 
Short Summary:
The Arroyo Verde project is located in the Patagonia region of Argentina in the eastern part of Chubut Province. The property is well located with easy highway access.
The exploration potential of rhyolite dome complexes has been demonstrated repeatedly throughout Patagonia to be excellent. The known mineralization of Arroyo Verde occurs within one of the several rhyolite domes measuring approximately one kilometer in diameter. Gold-silver mineralization is located in major structures crosscutting the volcanic pile, localized at a geothermal hot spot with hydrothermal activity.
In previous exploration, drilling intersected three significant high level - low sulfidation epithermal gold-silver veins at depths of 25-50 meters over strike lengths of up to 40 meters.
Location:
Argentina: Chubut Province: 122 square miles
Climate: It's arid, near-desert environment and lends itself to year round field work.
Services: The closest common services are 55km north to Sierra Grande or 90Km South to Puerto Madryn. Both are fully serviced towns have lodging, restaurants, fuel and most common supplies.
|
Project Overview:
The Arroyo Verde project is located in the Patagonia region of Argentina in the eastern part of Chubut province just south of the border with Rio Negro Province. The property is easily accessible from the major paved coastal highway connecting Trelew in Chubut with San Antonio Oeste in Rio Negro. The climate is arid with the possibility of working year round. The property consists of three concessions totaling 5,378 hectares (20.7 square miles) covering a classic rhyolite dome field.
The exploration potential of rhyolite dome complexes has been demonstrated repeatedly throughout Patagonia to be excellent. The known mineralization at Arroyo Verde occurs within one of several rhyolite domes measuring approximately one kilometer in diameter. Its lithologies include massive and flow-banded rhyolites, flow breccias, talus, and tectonic breccias. Mineralization occurs within major structures cross-cutting in the volcanic pile forming a geothermal hot spot with known hydrothermal activity and gold-silver mineralization.
Geologically the property lies within the eastern part of the Somun Cura Massif. This is directly correlative to the Deseado Massif in Santa Cruz province to the South, where within the past five years a number of significant gold properties with high- grade vein systems have been discovered at Cerro Vanguardia, Huevos Verde, Manantial Espejo, and Mina Martha. Exploration has been concentrated in Santa Cruz Province where the majority of these projects are located. The north has only begun to see concentrated work with the discovery of the Esquel Gold Project in Chubut Province.
The Arroyo Verde project consists of exploration concessions totaling approximately 30,000 hectares (116 square miles) of concessions, located in eastern Chubut province, Argentina.
It hosts both gold-silver, in epithermal veins within an outcropping rhyolite dome complex, as well as the large Refugio-Porvenir molybdenum-copper porphyry system. Due to excellent access and infrastructure, the project is amenable to year round exploration.
The Principal Vein has been defined on surface over a 400m strike length grading 10.0 g/t gold equivalent over a 2m width (always calculated using a silver:gold ratio of 60:1 and metallurgical recoveries and net smelter returns to be 100%). Drilling has defined the vein over a 700m strike length to a depth of 300m. The sixteen drill intercepts within the main zone of the Principal Vein (defined as gold equivalent multiplied by true width being greater than 5) range from 0.53 to 3.77m in true width and grade 2.51 to 80.96 g/t gold equivalent, with a weighted average of 13.18 g/t gold equivalent over a 1.87m true width.
In addition, five drill holes intersected a new Hanging Wall (HW) vein south of the Principal Vein (PV) along a strike length of 150m with a width from 0.45 to 4.00m grading from 1.4 to 9.1 g/t gold and 31.1 to 316 g/t silver. The average width of this vein is 1.57m grading 6.81g/t gold and 271.7 g/t silver or 11.34 g/t gold equivalent.
Portal Resources plans to commission a study to calculate the resource of precious metals for the mineralized zones defined to date, both within the Principal Vein and the Hanging Wall Vein, based on present drilling.
Maps:
The El Refugio occurrence represents a grass roots discovery by the Portal team of a large molybdenum-copper porphyry system. Surface mapping and sampling defined coincidental geophysical anomalies as well as alteration zones typical of a porphyry system. Geophysical IP surveys have defined a large high chargeability anomaly 7km x 3km in size. Six drill holes in 2006 and 2007 defined a large molybdenum-copper system with significant intersections of up to 176m of 0.30% molybdenum. Additional work is warranted to search for areas of higher grade within this large, mineralized system. Portal is currently evaluating the option of seeking a joint venture partner to share the risk in further exploring such a large mineralized system.
History of Exploration:
Previous exploration on the property has focused on targeting bulk tonnage near surface mineralization with the following programs completed: geologic mapping, geo-botanical orientation surveys, soil and rock chip sampling; CSMAT, IP and Resistivity geophysical surveys; and drilling of 35 reverse circulation holes totaling 3,268 meters. This drilling intersected three significant high level - low sulfidation epithermal gold-silver veins at depths of 25 to 50 meters over strike lengths of up to 400 meters.
Geology:
Somuncura Massif Rock Types
Rocks that host the Arroyo Verde mineralization are felsic volcanics of the Marifil Complex, one of several age-correable volcanic sequences that make up two huge Jurassic volcanic outpourings or massifs of Patagonia. The Deseado massif, some 400 plus kilometers in diameter in Santa Cruz province, hosts several economic gold and silver deposits. The Somuncura massif, equally large, straddles Rio Negro and Chubut provinces and hosts a number of advanced gold exploration projects, including Arroyo Verde.
| 
