Posts Tagged VTEM

Airborne EM for VMS on ARMSTRONG BROOK PROJECT, NEW BRUNSWICK

Posted by AP on Friday, 31 May, 2013
The 2013 exploration program on the Armstrong Brook project commenced in early May. Highlights include the discovery of additional clusters of high-grade massive sulphide boulders in multiple locations (namely VMS Valley 4 & 5) and the completion of an airborne geophysical survey (VTEM) that identified intriguing anomalies in the vicinity of the primary boulder clusters.
The Armstrong Brook project comprises a number of high-grade polymetallic volcanogenic massive sulphide (VMS) prospects located in the Bathurst Mining Camp of northeastern New Brunswick, situated approximately 15 kilometres northwest of the Brunswick No. 12 Zn-Pb-Ag-Au deposit. Brunswick No. 12 is one of the world’s premier VMS deposits, having produced zinc, lead, silver and gold over a mine life of some 60 years.
VMS Valley 4:
The new discoveries at VMS Valley 4 occur as 2 boulder clusters located approximately 300 metres apart. Samples from the first cluster (AR13-0007-1 and 2) and the second cluster (AR13-0008-1 through 6), have returned high-grade mineralization with combined zinc+lead average assays of 13.68% and 10.33%, respectively, with impressive precious-metals as high as 459 grams per tonne silver and 1.07 grams per tonne gold. Complete assay results from the new boulder discoveries .
VMS Valley 5:
Additional prospecting has been completed in the vicinity of a recently discovered cluster of boulders located in the northwestern portion of the property. This work resulted in the discovery of 5 massive sulphide boulders in the vicinity of a discovery reported earlier in 2013, that yielded high-grade results with assays of up to 13.07% Zn, 6.07% Pb, 0.76% Cu, 251 g/t Ag and 0.66 g/t Au (see Wolfden news release dated March 20, 2013). These discoveries occur over an intermittent strike length of close to 700 metres and occur coincident to a significant geophysical anomaly that was identified in the recently completed VTEM airborne geophysical survey.
Assays remain pending for the new massive boulders from VMS Valley 5.
Preliminary results obtained from the VTEM survey indicate that the massive sulphide boulders are intimately associated with the eastern margin of a strong electromagnetic anomaly (EM conductor). This hook-shaped conductor attains a strike length of approximately 2 kilometres (see Image 1). Additionally, the cluster of massive sulphide boulders at VMS Valley 5 is centred within a broad circular-shaped magnetic high (total magnetic intensity) that has a radius of approximately 2.5 kilometres (see Image 2). Clearly, this anomaly requires detailed follow-up in the way of ground geophysical surveys prior to diamond drilling.

The 2013 exploration program on the Armstrong Brook project commenced in early May. Highlights include the discovery of additional clusters of high-grade massive sulphide boulders in multiple locations (namely VMS Valley 4 & 5) and the completion of an airborne geophysical survey (VTEM) that identified intriguing anomalies in the vicinity of the primary boulder clusters.The Armstrong Brook project comprises a number of high-grade polymetallic volcanogenic massive sulphide (VMS) prospects located in the Bathurst Mining Camp of northeastern New Brunswick, situated approximately 15 kilometres northwest of the Brunswick No. 12 Zn-Pb-Ag-Au deposit. Brunswick No. 12 is one of the world’s premier VMS deposits, having produced zinc, lead, silver and gold over a mine life of some 60 years.


Airborne Magnetic and Electro Magnetic Survey at Patterson Lake for uranium

Posted by AP on Wednesday, 29 May, 2013

Aldrin Resource Corp. announces the immediate commencement of a high-resolution airborne magnetic and electromagnetic geophysical survey covering the Triple M Property (“Property”). The survey is being flown by Aeroquest Airborne, a division of Geotech, using their advanced helicopter-borne, time domain electromagnetic VTEM plus system and magnetic gradiometer. The survey will cover all of the Triple M Property at 200 m line spacing, and is expected to begin flying today. Flying the survey over the Property is anticipated to take 6 to 9 days.

The survey is designed to detect conductors and magnetically defined structures that may define targets for uranium mineralization. Such conductive and magnetic anomalies may extend the mineralized structures associated with Alpha Minerals Inc and Fission Uranium’s (“Alpha/Fission”) reported high-grade Patterson Lake discovery 10 km east on the adjacent property to the Triple M Property. Alpha/Fission reportedly used a similar Aeroquest VTEM airborne survey to define conductors associated with their high-grade intersections on their Patterson Lake property, based on information contained in Alpha’s recently released independent technical report available on SEDAR (dated April 23, 2013). Some maps in that technical report suggest that VTEM conductors extend to the contiguous edge of the Triple M Property with the Patterson Lake discovery property. Geology is indicating that the conductors and structures may extend onto the Triple M Property from the Patterson Lake discovery and this will be confirmed by the airborne survey.

Aldrin’s Triple M Uranium Property is located in the Patterson Lake Area of Saskatchewan. The property consists of 6 claim blocks totalling 12,001 ha and is bordering the Fission Uranium Corp./Alpha Minerals Inc. discovery at Patterson Lake 9 km south to 11 km west of their recent discovery.

The Property is located just outside the southwestern margin of the Athabasca Basin, which currently accounts for 20% of the world’s total uranium production. The Athabasca Basin’s uranium production comes primarily from Cameco’s high-grade (16.5% U3O8 after allowance for dilution) McArthur River Uranium Mine, which alone produced 14% of the world’s supply in 2011. Other major current and past-producers from the Athabasca Basin include the Cluff Lake, Key Lake, Maclean Lake and Rabbit Lake Uranium Mines, as well as the soon-to-open Cigar Lake Project (Fig. 1). The Triple M Property extends from 400 m to 20 km south of the Athabasca Basin margin. The Property is adjacent to Fission Energy Corp’s and Alpha Minerals Inc.’s Patterson Lake South JV property (“Fission” or “Fission / Alpha JV”), where Fission recently announced discovery of high-grade uranium mineralization (Fission NR dated December 5, 2012) in basement 5 km southwest of the Athabasca Basin margin . The Triple M Property’s location adjacent to the Athabasca basin margin, and near the recent high-grade uranium discovery at Patterson Lake has motivated Aldrin to commence uranium exploration.


The results of the EM/Magnetic airborne survey over the Borden Lake Extension

Posted by AP on Wednesday, 29 May, 2013

Nikos Explorations Ltd. announces the results of the high-resolution VTEM (Versatile Time-Domain Electromagnetic System) and magnetic airborne survey recently completed over the Borden Lake Extension by Geotech Ltd. A total of 391 line kilometers were flown to cover the Property. The VTEM and magnetic surveys were completed in order to identify electromagnetic and magnetic anomalies that may be associated with gold mineralization and to help in the geological interpretation of this underexplored area.

Results of the surveys indicate electromagnetic and/or magnetic anomalies in four areas of interest (see map at http://nikosexplorations.com/projects/borden_lake/) described below in order of priority for follow up:

1. Several magnetic lineaments, one of which is interpreted to be a fault, intersect near the boundaries of claims 4260529 and 4260530. Such lineaments can reflect structures that are known to be important in the transport of gold-rich fluids. A north-east south-west lineament, apparent on a shaded relief map of the region, also crosses the Nikos claims in this area giving further reason for follow up.

2. Cross cutting NNW-SSE and NE-SW trending positive magnetic anomalies in claim 4259808 may represent major structures. There are also coincident weak electromagnetic anomalies that could indicate the presence of sulphide.

3. Similar cross-cutting magnetic anomalies and electromagnetic anomalies seven to eight hundred metres east of 2, but not as strong.

4. This area in the east of the property is characterised by a small positive magnetic anomaly with a coincident electromagnetic anomaly.

Nikos is planning a follow up program of mapping, sampling and prospecting to investigate the cause of the anomalies.

The Borden Lake Extension Project is located near the town of Chapleau, Ontario in an area of good infrastructure including road, rail and power. It covers an area of 1,598 hectares immediately east of Probe Mine’s Borden Lake gold property where recent exploration has defined pit constrained indicated resources of 3,686,000 ounces of gold (112.8 M tonnes grading 1.02g/t gold) and inferred resources of 625,000 ounces of gold (18.04 M tonnes grading 1.08g/t gold) at a 0.5g/t cutoff grade. This is the first discovery of significant gold in the Kapuskasing Structural Zone.

The Borden Lake Extension property covers Archean aged metamorphic rocks in an underexplored portion of the Kapuskasing Structural Zone.

Nikos is planning an airbourne geophysical survey using VTEM (versatile time domain electromagnetics) and magnetics to explore for Borden Lake type gold mineralization. Gold at Borden Lake is associated with a continuous zone of disseminated sulphide (pyrite and pyrrhotite) mineralization that gives rise to electromagnetic anomalies. The airbourne survey is expected to be completed during the first quarter of 2013.


Airborne Geophysical Survey Along Trend Of The Alpha/Fission Patterson Lake Discovery

Posted by AP on Tuesday, 28 May, 2013

Forum Uranium Corp. announces the commencement of an electromagnetic and magnetic survey of its 100% owned Clearwater Project. Forum’s claims, staked immediately adjacent to the southwest of the Alpha Minerals/Fission Uranium claim boundary is interpreted to be on strike with the fertile conductive trend that hosts the high-grade uranium discovery on the Patterson Lake South project. Forum’s property lies only four kilometres southwest of the high grade boulder train on the Alpha/Fission property.

Figure shows historical electromagnetic trends, a magnetic map and lake sediment geochemical surveys in the Patterson Lake South area. The electromagnetic (EM) surveys stopped at Forum’s claim boundary, however EM conductors from these historic surveys trend in the direction of Forum’s ground. Of particular note is that the highest lake sediment value in the area lies on Forum’s southwest claim with a value of 8.3 ppm U. Most values are between 1 to 3 ppm U and the lake sediment sample taken down-ice from the Patterson lake boulder field was 3.2 ppm U.

An Aeroquest Airborne helicopter-borne time domain electromagnetic survey with Bfield-VTEM Plus and magnetic gradiometer system will be flown on 200 metre line spacings for a total of 647 line kilometres over Forum’s 99 square kilometre property. The VTEM Plus system has been chosen for its depth penetration and vertical/spatial resolution of graphitic conductors that are prospective hosts for unconformity-style uranium deposits.

This is the first phase of this year’s summer exploration program. Plans are to conduct an airborne radiometric survey and a detailed prospecting survey to search for any boulder fields similar to that found on the Alpha/Fission ground.


Airborne EM and down-hole gravity for gold intersection in NW Ontario

Posted by AP on Thursday, 16 May, 2013

Northern Shield Resources Inc. announces the intersection of significant visible gold during the first phase of a 3,000 metre drilling program being carried out this spring at the Wabassi VMS (volcanogenic massive sulphide) project located in northwestern Ontario. The Wabassi project is being explored under a 49/51 JV with Discovery Harbor Resource Corp.

In the process of drill testing Anomaly “N” (a high priority VTEM conductor defining a massive sulfide target), a quartz-carbonate alteration zone with a veinlet of visible gold was intersected from 98.8 to 98.95 metres in drill-hole 13WA-33. The 0.15 metre sample assayed 2,530 g/t Au (73.8 ounces/ton). A second interval assayed 5.86 g/t Au over 1.1 metre from 100 to 101.1 meters. The auriferous zone appears to be related to an intermediate intrusive dike or sill and occurs at the contact of this intrusive and the altered mafic volcanic rocks. Photos of the core containing the gold veinlet can be seen on Northern Shield’s website at www.northern-shield.com.

This intersection of gold is the fourth gold discovery that has been made to date within the Wabassi-Tempest properties and the second to contain visible gold. Globally, gold mineralization is present in a majority of VMS districts.

In total, four drill holes were completed in the first phase of the program, which was aiming at testing three VTEM targets (K, M and N). No other significant mineralization was identified nor was anything intersected to explain the VTEM anomalies.

A down-hole gravity survey (Gravilog) was also recently completed by Abitibi Geophysics at Anomaly E. The results from the survey show dense masses in the subsurface that are coincident with and ‘off hole’ from drill intercepts where strong zinc-copper-silver mineralization is present. The upcoming drill program will include the testing of these newly defined targets at Anomaly E, including tests to determine whether the modeled shallow mineralization is present as well as the mineralization modeled at depth. Sketches representing 3D models of the gravity survey results are posted on Northern Shield’s website.

The second phase of drilling is planned to resume immediately after the spring breakup period, likely at the end of May, 2013. Much of the second phase will be focused on continuing to define the copper-zinc-silver-gold mineralization at “E.” This includes several gravity anomalies, which support previous geophysical interpretation that the mineralization extends at depth. Additional drilling will also be planned to test this exciting new gold discovery at “N”.

The Wabassi project is being overseen by Christine Vaillancourt, Chief Geologist for Northern Shield and a Qualified Person under National Instrument 43-101. The drilling was conducted by Vital Drilling Ltd. of Sudbury, Ontario. Samples were analyzed by ALS Minerals laboratories in Vancouver, BC for Au by fire assay with ICP-AES finish and base metals by four acid digestion and ICP-AES. Ore grade gold was analyzed with ALS’s Au-GRA21 method, a fire assay with gravimetric finish. Down-hole gravity was completed by Abitibi Geophysics Ltd. of Val d’Or, Quebec.

Northern Shield is an innovative, results-driven Canadian company focused on Platinum Group Element (PGE) and nickel-copper-(PGE) exploration in Canada and Greenland and copper-zinc-silver exploration on its Wabassi and Storm properties in northern Ontario. Its mission is to create a successful mineral exploration company through technical excellence and efficient management, where success is measured by the identification and development of high-quality mineral exploration projects, which may ultimately be optioned, sold or developed for maximum return on investment.


Graphite discoveries in Northeastern Ontario

Posted by AP on Thursday, 16 May, 2013

Zenyatta Ventures Ltd. announced a drilling update on the 100% owned Albany (Hydrothermal) Graphite Deposit, located in northeastern Ontario, Canada.

The first drill hole (Z13-4F10) intersected 363 metres (‘m’) of graphite mineralization from 47.0 m to 410.0 m.  This represents the widest zone of graphite material intersected to date on the Albany deposit.  The hole, which was drilled at a 180 azimuth and -65 dip, was designed to test between previously drilled holes 5 and 9.  From surface to 41.0 m hole 10 intersected overburden and from 41.0m to 47.0 m intersected Paleozoic limestone.  Graphitic overprinting was encountered from 47.0 m to 87.0 m, while the strongest graphitic mineralization was intersected from 87.0 m to 410.0 m. Drilling shows different types of graphite mineralization consisting of clasts of graphite vein material, disseminated graphite matrix and discrete graphite veins / veinlets as part of a large breccia pipe.  Geometry and true width of the graphite breccia pipe is difficult to determine at this point and will require much more drilling.

The Company will continue to define the size and grade of this rare, ‘vein-type’ or hydrothermal-style graphite deposit.  The goal of the current program will be to expand on a 2012 drilling campaign that intersected a large mineralized zone of graphitic breccia and veining from widely spaced drill holes.  This previous nine (9) hole drill program succeeded in establishing widespread graphite mineralization laterally for several hundred metres and to a vertical depth of 400m, where it remains open. The current drilling will consist of a minimum of 10,000m and will further test the extent of the Geotech VTEM airborne conductor. The program will require 40 holes and is expected to continue until August, after which a NI 43-101 resource estimate will be calculated. The Company anticipates a steady flow of information from drilling activities and continued metallurgical work from this fully funded $4 million exploration program for the balance of 2013.

14 May 2013

Zenyatta Ventures Ltd. announced the following significant assay results from the first hole (#10) of the current campaign on the 100% owned Albany (Hydrothermal) Graphite Deposit, located in northeastern Ontario, Canada.   Drill hole 10 intersected 360.8 metres (‘m’) of graphite mineralization from 49.0 m to 409.8 m yielding an average grade of 5.1% Carbon (‘C’).  This represents the widest zone of graphite material intersected to date on the Albany deposit.  The hole, which was drilled at a 180° azimuth and -65° dip, was designed to test between previously drilled holes 4, 5 and 9.  Five more holes have since been completed, all of which yielded broad intervals of graphite mineralization from visual observations of drill core as described below.  Holes 11 through 15 have been designed to start outside the limit of the indicated anomaly and were angled to help define and confirm the overall geometry of the pipe-like body.  Drill hole data from all 15 holes is shown in a table at the end of this press release.

• Drill hole 11 intersected 202.0 m of graphite mineralization from 393.0 m to 595.0 m.

• Drill hole 12 intersected 195.0 m of graphite mineralization from   90.0 m to 285.0 m.

• Drill hole 13 intersected 219.0 m of graphite mineralization from   96.0 m to 315.0 m.

• Drill hole 14 intersected 286.9 m of graphite mineralization from 108.8 m to 395.7 m and a second zone of 127.3 m of graphite mineralization from 431.3 m to 558.0 m

• Drill hole 15 intersected 301.9 m of graphite mineralization from   63.3 m to 365.2 m.   (All lengths reported are drill intersected core lengths and do not represent true widths)

Aubrey Eveleigh, President and CEO stated “These latest results confirm the exceptional size potential of the Albany graphite deposit and along with the previously announced ultra-high purity (>99.99% C) values, underpins Zenyatta’s extraordinary graphite project. Hole 10 represents the best grade drill intersection obtained to date and the more recent drill holes are confirming both the internal continuity and the extent of the deposit.”   Graphite mineralization appears to consist of graphitic breccia pipes which are typically surrounded by a zone of graphite overprinted syenite. Carbon analyses for drill holes 11 through 15 will be released once received.  Drill hole 16 has commenced, and the current campaign will continue until sufficient drill holes have been completed, following which a NI 43-101 compliant resource estimate will be prepared.  A plan map, section and drill hole table will be placed on the website today.

The Company has also completed a ground geophysical survey to better define the geometry of the Albany graphite breccia pipes and expects the full data to be released in the next few days once a final report has been completed by Crone Geophysics and Exploration Ltd. The survey has defined two adjacent, strongly conductive, geophysical (EM) anomalies that are roughly circular in shape.  Holes 10 through 15 were drilled on the eastern most anomaly (Eastern breccia pipe), and are suggesting an oval shaped body approximately 200 metres in a NW-SE long axis by approximately 125 metres NE-SW.  Additionally, hole 11 intersected mineralization at approximately 500 metres vertical depth.  Drill intercepts appear to be correlating well with the shape of the ground geophysical anomaly with additional drilling required to confirm this model. The western anomaly (Western breccia pipe), which appears to be larger, will also be fully tested during the current drill campaign.


Drilling in the Snow Lake greenstone belt

Posted by AP on Thursday, 2 May, 2013

MS Ventures Inc. updates shareholders on the progress of its winter drill programs.

The Company has completed drill testing its 100%-owned base metal massive sulphide-type targets in the Snow Lake greenstone belt of Manitoba and several targets in the North Range of the Sudbury Basin, Ontario. All targets in Manitoba have been selected for drill testing subsequent to the integration of airborne VTEM or ground EM-magnetic geophysical surveys and Mobile Metal Ions (“MMI”) soil geochemistry coupled with a review of historic exploration databases. The Company completed 13 holes with two holes abandoned due to low water supply for a total of 3,259.9 metres. In Sudbury, the Company completed three skid mounted drill holes following up TDEM, VLF-EM and MMI anomalies on the Terra Incognita project for a total of 440.6 metres.

Drill testing of Manitoba targets began on the Reed East project and finished on our Copper project. All targets were confirmed as uneconomic iron sulphide mineralization, generally associated with graphitic argillite within basaltic host rocks.

Neil Richardson, COO states: “The cold winter and spring have been exceptionally good for skid mounted drilling with frozen ground providing good access to many of our planned targets. The cold weather created some problems with small ponds frozen solid, providing an inadequate water source for drilling of two targets. We continue to see excellent correspondence between our geophysical targets and the drill results in explaining the anomalies.”

The drilling for this season was completed on April 17, 2013. The final assay results for the last few holes are outstanding at the time of writing.


Ni-Cu sulphide exploration target in a recent airborne EM in Australia

Posted by AP on Thursday, 11 April, 2013

Cassini Resources (ASX: CZI) has defined a large scale high priority nickel-copper sulphide exploration target in a recent versatile time domain electromagnetic (VTEM) geophysical survey over its West Musgrave Project in Western Australia. Source..


The company believes the West Musgrave Project has the potential to host another large nickel-copper sulphide deposit such as BHP Billiton’s nearby 1.66 million tonne copper equivalent Nebo‐Babel deposit.

The target at West Musgrave is defined by a strong electromagnetic anomaly occurring over a strike length of about 600 metres.

The electromagnetic anomaly coincides with a dipolar total magnetic intensity anomaly.

Magmatic nickel sulphide deposits are usually highly conductive, and are often hosted by mafic and ultramafic rocks containing the magnetic iron oxide mineral, magnetite.

Cassini has begun planning and permitting for an on‐ground electromagnetic survey which will assist in defining higher order conductors and help to prioritise subsequent drill program targets.

The Musgrave is a poorly explored province currently experiencing aggressive exploration expenditure following the discovery of BHPB’s Nebo and Babel nickel-copper-PGE sulphide deposits. Beadell Resources’ “Handpump” project has seen the first intersections of economic gold mineralisation in the Musgrave.

The tenements are prospective for nickel, copper, Platinum Group Element’s (PGE), gold and iron.

Many of the gravity and magnetic anomalies identified by majors BHP Billiton and Anglo Australian are located on the project. None of these have been tested by drilling. Cassini looks forward to commencing exploration or partnership opportunities on successful grant of the tenements.


The new discovery on Sugar Zone Property (Ontario)

Posted by AP on Monday, 1 April, 2013

HARTE GOLD CORP. provides an update of current operations at the Sugar Zone Property.

VTEM Target Drilling

Harte Gold has completed a four hole diamond drill program on the Ni-Cu VTEM anomaly located at the north end of the Dayhossarah lake on Harte Gold’s Sugar Zone Property.

The drilling discovered a broad zone of semi massive to massive sulphides in Komatiites with intersections up to 160 metres in thickness with primarily pyrite and pyrrhotite.

Assays of the drill core contained minor amounts of nickel, copper, platinum and palladium. Some higher grade intersections of magnesium were discovered running up to 11% Mg and were associated with biotite schists. No further work will be done on this target at this time.

“The VTEM Survey clearly outlined an area of massive sulphides that was proven with the drilling,” said Stephen G. Roman, Harte Gold’s President & CEO. “Now we need to test the other VTEM targets we have generated with our 2012 survey, to potentially discover new areas of economic mineralization on the Sugar Zone Property.”

Sugar Zone Deposit Bulk Sample Update

Harte Gold is pleased to announce the Ministry of Northern Development and Mines has accepted and filed its Closure Plan for the 70,000 tonne bulk sample. Harte Gold is proceeding with other permitting work associated with site preparation and underground development and looks forward to moving forward with this project.

Harte Gold is currently conducting a 1,500 metre seven (7) diamond drill hole program to establish 35 metre pierce points and confirm the grade in the bulk sample area. Assay results will follow.

http://www.hartegold.com/wpress/wp-content/uploads/2013/03/2013-02-27-March-2013-Final.pdf


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

Posted by AP 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..


USGS: Iowa Meteorite Crater Confirmed

Posted by AP on Wednesday, 13 March, 2013

Recent airborne geophysical surveys near Decorah, Iowa are providing an unprecedented look at a 470- million-year-old meteorite crater concealed beneath bedrock and sediments.

The aerial surveys, a collaboration of the U.S. Geological Survey with the Iowa and Minnesota Geological Surveys, were conducted in the last 60 days to map geologic structures and assess the mineral and water resources of the region.

“Capturing images of an ancient meteorite impact was a huge bonus,” said Dr. Paul Bedrosian, a USGS geophysicist in Denver who is leading the effort to model the recently acquired geophysical data. “These findings highlight the range of applications that these geophysical methods can address.”

In 2008-09, geologists from the Iowa Department of Natural Resources’ (Iowa DNR) Iowa Geological and Water Survey hypothesized what has become known as the Decorah Impact Structure. The scientists examined water well drill-cuttings and recognized a unique shale unit preserved only beneath and near the city of Decorah. The extent of the shale, which was deposited after the impact by an ancient seaway, defines a “nice circular basin” of 5.5 km width, according to Robert McKay, a geologist at the Iowa Geological Survey.

Bevan French, a scientist the Smithsonian’s National Museum of Natural History, subsequently identified shocked quartz – considered strong evidence of an extra-terrestrial impact – in samples of sub-shale breccia from within the crater.

“The recognition of this buried geological structure was possible because of the collaboration of a local geologist, water well drillers, the USGS STATEMAP program, and the support of the Iowa DNR concerning research on fundamental aspects of Iowa geology,” said McKay.

The recent geophysical surveys include an airborne electromagnetic system, which is sensitive to how well rocks conduct electricity, and airborne gravity gradiometry, which measures subtle changes in rock density. The surveys both confirm the earlier work and provide a new view of the Decorah Impact Structure. Models of the electromagnetic data show a crater filled with electrically conductive shale and the underlying breccia, which is rock composed of broken fragments of rock cemented together by a fine-grained matrix.

“The shale is an ideal target and provides the electrical contrast that allows us to clearly image the geometry and internal structure of the crater,” Bedrosian said.

More analysis of the data will provide additional detail. These data show the impact as a nearly circular region distinct from the surrounding area to a depth of several hundred meters.

“These data, when coupled with physical property measurements on drill core samples, will form the basis for modeling efforts to constrain the impact geometry and energy of the meteorite,” said Dr. Andy Kass, a USGS geophysicist working on the effort.

The Iowa and Minnesota airborne geophysical surveys are targeting an igneous intrusion, known as the Northeast Iowa Igneous Intrusive complex, that may be similar to the Duluth layered igneous complex exposed in the Lake Superior region of northern Minnesota. Known copper, nickel, and platinum group metal resources were deposited during the formation of the Duluth complex. Both of these complexes are associated with a large structural feature known as the Midcontinent Rift, which is exposed in the Lake Superior Region but is covered by younger rocks as it extends to the south through Iowa, Nebraska, Kansas, and Missouri.

This geophysical survey is part of a larger USGS effort to evaluate the concealed mineral resource potential of the greater Midcontinent Rift region that formed about 1.1 billion years ago.

U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192
Heidi  Koontz 1-click interview

Robert McKay


EMIT Maxwell Configuration File for VTEM system

Posted by AP on Sunday, 10 March, 2013

PDF file


DRILL TEST Airborne EM TARGETS IN THE ALLEN LAKE AREA

Posted by AP on Friday, 1 March, 2013

Canadian Platinum Corp. announces the commencement of a drilling program to drill test two VTEM anomalies associated with the Allen Lake Magnetic anomaly in the Peter Lake Project for the presence of Cu/Ni/PGE mineralization.  The program will test the anomaly with three drill holes totaling 1000 m.

In late 2011 CPC carried out a 1513.4 km VTEM survey targeting the Swan Lake, Allen Lake and Rutherford Lake areas of the Peter Lake Property (see CPC News Release July 31, 2012). The strongest EM/Magnetic anomaly in the survey is the Allen Lake anomaly. The anomaly consist of two electro-magnetic (EM) anomalies with strike lengths of approximately 1000 m and 600 m that appear to be bounding a strong magnetic anomaly which may represent a buried mafic intrusive body, similar to that which hosts the Swan Lake mineralization. The EM conductors and magnetic anomaly have a modeled depth of approximately 250 to 300 m. A TDEM Survey confirms the presence of complex, early time conductors. Geological mapping in the area of the magnetic anomaly confirms the presence of gabbro. Samples from a prospecting program in the area magnetic anomaly assayed 0.188% Cu, 0.055% Ni, 41 ppb Pt, 49 ppb Pd. Samples from the area of the magnetic anomaly taken by previous workers and reported in assessment files give values of 905 ppm Cu and 100 ppb Pt.

President and CEO of CPC, states “Given the understanding gained by our work in identifying and delineated the Cu/Ni/PGE mineralization at the Swan Lake deposit, we consider the Allen Lake target a very strong target for the presence of a Cu/Ni/PGE deposit”

The Peter Lake Project is located in Northern Saskatchewan. The southwestern boundary of the property is approximately 240 KM north-north east of La Ronge, Saskatchewan and approximately 110 km south of Points Landing. The project is now comprised of 31 mining claims totalling 141,863 hectares of land encompassing the Swan Lake complex. This Complex represents the largest ultra mafic complex in North America. To date, Canadian Platinum has drilled 43 holes for a total of 13,316 meters. The GSC has picked the Swan Lake ultra mafic complex as the number one exploration target for platinum group metal in Canada.

During 2011, the Corporation focused on delineating the mineralization and its geological controls, and followed up on the geochemical anomalies identified in the 2010 program. Work on the claims involved detailed geological mapping of the Swan Lake grid in order to identify stratigraphy internal to the gabbro/pyroxenite. To identify structures, the area was surveyed with these techniques to define drill targets and target geometry. Examination of the surface geology and drill core was completed and drill testing of the anomalies outlined was completed.

The best assay results to date is 81.5 meters of 0.632g/t Au+Pt+Pd and 0.4803% Cu and in addition 0.276% Ni. The Swan Lake mineralization represents a polymetallic metallurgy of copper, nickel, cobalt, gold, platinum, palladium, rhodium and iridium.


New Airborne and Ground Geophysical Surveys on Detour Gold Trend Properties

Posted by AP on Friday, 1 March, 2013

Adventure Gold Inc. announces the commencement of a significant exploration program on its 100%-owned Detour Quebec project along the Detour Gold Trend (“DGT”) in Abitibi, Quebec. The exploration program will consist of airborne and ground geophysical surveys on the best targets identified last year following a comprehensive geological modeling of the DGT. A helicopter-borne electromagnetic VTEM-type survey (VTEM) totalling 575 km, 400 km of detailed ground magnetic surveys and 30 km of Induced Polarization (IP) surveys are currently underway or will start soon.

Since last year, the Company has been actively exploring its Detour Quebec properties by completing 103 kilometres of IP surveys, 365 kilometres of detailed ground magnetic surveys, and 912 kilometres of high-definition helicopter-borne magnetic surveys. This work has highlighted new and very promising drilling targets by identifying IP anomalies close to strong gold anomalies in till, along strike from positive gold results intersected by historical drill holes. Geological modeling outlined nine possible distinct bedrock source areas along the Sunday Lake, Massicotte, and Lower Detour/Grasset gold deformation zones on our properties. Three possible bedrock source areas were covered by geophysical surveys (IP and Mag) in 2012 and nine new ground geophysical surveys will be completed over the other areas this year (see Figure 1 and press release dated November 14, 2012).

On the two northernmost claim blocks (Manthet and Martigny) respectively located 15 and 25 kilometres from the Detour Lake mine, adjacent and close to the Ontario border, two VTEM surveys totalling 575 km will be completed. Historically, very little exploration work has been completed on these claims and limited drilling in one area outlined VMS-style gold, zinc and copper mineralization. This geological environment shows some similarities with the Martiniere project located further east, where Balmoral Resources Ltd is actively exploring the Martiniere West, Bug Lake, and Martiniere East zones. In this emerging gold play, very high-grade drill intersections were recently reported, namely 273.0 g/t Au over 3.9 metres and 11.7 g/t Au over 8.9 metres (see Balmoral Resources Ltd press releases dated August 16, 2012 and January 28, 2013). The VTEM-type survey is known for its exceptional depth penetration and provides a more accurate definition of electromagnetic anomalies than conventional systems. At the Detour Lake mine, the original discovery of the main zone is directly credited to the presence of an airborne electromagnetic anomaly detected during an Input-type survey in 1974. On the Manthet and Martigny claim blocks, new east-west and northwest trends outlined last year and interpreted as subsidiary faults of the Sunday Lake deformation zone will be covered by the VTEM survey.

“Following recent successes in identifying quality drilling targets, firstly by outlining the best areas using our comprehensive geological model and secondly by performing detailed geophysical surveys, we have great expectations for the 2013 geophysical surveys, which will be mainly conducted over new claims acquired in April 2012. Once this work has been completed, we will plan a substantial drilling program scheduled to start next winter”, stated Marco Gagnon, President and CEO of Adventure Gold Inc.

The Detour Quebec project includes nine properties, 100%-owned by the Company, totalling 747 claims and covering a surface area of 40,397 hectares or 404 km2. The Detour Quebec properties are strategically located along the DGT over 80 km strike length and encompass three major proven gold structures, namely the Sunday Lake, Massicotte, and Lower Detour/Grasset deformation zones. The DGT hosts the Detour Lake gold deposit with NI 43-101 proven and probable reserves of 15.6 M ounces of gold (from global measured and indicated resources of 23.3 M ounces and inferred resources of 5.8 M ounces: see Detour Gold Corporation press release dated January 25, 2012). Adventure Gold’s Detour Quebec properties are adjacent to Detour Gold Corporation properties located on the Ontario border.

For more information on the Detour Quebec properties, please see Figure 1 and visit our website at www.adventure-gold.com:

http://www.adventure-gold.com/common/documents/Detour_Figure1_Travaux2013_26fevrier2013.pdf

Jules Riopel, P.Geo., Vice-President Exploration and Acquisitions, acting as the Company’s “Qualified Person” as defined by NI 43-101, has reviewed this press release and supervised the exploration program on the Detour Quebec properties.


High-Grade Massive Sulphide Intervals at Ntaka Hill in Tanzania

Posted by AP on Thursday, 20 December, 2012

IMX Resources Limited -

Highlights from drilling at Sleeping Giant at the Ntaka Hill Nickel Sulphide Project

  • Significant new intersections on Sleeping Giant zone, including:
    • 50m at 1.10% Ni and 0.22% Cu from 340m, including 11.45m at 2.87% Ni and 0.52% Cu from 378.55m and 1.25m at 16.30% Ni and 2.92% copper from 378.55m
    • 17m at 1.25% Ni and 0.21% Cu from 303m
    • 50m at 0.57% Ni and 0.10% Cu from 376m
    • 33.7m at 0.61% Ni and 0.12% Cu from 21.3m
  • Additional wide near surface disseminated hanging wall mineralisation intersections, including:
    • 101m at 0.40% Ni and 0.09% Cu from 24m
    • 59m at 0.49% Ni and 0.11% Cu from 169m
  • Significant new footwall intersections, including:
    • 23m at 1.35% Ni and 0.24% Cu from 235m
    • 18m at 1.17% Ni and 0.27% Cu from 293m including 11m at 1.71% Ni and 0.40% Cu from 299m
  • North-end of Sleeping Giant zone now interpreted to connect with L Zone with a new intersection of 33.7m at 0.61% Ni and 0.12% Cu from 21.3m, as above.

In September 2012 IMX Resources Limited reports the identification of twenty-five new high priority VTEM anomalies from the recently completed airborne magnetic and versatile time-domain electromagnetic (VTEM) survey over selected areas within the Nachingwea Nickel-Copper JV Project located in southeast Tanzania.

More..

Ntaka Details: http://www.imxresources.com.au/_content/documents/1246.pdf


Airborne EM and Magnetic Gradiometer for Palladium-Platinum-Gold Project in Timmins

Posted by AP on Friday, 14 December, 2012

Gold Dynamics Corp. contracted with Geotech Ltd. to complete a helicopter borne Versatile Time Domain Electromagnetic (VTEM Plus) and Horizontal Magnetic Gradiometer Geophysical Survey on the Hoyle North Palladium-Platinum-Gold Project located in Timmins, Ontario. A total of 84 line kilometers of geophysical data were acquired, flown at 100 meter spacing on the property.

Analysis of the preliminary data from the VTEM Plus indicate mineralized targets exist in the eastern portions and also a mineralized trend from the southeast to the northwest of the property at approximate depths of 200 meters. The survey also identifies a system of dykes which are very common in mineralized zones on this trend and are also common to the known geology of this area.

Further results and analysis are expected in the next few weeks. This information will be evaluated to select targets for ground follow-up in order to help prioritize anomalies for drilling.

Gary Kirk, CEO/President of Gold Dynamics Corp. said, “I am extremely pleased that we were able to contract with Geotech Ltd. who are a leader in their field, utilizing state of the art technology to help us build our base of knowledge on the Hoyle North project. With targets in hand, knowing the depth and location of these targets brings us much closer to finally drilling. The known geology common to the areas where other major international mining companies (Goldcorp, Xstrata Copper, Lakeshore Gold and Brigus Gold), whom are adjacent to our project, are currently producing large quantities of gold and other precious metals out of geologic structure very similar to what the VTEM Plus has identified in ours; is very encouraging for us.”

The Hoyle North property is contiguous to Goldcorp’s Hoyle Pond mine and is within short distances to significant resources such as Owl Creek and Bell Creek. The Hoyle North property remains relatively unexplored near to expansive mining and exploration efforts by significant companies such as, Goldcorp, Xstrata, Lakeshore Gold, San Gold, Osisko Mining and VG Gold and others.


Airborne geophysics results on Mexico’s Guerrero gold belt

Posted by AP on Saturday, 8 December, 2012

Citation Resources Inc. announces preliminary results of its airborne versatile time-domain electromagnetic (“VTEM“) survey completed in October 2012 over a substantial portion of the Biricu Gold Project located within Mexico’s Guerrero gold belt.

The VTEM survey was conducted by Geotech Ltd. and covered approximately 1,400 line kilometres at 150 metre spacing over three specific high-priority areas of the concession within a broader survey coverage at 200 metre spacing. Condor Consulting Inc. experts in the field of airborne electromagnetics, has been retained to perform a detailed interpretation of the results and their final report regarding the significance of the survey is still pending.

The preliminary interpretation by Condor has identified 19 potential target zones as defined by conductivity and magnetic geophysical anomalies on the Biricu Project. Six of these target zones are aligned along a 5 kilometer northeast trending corridor, which to date has only been partially ground tested. A field crew has been mobilized to conduct further mapping and sampling over the geophysical anomalies in order to prioritize areas for possible drill testing. Upon receipt of the final geophysical interpretation, the results will be integrated with the analysis of the field work completed and drill targets will be prioritized. The details of the final results will be presented in a future news release.