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Gold/Mining/Energy : Medinah Mining Inc. (MDHM) -- Ignore unavailable to you. Want to Upgrade?

To: Anthony J,Castellano who wrote (5131)	8/8/1998 5:48:00 PM
From: KMT	Respond to of 25548

Anthony: Hold on...show him what I'm about to post also... KMT

To: Anthony J,Castellano who wrote (5131)	8/8/1998 6:33:00 PM
From: KMT	Read Replies (3) \| Respond to of 25548

All: I'm retyping what I received on my FAX machine earlier today. It is a two page section from what I believe is a 60 page report by Gordon House. Please forgive any typographical errors. I also have some feedback from a few geology gurus. I like what they said to me but I'm not going to repost it yet. However, I may repost a brief summary of their feedback later. I'll let you all do your own interpretation of it and bring it to whomever you wish. ================================================= Summary Report on the Lipangue Breccia Zone and the relationship to Las Dos Marias Replacement Deposit by Gordon D. House, P.Geo. for Medinah Energy Inc. 7th August 1998 ================================================= The Altos de Lipangue Breccia Zone and Las Dos Marias "Stockwork" have been fully described in the "Report on the Evaluation of the Santiago Project, Metropolitan Region, Chile, for Medinah Energy Inc. dated 25th July 1998". The relationship between the two properties was indicated, and recommendations were made to follow up this relationship during the mapping programs recommended for both properties. Lipangue Breccia Zone The Lipangue Breccia Zone is a large hydrothermal, diatreme breccia pipe intruded at the contact between the Granodiorites of the Central Batholith and the intermediate volcanics of the Cretaceous "Formacion Lo Prado". The granodiorite batholith is of early to mid-Cretaceous age and may have been contemporaneous with the volcanics of the Formacion Lo Prado, the hydrothermal breccia pipe was intruded later and includes brecciated fragments of both rock types. Hydrothermal breccia pipes of this type are the surface expression of a late stage intrusive even which failed to reach the paleosurface, but the contained pressures in gases and hydrothermal fluids exploded to the paleosurface in a much smaller pipe punching up through the rocks above. Breccia pipes are associated with highly mineralized copper - molybdenum - gold porphyry deposits in many places, and are considered reliable indicators of mineralized intrusives at depth. In the case of the Lipangue Breccia pipe it is evident that the temperatures and pressures involved caused alteration of the fragments in the breccias, the relief of these pressures after the pipe had exploded onto the paleosurface resulted in complex physicochemical reactions within the hydrothermal gases and fluids venting to the surface. The breccia fragments were coated with crystals of quartz as the pressure dropped, the gases and fluids continued venting with hydrothermal fluids passing more slowly through the breccia pipe depositing contained sulphides in the form of pyrite and chalcopyrite. The hydrothermal fluids carried other sulphide minerals as well as gold, silver and mercury in solution, these minerals were deposited in the spaces within the breccia pipe eventually cementing the whole into a solid rock mass. The mineralization present in breccia pipes is not always representative of the mineralization in the source intrusive body, in many cases trace element geochemistry will indicate associations with mineralized copper - molybdenum - gold porphyry deposits. Such geochemical analyses were not carried out during the evaluation of the Santiago Project properties but samples taken will be re-assayed in the future. The existence of a hydrothermal breccia pipe is considered indicative of a mineralized porphyry copper-molybdenum-gold deposit at depth, which caused the breccia pipe by explosive degassing. Las Dos Marias Replacement Deposit The deposit known as Las Dos Marias is located on Quebrada Durazno, about 2.0 to 2.5 kilometers to the east of the Lipangue Breccia pipe and lies within the same Cretaceous Formacion Lo Prado of intermediate volcanic tuffs and lavas. Las Dos Marias has been variously described as a "stratiform Skarn" deposit and a "stockwork" deposit, however the underground exposures in the old workings on the east side of the creek are clearly stratabound replacement deposits where hydrothermal solutions penetrated through porous or receptive horizons within the volcanic stratigraphy. These stratabound deposits are well known in Chile where they are called "mantos", such "manto" deposits were and are the source of much of the copper and gold mined in the Andacollo area in Region IV near La Serena and Coquimbo. Las Dos Marieas deposit is a manto type deposit, a replacement deposit where hydrothermal solutions emanating from a late stage intrusive event, such as the Lipangue Breccia pipe, percolated through porous or permeable volcanic tuffs or lavas and deposited the hydrothermal solutions were able to replace permeable volcanic tuffs or lavas and deposited the contained copper and other metal sulphides by replaceing minerals in the host rock. The hydrothermal solutions were able to replace permeable volcanic rocks without causing extreme alteration of the less permeable or impermeable rocks within the stratigraphic column, thus there are barren horizons between the "mantos" in the deposit. The source of the hydrothermal fluids at the Las Dos Marias deposit is not known at present, but the relatively close proximity of a late stage intrusive event as represented by the Lipangue Breccia pipe suggests that the intrusive under and causative of the breccia pipe may be the source. Las Dos Marias is located 2.0 to 2.5 kilometers east of Lipangue Breccia pipe and is from 500 to 700 meters lower in elevation , and perhaps the lower levels of the breccia pipe, if not the intrusive body itself, was the source of the hydrothermal fluids. It is worth noting that in the Andacollo area the "manto" deposits are located in favourable horizons up to 5.0 kilometers distant from the Andacollo porphyry copper depost, which is believed to have been the source of the hydrothermal fluids which deposited the "mantos". The distance of "manto" deposits from the source of hydrothermal fluids is not a problem, it is the availability of favourable permeable volcanic horizons in the country rock that is essential to allow the hydrothermal fluids to move away from the source. The contained sulphide minerals are deposited from solution when the physico-chemical conditions change sufficiently through cooling or release of pressure, replacing the rock forming minerals to form the "mantos". The relationship of the Lipangue Breccia pipe to the "manto" deposits at Las Dos Marias is not proven, it is strongly suggested by the proximity of the one to the other and the hydrothermal breccia pipe representing the top of a late stage, mineralized intrusive event. In our Report we recommended that the geological mapping and geochemical sampling on Las Dos Marias deposit attempt to determine if there is a link between the two deposits. The geophysical program recommended for both properties may show that the "mantos" at Las Dos Marias do extend to the west towards the Lipangue Breccia pipe, in which case it would be worth while carrying out diamond drilling to trace out the manto deposits to the west. The two deposits, at the Lipangue Breccia pipe and Las Dos Marias "manto", appear to be related and future exploration programs should be used to confirm this relationship. The Altos de Lipangue plateau is a well mineralized district, there are many small quartz vein deposits within the 4.5 x 1.5 kilometer extent of the plateau and most of these deposits do have an affinity with classical porphyry copper-molybdenum-gold deposits. This indicates there was a strong hydrothermal mineralizing event in the district, the Lipangue Breccia pipe is the marker part of this event. Gordon D. House, P. Geo.