Prime Meridian Resources Corp.

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Winterfire
Overview
Prime Meridian has taken advantage of publicly archived past drilling data and availability of open mineral lands to acquire and advance the Winterfire Project, which lies in northern Minnesota a few kilometres south of the Canadian border. Although the geological setting of this Archean-age target does not strictly fit the Midcontinent Rift System (MRS) model, fortuitous drilling here by past explorers revealed sub-ore values of copper and nickel, as well as anomalous values of platinum group elements, in mafic intrusive rock units, all consistent with the criteria that define magmatic nickel-copper deposits. The company has taken leases covering all of the prospective terrane defined by the past drilling and by the heliborne aeromagnetic-EM survey it flew in the summer of 2007.

Project location, infrastructure and land tenure
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PMR Land / Drilling
The Project is in a sparsely populated part of northern Koochiching County, and lies about 6 kilometres south of the U.S.-Canada border, which is demarcated by the east-west Rainy River. On both sides of the border, the area depends primarily on beef cattle farming and logging, with some tourism, mainly summer fishermen. Minnesota Highway 11 more or less follows the south bank of the Rainy River between International Falls and Baudette, MN. Roughly halfway between these two towns, the hamlet of Birchdale on Highway 11 is four kilometres due north of the Winterfire target area. Access south from Birchdale is by a dead-end dirt road that ends at a large spruce swamp encompassing nearly all of the company's targets within the Project Area, where Prime Meridian has 550 hectares under lease from the State of Minnesota and a private landowner. Exploration activities involving machinery and drilling are by necessity a wintertime exercise at this aptly named Project.

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Geology
Regional Geology

Project Geology
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Winterfire Geology PMR Target Area
The Winterfire Project is located in an un-named granite-greenstone belt that extends northeasterly from northern Minnesota into Ontario, Canada. This belt is part of the Archean age Wabigoon Sub-province of the Southern Province of the Canadian Shield. There are few bedrock outcrops on either side of the U.S.-Canada border because of a covering of Pleistocene glacial deposits, the uppermost of which is a veneer of flat, poorly drained lakebed silt and peat derived from former glacial Lake Agassiz that tends to form swamps. The Pleistocene cover is about 30 metres thick, with rare small monadnocks of resistant bedrock units that once were probably islands in Lake Agassiz, such as outcrops of the Birchdale granite on Highway 11 four kilometres north of the Project Area. Besides the Birchdale granite, which is probably a small subvolcanic pluton, the rocks in the area are mostly known from drilling, and are primarily a greenschist facies metavolcanic and volcaniclastic sequence with an Algoma type iron formation at its base along the southern margin of the belt. The rocks are typical of Archean craton-acccreted island arc depositional sequences. The metavolcanics are bimodal, consisting of both metabasalt flows and felsic metatuffs, with locally included metasediments. In the Project Area, the greenstone sequence is steeply dipping and broken up into 3 large structural blocks by cross-faulting: the Northern, Central and Southern Blocks. Intruded into the greenstone sequence, and possibly co-magmatic with the basaltic units, are sill-like gabbro sheets that are the focus of Prime Meridian's exploration interest. These gabbros occur in both the Northern and Southern Blocks, but have not yet been encountered in the Central Block.

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History
This area has a long history of late 20th Century exploration, beginning with use of the earliest INPUT systems by Selection Trust and its partners (Milestone Joint Venture), searching for volcanogenic massive sulfide (VMS) deposits within the greenstones in the 1960's. Subsequent explorers on the American side of the border during the 1960's and 1970's included TexasGulf, Exxon Minerals and North Central Mineral Ventures (Superior Oil). Their programs were all directed at searching for VMS deposits, and were technical, but not commercial, successes. Drilling by these companies in the Project Area found bodies of greenstone-hosted pyrrhotitic massive sulfide with very sparse base metal mineralization; the best intercept was in a TexasGulf hole that returned 4% zinc in a 0.8 metre interval. However, some of the holes drilled by these companies encountered gabbro with magmatic Cu-Ni sulfides, the best of which was in an Exxon hole that graded 0.15% Cu and 0.10% Ni over 6 metres. In the late 1980's Normin Mining Company, the exploration arm of Boise Cascade Company, re-logged and re-assayed the Exxon drillhole and found anomalous platinum group element values in the gabbro interval. Normin followed this by ground geophysical surveys and drilling 6 holes in the Project Area, some of which encountered sulfide-mineralized gabbro.

In a 1995 gold exploration program on the Canadian side of the border, Nuinsco Resources inadvertently discovered nickel-copper in the #34 Zone, a very small (30 metres by 18 metres.) tubular shaped pyroxene-rich apophysis to a dike-like gabbro intrusion. Some spectacular drill intersections were reported by Nuinsco. Overall, the mineralized body had a weighted average grade from 9 drillhole intercepts of 2.2% Ni, 1.66% Cu, 6.43g/t Pd, 2.55g/t Pt, 2.32g/t Au and 18.46g/t Ag; no tonnage was reported. Nuinsco's #34 Zone discovery is in the same greenstone belt as Winterfire, and is 24 kilometres due north of it.

In 1998 the Minnesota Department of Natural Resources sponsored an enzyme leach soil and humus surface geochemical sampling study in the Project Area, using the old Normin grid. This study produced geochemical anomalies in a number of base metals, but these "anomalies" were only evident after sophisticated mathematical manipulation of the analyses, and there is poor spatial correlation between the results from humus and soil samples.

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Prime Meridian's Exploration Program
Aware of the significance of the Nuinsco discovery and of the reported values in the historic drill core from Winterfire, in 2005 Prime Meridian acquired private and State of Minnesota leases controlling the gabbro intrusions. It re-logged the historic drill core and made a reconstruction of the subsurface geology. From this work the company believes that the previous explorers missed the proper target in many of their drillholes, and in other cases, only obliquely intersected the edges of the sheet-like gabbros, failing to intersect the important basal zone. Prime Meridian also resampled core intervals of coarse grained gabbro with heavily disseminated and/or semi-massive net-textured sulfides composed mostly of pyrrhotite with lesser chalcopyrite and pentlandite. This re-sampling yielded grades ranging from 0.15% to 0.42% copper, 0.1% to 0.56% nickel, and anomalous platinum, palladium and gold in core intervals ranging from 4.7 metres to 12.8 metres.

The previous explorers' drilling was guided by geophysical techniques-of-the-day that lacked the depth penetration and interpretation capabilities of 21st Century systems. Mindful of that, in the summer of 2007 Prime Meridian flew an aeromagnetic-EM heliborne survey over the Project Area (see press release, June 28, 2007).

Current Plans
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Historical Drilling at Winterfire -- Tested Magnetics (gabbro) & One EM Zone
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3D Magnetics With Conductors Inserted -- Looking Northeast
Historical Drilling Did Not Test Main Conductors at Base of Magnetic Unit
** Note G-1,2,3 - Drillholes to Test PMR Targets at Winterfire
Prime Meridian's airborne survey produced several very strong anomalies in locations not tested by the historic drilling. The company believes that most of them represent basal gabbro magmatic sulfides. Six high priority targets have been selected for drilling, primarily on State of Minnesota land. The company is in the process of obtaining approval of an Exploration Plan from the State in order to do 2008 ground followup and drilling as seasonal conditions permit.

PDAC 2008 Presentation, CAMESE Innovation Forum

A paper including the Winterfire airborne geophysical and geological data was presented at the Prospectors and Developers Association (PDAC) 2008 conference in Toronto, one of the largest mining conferences in the world. The presentation was by Mr. Ken Witherly of Condor Consulting Inc. and titled "Integrating Geophysics and Geology in 3D". The Winterfire data was used as a case study. The Winterfire discussion begins on page 2 of the paper.

  • Integrating Geophysics and Geology in 3D



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