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IInitial Exploration on the Iliamna Project was conducted in year 2000 by Rio Algom Exploration Inc., which was subsequently taken over by BHP Billiton. The program consisted of a regional airborne magnetic survey followed by reconnaissance geology and wide-spaced Induced Polarization/Resistivity surveys in selected areas. BHP Billiton's results suggested that this project has the potential to host a porphyry gold-base metal deposit similar to the nearby Donlin Creek deposit held by Novagold Resources, and the Pebble deposit held by Northern Dynasty Minerals Ltd. The Pebble deposit, discovered in 1987 and held by Northern Dynasty Minerals Ltd., has an measured and indicated mineral resource of 31 million ounces of gold and 18.8 billion pounds of copper, making in one of the worlds largest deposits of its kind. Initial target definition at Pebble occurred in areas covered by glacial overburden and/or Tertiary volcanic rocks, as is the case at the Iliamna Project. Targeting was based on the recognition of magnetic anomalies representing possible covered intrusive complexes. Additionally, BHP-Billiton's geophysical results are similar to the response of geophysical surveys that led to the discovery of the Pebble deposit. Subsequent drilling at Pebble intersected the gold-copper mineralization identified by the geophysical work. Geocom intended to follow a similar exploration plan and completed drilling in 2004, 2005 and 2006.
An NI 43-101F1 technical report is currently being updated and will be filed on Sedar. A total of almost US $2 million has been spent since 2004 on the exploration by all the partners. Goldmark will now lead the project and continue with more geophysical work and drilling on the D and H claims. The property was staked primarily for its copper and gold potential. The claims cover 314 sq km of land. Subsequent exploration work indicates a strong possibility that of encountering skarn mineralization proximal to the contact of any intrusives. While decent indicators of mineralization have been found on the property, to date no economically significant mineral deposits have been found.
Regional work by state and federal geologists has been done in all four quadrangles covering the Iliamna Project area; however, there is presently no published geological map for the Dillingham quadrangle. Regional mapping indicates the project area straddles the boundary separating two distinct geologic terranes; the Peninsular Terrane to the southeast and the Kalitna Terrane to the northwest. The terranes were joined during late Cretaceous-early Tertiary time, with the suture zone marked by the Lake Clark-Castle Mountain Fault. The rocks underlying the project area include:
- Tertiary volcanics
- Jura-Cretaceous flysch sequence (lower greenchrist facies)
- Jurassic Volcanic rocks (Peninsular Terrane only)
- Triassic volcanics, limestone, chert
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These rock assemblages were intruded by Jurassic- to Tertiary-age plutons, dikes and sills. The major intrusive episodes occurred during the Jurassic Period (175-155 mybp) which intrusive rocks lie south of the Lake Clark Fault, the mid to late Cretaceous Period (90-70 mybp) which includes the 90 million-year-old Pebble intrusive complex, and early through late Tertiary time. The Tertiary age intrusive rocks are closely related to extrusive volcanic events of the same age. |

Geologic mapping and geophysical work indicates that the dominant structural grain in the area is NE-SW although N-S, E-W, NW-SE and NNE-SSW lineaments also occur in the region.
Gold mineralization at the Pebble deposit occurs within a late Cretaceous intrusive complex made up of stocks, dikes, sills and other intrusive rocks hosted by Jurassic-Cretaceous sedimentary rocks. The gold-base metal mineral inventory at Pebble contains 21 million ounces of gold and 6.8 billion pounds of copper.
The exploration target at Iliamna is a gold-enriched porphyry deposit. Nearby and district level examples include the Pebble deposit (21 million ounces of gold) held by Northern Dynasty Minerals Ltd. It is one of the world’s largest mineralized gold- and gold-base metal-bearing systems.
In year 2000 Rio Algom carried out several phased exploration programs including an airborne magnetic survey, reconnaissance geology, and IP/Resistivity surveys. These surveys led to the successful identification of several geophysical anomalies, including the Iliamna Project. The airborne magnetic survey successfully outlined three regional anomalies: the Pebble intrusive complex, the Nushagak anomaly, and the Kvichak anomaly, which includes the Iliamna property. Following the regional geophysical programs, site-specific IP/Resistivity Surveys targeted and successfully located several anomalies that are similar in size and characteristics to the Donlin Creek and Pebble deposits, including the Iliamna Project.
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A reconnaissance geologic program in the area ground-checked numerous large and small magnetic anomalies defined by the Rio Algom survey and several identified in an earlier U.S. Geological Survey quadrangle inspection program. This geologic inspection confirmed the geophysical anomaly at Iliamna by examination of outcrops and magnetic susceptibility testwork. |
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