2014 season. We look forward to including them again along the path to discovery at Maniitsoq.”

The PEM Survey

The PEM system operates by placing a large loop of insulated wire on the ground through which a precisely-controlled changing current induces magnetic responses from conductors hundreds of metres deep in the ground. It can be used to detect and discriminate between a wide range of conductivities from poor (zinc), to excellent (copper and nickel). Due to its unique transmitted current waveform and its receiver’s measuring system, Crone has developed a step-response transformation of the data which extends this range of detection and discrimination into the extremely high conductance that is seen in nickel exploration. This feature has made the Crone PEM system an important part of the exploration efforts in nickel exploration camps around the world, such as the Raglan camp, Voisey’s Bay, Sudbury, Alaska, Tanzania, Western Australia, and now Greenland.

The Gravity Survey

In addition to the Pulse EM survey, Crone will carry out a gravity survey with a 2 person crew consisting of a gravity operator and a GPS operator with extensive experience in precision gravity surveys. The equipment consists of LaCoste & Romberg model G gravity meters with a reading resolution of 0.01 mGal. The differential GPS (DGPS) system is the Leica – model 1230 Dual Frequency, Dual Constellation (GPS & GLONASS) RTK, rover and Base Station with an accuracy of 1 cm + 1 ppm in separation from the base station to the rover. The crew has extensive worldwide experience and is capable of reducing the data to bouguer mGal values nightly in the field. Gravity surveys measure extremely small variations in the Earth’s gravitational field, which can be used to locate high density material such as nickel sulphide-bearing rock.


Integrated airborne geophysics and geologic data interpretation for new Eskay-Creek style deposits

Posted by on Wednesday, 9 April, 2014

Dolly Varden Silver Corporation announces that through recent geoscience modeling and ongoing interpretation, the Company has focused its primary advanced exploration target areas on three corridors within the Dolly Varden property. Work is now being done to prioritize the most prospective drill-ready targets within these corridors. The corridors and targets were chosen for their potential to best expand areas of known high-grade silver mineralization and to identify new Eskay-Creek style precious metals deposits.

 

 The three targeted corridors are the 1) Torbrit-Red Point Corridor – following known silver mineralization underneath Red Point, an Eskay-Creek style target; 2) Musketeer Corridor – which runs along the east side of the Kitsault river with numerous Ag-rich epithermal vein-type showings with strong potassic radiometric signatures; and 3) Wolf-Surprise Corridor where an Eskay-Creek style host formation containing silver-rich VMS mineralization was identified by the Company’s 2011 drill program.

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Through recent modeling and ongoing interpretation, the Company has now moved from kilometer scale targeting to meter scale targeting within these defined corridors. The Company’s technical team is working to delineate specific drill ready targets within these corridors. An aggressive 40 to 50 hole (13,500 meter drill program) is being finalized, subject to financing.
The combination of airborne MAG, VTEM, ZTEM radiometric, and geochemical data, along with geological and structural mapping, was used to define priority target zones. These helped define steep linear features, syngenetic faults, lithologic contacts related to basin formation, and key fluid controlling structures. In addition, key rock units, contact zones and alteration zones most likely to be associated with mineralization, were identified.
This compilation has demonstrated that the known deposits, showings, and related alteration zones are all located within a rift setting. The key rock units that infill the rift have also been identified, and these represent viable targets for Eskay Creek style VMS mineralization. Drilling will be conducted within corridors where mineralized occurrences and coincident alteration haloes point to extensive hydrothermal fluid flow. The key target areas for 2014 drilling include syngenetic VMS-style mineralization and associated feeder structures.

New Strongly Conductive Target on Feagan Lake Graphite Project

Posted by on Wednesday, 26 March, 2014

Metals Creek Resources Corp.  reports that the company has discovered several conductive electromagnetic targets on its recently staked, 100% owned Feagan Lake Graphite property which is located approximately 7 km due west of  Zenyatta’s hydrothermal graphite discovery.

These new electromagnetic (EM) conductive responses were flown with the VTEM plus time domain system targeting previously identified magnetic lows that resulted in the discovery of several new exploration targets exhibiting similar features to that of Zenyatta’s hydrothermal graphite discovery. One of the EM responses in particular returned a strong conductive response on all channels with an associated magnetic low.

The Feagan Lake claim block consists of 12 claim blocks totaling 175 claim units and is located immediately west and adjacent to Zenyatta’s claim block.  The Feagan Lake property to the best of management’s knowledge has never been flown for EM conductors making this a brand new discovery demonstrating the potential for the area to potentially host additional graphite mineralization.

Metals Creek’s President and CEO, Alexander Stares states, “With the discovery of several new EM anomalies within favorable stratigraphy to host possible additional graphite mineralization, it provides Metals Creek with an exciting new project strategically located adjacent to Zenyatta’s hydrothermal graphite discovery.  This new highly conductive EM target will be the focus of additional exploration work going forward.”

 


Recent investigations of geophysics abilities in aquifer mapping and resource evaluation

Posted by on Thursday, 13 March, 2014

Buried beneath the glaciated terrain, valleys filled with coarse-grained permeable sediments  potentially are great sources of fresh ground water. During the last several years Geological Survey of Canada has been investigating geophysical methods potential, particularly airborne electromagntics, for mapping and resource evaluation of buried valleys.   Spiritwood valley aquifer in southern Manitoba has been chosen for the investigations. Heliborne AeroTEM, VTEM, fixed-wing TEMPEST and MULTIPULSE, ground electrical resistivity and time-domain methods, seismic reflection and borehole data have been involved into the complex analysis. Recently collected ground TEM data for Spiritwood and the report (G.A. Oldenborger and K. Brewer, 2014) has been released: http://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/fulle.web&search1=R=293700.

One of the successful heliborne TEM examples (Legault, J.M., Prikhodko, A., Dodds, D.J., MacNae, J.C., Oldenborger, G.A., 2012. Results of recent VTEM helicopter system development testing over the Spiritwood Valley aquifer, Manitoba. Symposium on the Application of Geophysics to Environmental and Engineering Problems. Environmental and Engineering Geophysical Society, 114–130.):

VTEM-ground

 

 

 

 

 

 

 

 

 

 

 

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Another recent example of the results of a combined seismic and airborne electromagnetic (AEM) interpretation of the shallow Quaternary sedimentsand  bedrock but in British Columbia (Horn River Basin) was presented on Geoconvetion-2013  .

 

 


Recent Airborne EM Survey close to Albany project

Posted by on Wednesday, 12 March, 2014

Xmet Inc. has successfully completed a Versatile Time Domain Electromagnetic Surveying (“VTEM”) survey, comprising 437 line kilometres, over 20,000 acres of recently staked 100% owned Xmet claims on its Blackflake project.
Three electromagnetic (“EM”) bedrock targets were delineated during the latest survey, including a more detailed survey over the Prime Target discovered and announced in Xmet’s December 12th, 2013 news release. Geotech, who flew the survey and assisted in interpreting the results, have concluded that all three of the anomalies extend into the bedrock beneath overburden and limestone cover.
“A tightly spaced VTEM grid survey was flown over our Prime Target in order to obtain higher resolution over the original TDEM anomaly which was originally defined over a length of 1500 meters,” said Alexander Stewart, Chairman and CEO of Xmet Inc. He continued by saying, “VTEM technology provided much deeper penetration than the TDEM survey flown over the Prime Target in late 2013. With this latest round, the conductivity and the size of the Prime Target is confirmed. The Prime Target is defined by an electromagnetic anomaly in bedrock with an associated magnetic low. The target is geologically constrained between two major diabase dykes. Two new bedrock conductors were also discovered which have similar geophysical characteristics. We are very excited about the potential of these targets, and with our ground permits now in place we are getting closer to drilling these targets.
Xmet’s Blackflake Project comprises over 29,000 acres of 100% owned claims approximately 60km to the northwest of Hearst, Ontario and is adjacent to Zenyatta’s Hydrothermal Graphite Deposit. Xmet has now conducted three airborne electromagnetic surveys, VTEM and TDEM, which discovered multiple electromagnetic conductors making the targets highly prospective for further exploration. Xmet has developed an excellent working relationship with the Constance Lake First Nation, with whom the company signed an ongoing Exploration Agreement.


Coincident Geochemical and Geophysical Data Pinpoints Drill Targets, Greyhound, Nunavut

Posted by on Saturday, 1 March, 2014

Aura Silver Resources Inc. announces the results of a comprehensive report completed by L.E Reed Geophysical Consultant Inc. (“Reed”) which supports, from a geophysical standpoint, drill targets established geochemically by Activation Laboratories Ltd. (Actlabs) Spatiotemporal Geochemical Hydrocarbon (“SGH”) technology for the Aura Lake area as well as the Dingo prospect north-west of Aura Lake, both part of the Greyhound Project, NU.

As reported by Reed, “Correlations between the geochemistry and various geophysical data suggest support for the possible identification of gold and silver deposits at Aura Lake and a gold and copper deposit at Dingo”. This report may be accessed at the Company’s web-site (http://www.aurasilver.com/s/Home.asp) under the section Projects / Canada.

The potential sources of high-grade gold boulders (up to 28 g/t) and high-grade silver (up to 5,300 g/t) have been identified in close proximity to Aura Lake. The gold and copper targets at the Dingo prospect area north-west of Aura Lake are surface showings. New interpretation of geophysical data and SGH has refined the drill targets. This geophysical analysis has identified multiple structures/contacts with the use of three-dimensional inversion imagery of airborne VTEM EM and magnetic responses and ground Induced Polarization and Resistivity data. These structures/contacts at Aura Lake may have provided a pathway for fluids carrying mineralization and are interpreted to support the drill targets originally defined by geochemical analysis.

Robert Boaz CEO and President of Aura Silver states that, “The detailed geophysics analysis undertaken by Reed gives us further comfort that we are zeroing in on the source of high-grade surface gold, silver and copper mineralization. Despite the difficult market for all junior exploration companies we continue to enhance the value of our properties.”

During the fall of 2006, an airborne MEGATEM® geophysical survey was flown on the initial property by Fugro Airborne Surveys Corp. In 2007, further prospecting of MEGATEM anomalies took place. Samples collected in 2007 contained up to 2.4% zinc (Zn), 1.02% copper (Cu), 8.1% lead (Pb), 10g/t gold (Au) and 51 g/t silver (Ag) highlighting the potential for discovery of VMS (volcanogenic massive sulphide) ores.

During 2008, Fugro completed the flying of a GEOTEM® survey over the new Greyhound claim group. Results from this survey were utilized in an on-the-ground field program to complete geological mapping and sampling. Samples prospected during 2008 contained up to 4.1% Cu, 13.4% Zn, 8% Pb, 2,700 g/t Ag and 28g/t Au and to the northeast of Aura Lake a series of boulders contained up to 18.5% Zn and 9.2% Cu.

In late 2009, a high precision VTEM® helicopter borne electro-magnetic survey was completed.


The renewed Interest in Pecors Magnetic Anomaly-Serpent River Property Near Elliot Lake, Ontario

Posted by on Friday, 21 February, 2014

International Montoro Resources Inc. – The Serpent River Property, Elliot Lake, Ontario claims consist of 10 mining claims (115 units) covering approximately 1,840 hectares located in Gaiashk & Joubin Townships. Recent renewed interest has been shown in the 3 upper northwest claims known as the Pecors Anomaly. Click following for maps/regional geophysical overview http://ow.ly/tNTbz.

Montoro congratulates Kelly Strong, V.P. of Ontario and UK Operations -Vale, in the recent startup of the Totten Mine (Totten lies 40 km to the west of Sudbury and approx. 50 km from Pecors). This is Vale’s sixth operating mine in the Sudbury Basin. A polymetallic orebody with good nickel and copper grades as well as precious metals. Click following for the complete story: http://ow.ly/tLq2T. (See page 1 & 19-34 re the Totten Mine and page 15 re the KGHM Victoria Mine Projects)

The Uranium and Rare Earths discovered in the southwest portion at Serpent River may prove to be a sideshow to another deposit type. In a 2009 summary of the Ontario Geological Survey field work, a strong geophysical anomaly on the claims that was previously thought to be caused by an iron formation was reexamined. The new interpretation on the Pecors anomaly concludes it may be the result of contact style nickel-copper-PGE mineralization similar to that found to the east at Sudbury. Sediment sampling from Pecors Lake has shown high levels of nickel and chromium, lending further weight to this analysis. The total field magnetic anomaly strikes northwesterly and is about 15 km long and about 4 km wide.

PecorsMagAnomaly

Exploration & Development of the Pecors Anomaly:

  • Int. Montoro, Pele Mtn. & Verbina Resources completed a combined VTEM survey in January 2008. An operational report for this survey was written by the contractor Geotech Ltd. in February 2008, Project 7112.
  • 2009 Ontario Geological Survey field work completed- Open File Report 6240; Project Unit 09-004. Compilation Mapping, Pecors-Whiskey Lake Area, Southern and Superior Provinces
  • February 23, 2010 brief prepared by G. Campbell, MSc. – ‘The Pecors Magnetic Anomaly located under Huronian Cover – A Possible Cu-Ni-PGE Target at the Archean-Proterozoic Boundary, Elliot Lake Area
  • May 5, 2010; Int. Montoro commissioned a report on the southern claims group of the Serpent River Property from L.E. Reed Geophysical Consultant Inc.
  • May 20, 2011; Int. Montoro initiates a search for and locates 4 historic boreholes PW #116, 117, 121 & 122 drilled by Rio Algom in 1959 on the eastern side of Pecors Lake. Holes PW 121 & 122 drilled along the south and southwestern edge of the Pecors Anomaly, penetrated the Huronian sediments and encountered underlying basement rocks at depths of 2002 feet (610 meters) and 1477 feet (450 meters) respectively. Information from the drill holes provides some corroboration of the depths from the 3D model as reported in the July 6, 2011 report following.
  • July 6, 2011; Int. Montoro commissions a report ‘Response of the Pecors Magnetic Anomaly‘ from L.E. Reed (“Reed”) Geophysical Consultant Inc. Reed ran the anomaly through a 3 dimensional inversion program (UBC, Mag3D) to develop an understanding of the three-dimensional shape and distribution of the source body for this anomaly. Measurements through a section in the center of the anomaly show a depth of 300 to 400 meters to the top and as much as 1700 meters from surface to the bottom of the magnetic source body. It appears as a broad sill, possibly an intrusion. The maximum dimensions of the entire inversion block are estimated at 7.8 km EW x 3.45 km NS and 2.025 km from surface. Select portions of the Reed Interpretation report are posted on the updated Serpent River project page on the Company website at www.MontoroResources.com
  • February 2014; Int. Montoro is actively engaging stakeholders in the Sault St. Marie & Sudbury Mining Districts to proactively move forward the exploration of the Pecors Magnetic Anomaly.

Other:

Neighboring explorer, Pele Mountain Resources (TSX VENTURE:GEM), has provided the results of an updated economic review of its Eco Ridge Mine rare earth and uranium project in Elliot Lake, Ontario. In its news release dated September 12, 2013, Pele Mountain reports the economic review concludes that the recent increase in mineral resources extends mine life and improves project economics. While this improvement is offset by a reduction in rare earth price forecasts, the net result demonstrates that Eco Ridge economics remain positive.

Int. Montoro is also seeking interested parties in continuing the development of the Serpent River southern portion of its rare earth and uranium property adjoining Pele Mountain’s claims east of Eco Ridge.


Geophysical exploration program in Nicaragua

Posted by on Tuesday, 18 February, 2014

Caza Gold Corp. announces that the Company has initiated the 2014 exploration program at the Los Andes and Pochote properties in Nicaragua. The Company is planning a large airborne geophysical survey and a drilling program which will test 2 of the highest priority gold targets.

Plans are underway to complete a geophysical survey along a 12 kilometer long trend of continuous alteration within the Los Andes and Pochote claims, followed by a drilling program to test two gold targets not previously drill tested during the 2012 Pedregal program. The upcoming drilling will test the Quisaltepe and San Francisco gold zones. Access agreements have been obtained for the San Francisco area and drill access road construction is underway. Negotiations for access in the Quisaltepe area are being finalized. The drilling program is expected to begin, pending contractor scheduling, by April and is planned to complete approximately 10 to 15 holes each 200 to 250 meters deep. A dedicated budget of approximately CDN$1.3 million has been set aside from the proceeds of the December 2013 CDN$2.5 million financing to execute the exploration program.

The Company has contracted Aeroquest Airborne to complete the helicopter based geophysical survey which will cover approximately 36 square kilometers over the Pedregal, Quisaltepe and San Francisco gold targets acquiring versatile time domain electromagnetic (VTEM) and magnetic data along approximately 530 line kilometers at 100 meter line spacing. The survey is scheduled to begin in March pending the importation of the survey equipment and final scheduling of personnel and equipment. Geophysical survey results in conjunction with geochemical results, structural and alteration mapping will further define the drilling locations.

The VTEM and magnetic data are targeting the conductive massive sulfide horizons and the resistive silicified zones associated with large faults and possible areas of gold mineralization. The magnetic portion of the survey will provide additional information identifying the fault zones and deeper porphyry style mineralization and intrusive bodies. The survey will cover the Pedregal area, drilled in 2012, which intersected thick horizons of sulfide mineralization and strongly silicified zones with elevated but sub- economic gold concentrations (refer to Nov. 29, 2012 news release for details) and along the 10 kilometer trend to the San Francisco target at the south end of the zone.

Los Andes High Sulfidation Gold Property, Nicaragua

The Los Andes Property is located approximately 1 hour east of Managua on Highway 7 with excellent access. The property covers approximately 6,575 hectares and is strategically located within the Central Nicaragua Gold Belt between the El Limon and La Libertad Mines of B2 Gold.

The Los Andes property is a high-sulfidation style of gold mineralization.  High-sulfidation gold systems host some of the largest gold deposits in the world with examples such as Yanacocha and Pierina in Peru.  Favorable alteration and mineralization has been traced along the regional northeast trending Los Andes structure for at least 11 km on the Los Andes property.  The extensive alteration system is exposed on the surface and consists of very strong silicification associated with zoned alteration from higher temperature advanced argillic zones surrounded by successively lower temperature argillic, and propyllitic alteration.  The alteration is associated with anomalous values of gold, silver, and highly anomalous levels of indicator metals such as bismuth, tellurium, selenium, arsenic, antimony, and mercury.


Airborne EM before the discovery of wide spread gold-silver-zinc-copper mineralization

Posted by on Tuesday, 18 February, 2014

Bayfield Ventures Corp. announces the completion of a National Instrument (NI) 43-101 Technical Report on the Company’s 100% owned mineral rights “B” Block gold-silver property, Rainy River district, north-western Ontario.

 

 

 

 

 

 

 

 

 

Drilling on the “B” Block property has resulted in the discovery of wide spread gold-silver-zinc-copper mineralization. No mineral resource calculations have been done on the property. Drilling to date has been relatively wide spaced and shallow. All known mineralized intercepts lie within 400 metres of surface. Less than 5% of the drilling on the property has been done below the 400 metre below surface level.

The property is positioned in the eastern portion of the developing Rainy River district. The south edge of the property is located approximately 350 metres north of the near surface position of the Intrepid shoot, located on ground controlled by New Gold. The Intrepid shoot is a SW plunging, robust zone of gold-silver mineralization that has been jointly delineated by Bayfield Ventures and Rainy River Resources since its discovery by Bayfield in December 2011.

Mineralization on the “B” Block is contained within a package of NNE striking, vertically dipping, strongly foliated, sheared and locally folded dacite porphyry wall rocks. Pervasive sericite-silica +/- biotite alteration is developed within the dacite package. Sericite is dominant in the southern half of the property while biotite and silica are well developed in the northern portion.

The interlayered dacite porphyry, argillite and mafic volcanic lithology of the known rock package at the “B” Block are very similar to that found by Bayfield at its nearby Burns Block property. Additionally, discovered gold-silver-base metal mineralization at the “B” Block is hosted within highly foliated dacite intrusive and or volcanic rocks, again, a setting very similar to that at the Burns Block and at other well mineralized zones along the developing district-scale trend.

The drilling of a series of NW trending angle holes across the SW flank of the strong VTEM anomaly in the northern portion of the “B” Block property is also recommended. Drilling in the heart of the anomaly completed in 2013 showed a rock sequence nearly identical that which overlies the Intrepid Shoot in the eastern portion of Bayfield’s Burns Block project.

The survey was flown in two distinct blocks, an eastern block covering the Burns and “B” Block exploration areas and a western block covering the large “C” Block exploration area. Interpretation of the preliminary data is complete and the following drill targets have been identified:

• A strong, discrete conductor in the east-central portion of the Burns Block has been identified and will be drill tested. No previous drilling has been done in this portion of the property. The anomaly is located in the same area as the multi gram surface samples reported above.

• A strong, discrete conductor in the northeast portion of the “B” Block has been identified and will be drill tested. No previous drilling has been done in this portion of the “B” Block property.

• The cesium magnetic data from the “C” Block survey show clear evidence of mafic volcanic rocks in the northern portion of the property. These rocks are separated from interpreted intermediate volcanic rocks by a sharp contact that is very likely a fault. The interpreted fault contact and the area of interpreted intermediate volcanic (dacite or equivalent) rocks present top quality drill targets at the “C” Block. Drill testing of this area is planned for the first quarter.


Multiple conductive anomalies within the Patterson Uranium Prospect

Posted by on Friday, 14 February, 2014

Makena Resources Inc. reports that the initial data (VTEM survey) has returned results that show multiple conductive anomalies within the Patterson Uranium Prospect. Two distinctive anomalous zones were encountered. The southern zone has three specific targets within the zone. The north target is a NW trending zone associated with a break in the formation in the direct vicinity of the conductive anomaly. A historical drill hole shows basement to be relatively shallow at 154 metres depth within these zones.

Karl Schimann stated, “We are encouraged by the preliminary data. We clearly have multiple conductive targets that we plan to aggressively follow up on shortly. Of particular note is the relationship of the conductive zones associated with the breaks in the magnetic pattern. These breaks are often associated with uranium mineralization. We look forward to potentially confirming these anomalies by ground EM and follow by drilling to determine if these targets have associated uranium mineralization.”

MKN’s Patterson Uranium Prospect, consists of three claim blocks totaling 6,687 hectares (16,524 acres), which are all located in the Athabasca Basin. The west block directly borders the recent discovery on the Patterson Lake South Property by Alpha Minerals Inc. and Fission Energy Corp. The other two blocks are in the direct vicinity of the discovery.


Exploration drilling for gold initiated by airborne geophysics results in Ghana

Posted by on Friday, 14 February, 2014

Asante Gold Corporation  announces final results and interpretation of the exploration drilling completed to date on the Fahiakoba gold concession in Ghana.

Drill holes were spotted to test sections of airborne geophysical (MAG/VTEM) and ground auger soil geochemical anomalies. Initial drill holes were spaced from 400m to over 1km apart and later tightened to 100m step-outs where gold mineralization was noted. A total of 30 drill holes were completed in two phases, for 4985 m. A collar map is available at:http://www.goknet.net/Asante/FAHcollarsNRJan20.pdf.

Geotech conductivity depth inversion

With the exception of four significant gold intersections (to 0.50 m @ 295 g/t Au), initial sampling results were low. VTEM conductors correspond with favourable graphitic shear zones in meta-greywacke or regional scale graphitic meta-phyllite/argillite units. Weak gold anomalies in core from saprolite have generally accounted for the anomalous auger soil geochemical targets tested in the program.

However, wide zones of moderate to strongly quartz veined meta-greywacke, and carbonate alteration were noted in the program. These zones correspond with elevated to locally significant gold values, as noted in the table below, and are considered high priority targets for additional drilling.

Further drilling is also required along the trend to the NE of Perseus Mining Ltd’s discovery hole NSRC010 located ~1 km south of the Asante Fahiakoba concession boundary and which yielded 30m at 2.2 g/t Au, including 4m at 9.0 g/t Au (Perseus Quarterly Report, December 30, 2012 – true width unspecified).

 

Property Geology

The property is underlain by favourable Birimian meta-sediments, with more than 70% of the Fahiakoba concession covered by transported alluvial material. No modern exploration or drilling has taken place to date. Recent airborne geophysical surveys have outlined some 20 km of strong NE trending shear and fold zones, some of which have associated VTEM conductors. These type of structural targets at Perseus and elsewhere in Ghana host significant gold deposits and will be the target of our ongoing exploration efforts. Anomalous gold values have been noted in a pit with quartz stockwork in granite that is associated with one of the airborne geophysical targets. Phase 1 auger drilling to test below the alluvial cover has been completed with anomalous gold trends identified.