Posts Tagged Terraquest

The Magnetic/VLF survey in Newfoundland

Posted by on Thursday, 18 October, 2012
Silver Spruce Completes Airborne Survey and Receives Check Assays for the Big Easy Gold/Silver Property, Eastern Newfoundland

Silver Spruce Resources Inc. announces that the high resolution magnetic / VLF-EM airborne survey has been completed and preliminary results received on the road-accessible, Big Easy gold/silver property in eastern Newfoundland. The Big Easy prospect is a large, altered (silicified) system that covers an area of approximately 1.7 kilometres by up to 300 metres wide.   The prospect was drilled in 2011 and 2012 — a total of 12 holes over a 1.2 km strike length, giving significant gold (Au) and silver (Ag) values in a number of the drill holes (news releases September 18, 2012, August 16, 2012 and June 7, 2011).

Airborne Survey
The airborne, high resolution magnetic / VLF-EM survey was carried out in late September by Terraquest Ltd. of Mississauga, ON.    The aim of the survey was to improve the understanding of the geological setting of the area by a lithological/structural interpretation based on the survey results, drilling and surface geology.

The preliminary magnetic data shows a broad, NNE (025 degrees) magnetic high trending through the main portion of the claim group with narrow linear, NNE trending magnetic lows within the overall magnetic high.   The magnetic  lows are offset by linear zones and possible dikes / faults, trending NNW (340 degrees). A sinuous magnetic  low joins the BE and ET zones, continuing to the south of the ET zone.    The preliminary VLF-EM data shows NNE and NNW trending, as well as a number of E-W to ENE-WSW trending conductive zones cutting through the property.

“We are pleased with the resolution of both the magnetic and VLF-EM data.    Based on what we are able to tie into our existing geological and structural compilation, the final results should enable us to better target continued exploration, including drilling,” states Peter Dimmell, President and CEO of Silver Spruce Resources.

Line spacing was 200 m in the known mineralized areas (Big Easy and ET) and 300 m over the rest of the property, at a mean terrain clearance of approximately 70 m. The survey was flown using E-W lines and N-S tie lines for a total of 349 line km. The VLF-EM used two orthogonal receivers, with the main transmitter Cutler, ME.

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Complex airborne survey in Suriname

Posted by on Wednesday, 28 September, 2011

Hunter Bay Minerals plc  announces the completion of its airborne geophysical survey at its Sela Creek Project, Suriname. The 4,986 kilometre aeromagnetic, radiometric and XDS VLF-EM survey was conducted by Terraquest Ltd. and indicates that areas of known mineralization are coincident with magnetic and radiometric anomalism. Using this geophysical signature and first pass field work, Hunter Bay has identified three high priority targets for immediate follow up work: Central Ridge, Jons Pit-Texas trend and Eastern Anomaly.

Aeromagnetic data (Figure 1) indicates that the broad area containing the three high priority targets occurs within a regional scale, rhombic dilational structure approximately 20 kilometres long and up to 8 kilometres wide, bounded to the north and south by west-northwest trending shear zones. Preliminary interpretation, combined with field observations from limited outcrop, suggests that the mid-range subdued magnetic response within the rhombic structure is associated with deeply weathered metasedimentary rocks intruded by dioritic, granodioritic and tonalitic intrusions.

Many of the known saprolitic workings occur either at the inferred contacts between metasedimentary rocks and intrusive bodies or cluster along a 5 kilometre, northwest trending structure called the Jons Pit-Texas trend. These observations highlight the importance of intrusion-related targets at Sela Creek and the structural controls on mineralization. In detail mineralization is spatially related to localized magnetic lows and coincident high potassium radiometric anomalies, which are interpreted to represent areas of hydrothermal alteration (Figure 2).

Central Ridge is a 2 kilometre long, east-west trending magnetic low bounded by moderate intensity magnetic highs, located immediately northwest of the Jons Pit-Texas trend. This magnetic anomaly coincides with a 5 kilometre long, east-west trending ridge which forms the watershed between several prominent north and south draining creek systems. These creeks have been extensively mined for alluvial gold. Central Ridge represents a high priority target for follow-up soil sampling and mapping.

Eastern Anomaly is a new high priority target in the eastern part of the licence. Eastern Anomaly comprises a 2 kilometre long, northeast trending magnetic low and coincident potassium high, which is a similar geophysical signature to that observed at the Jons Pit-Texas trend.

In conjunction with the Terraquest airborne survey, Hunter Bay also conducted aerial reconnaissance using a Cessna light aircraft which has provided a better understanding of the spatial extent of mineralization defined by artisenal workings in saprolite. In particular, shear-hosted and structurally-controlled mineralization is more extensive than previously mapped and in some places artisenal workings define up to 3 sub-parallel mineralized zones with a combined surface expression of up to 100 metres wide and over 1 kilometre long (Figure 3). Collectively artisenal workings define a broadly northwest trending corridor approximately 5 kilometres long and 1.5 kilometres wide (Jons Pit-Texas trend). Small areas of artisenal working are also present in the north and west of the licence and represent new showings which had not been previously identified.

Hunter Bay is presently completing additional processing and more detailed interpretation of the geophysical data in order to further identify and prioritize geophysical targets. An extensive soil sampling and follow-up mapping program is to commence in July 2011. Data collected during this stage of the program will be used to plan a reconnaissance drilling program.

To view the three images associated with this release, please click the following link:

Ground geophysical surveys based on 2005 High Resolution Aeromagnetic Survey

Posted by on Friday, 7 January, 2011

Champion Bear Provides Exploration Update and Plans for 2011.

Detail High Resolution Aero-magnetics, Horizontal Gradiometer, Radiometrics and XDS/VLF-EM for Creso

Posted by on Thursday, 1 July, 2010

Creso Exploration Inc. announces the award of a 5000 meter drilling program on the Shining Tree properties that will start this week including deepening by a further 300 m the Minto Hole #2 (18.2 g/t Au over 65.7 meters from 49.3 m to 115 m and 4.61 g/t Au over 79.6 meters from 132.4 m to 212 m – see) in order to do more down-hole geophysics and better delineate the gold bearing zone. Concurrently, Creso will initiate a detailed helicopter survey at 30m line spacing that will focus primarily on the Minto, Matona, Tyranite and Duggan Zones to outline known gold mineralization areas.

Creso has signed two airborne geophysical contracts with Terraquest Ltd both of which will start in July. The helicopter survey which will include Single Sensor High Resolution Aero-magnetics, Radiometrics and XDS/VLF-EM systems is based on 1779 line kilometers to be flown at low altitude with a 30m line spacing. The fix-wing aircraft will survey the entire eastern half of the Shining Tree properties covering large areas of the Tyrrell, Knight and Milner Townships survey and will include High Resolution Aero-magnetics, Horizontal Gradiometer, Radiometrics and XDS/VLF-EM systems over 5853 line kilometers at a 100m line spacing.

The combination of these two surveys is particularly well adapted to the Shining Tree Area where contrasts in hydrothermal alteration, mineralized volcanic and intrusive rocks, and complex structural features are common. Radiometric surveys will aid in delineating potassium enriched alteration zones commonly associated with gold mineralization in the area.

Results of Dog Lake Geophysical Survey

Posted by on Saturday, 26 June, 2010

Auric Mining Corp. announces the results of an Airborne magnetic and VLF-EM Survey conducted for the company by Terraquest Ltd. of Markham Ontario. Terraquest Ltd. was contracted to perform a VLF Electromagnetic survey of the Company’s property in the Dog Lake area of Northern Ontario.

The survey confirmed a number of gold showings on the shoreline of Dog Lake, located a few hundred meters to the west of the property boundary. In the past there has been considerable ground geophysics and drilling conducted in this area. The magnetic maps show the presence of narrow magnetic linear features striking from a North to East trend and appear to occupy all of the three major rock types. At least ten diabase dykes have been interpreted from the second derivative pattern and almost all are certain to belong to the Matachewn-Hearts swarm that is prevalent in the area. In the southeast corner a lateral displacement of three dykes are interpreted as a fault.

One of the more significant features of the magnetic maps is the presence of narrow magnetic linear features striking from North to East. These are illustrated on the interpretation maps and appear to occupy all three major rock types. The OGS map shows several major faults or deformation zones in the general area and with the same strike direction. It is proposed that these magnetic linears could be related to them. They could represent fracture elements in a broad deformation zone and since they stretch into the gold showings to the west are of considerable interest now as possible channels of mineralization.

Based on the conclusions and recommendations of the VLF-EM survey, possible new exploration targets have been identified and further exploration recommended. An exploration program has been adopted and will be carried out in the coming months.

Auric Mining Corp. plans to do another similar survey in the near future using additional technology to better define these results before a full field exploration program commences this summer.

  • Previous exploration in the Wawa has discovered numerous deposits of small diamonds within metamorphosed Archean basement rocks.
  • Dianor has discovered rocks with encouraging grades and stone size distribution directly south of the Mori-Metalex ground.
  • Island Gold Mine has Proven and Probable Reserves of 1,013,854 tonnes at a grade of 8.55 g/t gold for a total of 278,711 ounces of gold (NI 43-101 compliant report by GENIVAR) Project has additional Measured and Indicated Resources 454,705 tonnes at a grade of 10.26 g/t for a total of 149,972 ounces (NI 43-101 compliant report by GENIVAR).

Complex airborne survey in the Sudbury Basin

Posted by on Saturday, 5 June, 2010

Trueclaim Exploration Inc.  an explorer and developer of precious and base metals,  announces the completion of preliminary results of the airborne geophysical survey undertaken on the property and a summary of its activities on the Scadding Property.

The preliminary data from the recent airborne survey undertaken on the Scadding property and surrounding area has now been received, geo-referenced and overlain with our in-house interactive digital map base consisting of the underlying topography, claim fabric, geology maps, known mineral occurrences and other layers and classes. This survey, consisting of 2,943.9 line kilometres and covering an area of approximately 244.3 square kilometres, was undertaken by Terraquest of Markham Ontario. This survey was comprised of a total field magnetometer survey, horizontal gradient magnetometer surveys, a radiometric survey for each of Potassium, Thorium and Uranium as well as their recently developed triaxial VLF survey. Variations in the strength of the magnetic field have been used for to determine different rock types or alteration zones that could be related to gold mineralization. The variations in potassium content can be used to discriminate rock types as well as locating zones of anomalous potassium content (potassic alteration) within lithologies that normally have low values of this element. Potassic alteration has, in some cases, been known to be associated with gold mineralization. The triaxial VLF survey will allow for the better discrimination of conductors in a variety of orientations. The area of the survey included peripheral properties of several claim holders who also participated in the cost of the survey over their properties. At this time further work is being undertaken by Terraquest to enhance the quality of a final product.

The results of the preliminary geophysical interpretation of the survey show numerous anomalies that are now being examined on the ground by our field crews. Each person in the field has been equipped with a Garmin Map 60CSx handheld GPS units containing detailed 1:20,000 scale topographical maps of the area to ensure accurate and efficient location and examination in the field.

At this time three teams are simultaneously working on the property. Team 1 consists of a geologist and helper currently stripping, washing and mapping in the immediate area of the Scadding minesite to enhance information collected from our phase 1 drill program to be combined in our existing 3D model for enhanced targeting in the proposed phase 2 drill program. Team 2 consists of a geologist and 2 prospectors who are currently examining and sampling airborne anomalies and other sites outside the area of the Scadding minesite. The information collected from this work will be used to determine the best areas for further examination by detailed ground geophysics, geochemistry, stripping, washing, mapping and potentially diamond drilling where warranted. Team 3 consists of the senior geologist and a logistics coordinator and is focused on co-ordination of field activities, collection of data, preparation and submission of data as well as assessment reporting. Currently in addition to the submission of upcoming assessment work, detailed local sitemaps are being prepared for the examination and mapping of the many known gold, base metal and platinum group metal showings known on the site.

A geochemical and magnetic susceptibility analysis of the core was also undertaken comparing some of the gold mineralized areas with non-mineralized areas. This study has revealed some interesting correlations that are currently being studied further. It is felt that the results of this work may help in discriminating non-mineralized chlorite from the mineralized chlorite in which most of the gold occurs at the minesite.