Newsletter #3, November 1999
The McGill University Student Chapter of the SEG had a busy and successful 1998-1999. Membership remained constant at about thirty with the majority made up by undergraduates. This bodes well for the future of the Chapter to have so many keen and eager members for future years. Corporate membership of the Chapter increased considerably, and this much appreciated financial assistance allowed us to organize more mine visits, field trips and guest lecturers than the previous year. The new officers voted in for the 1999-2000 year are: Katherine Ault (President), Jae Jong (Jane) Kwak (Vice-President), Martin Heiligmann (Treasurer), and Keith Yaxley (Secretary). Activities of the last session included a field trip to Noranda's Mines Gaspé, at Murdochville. This trip was attended by 12 members and was well worth the ten hour drive to the mine site. In March, 22 members and faculty sponsor A.E. Williams-Jones went on the annual Latin America field trip, which this year was to Ecuador. Immediately after this trip, several members were in attendance at the PDAC meeting in Toronto. The McGill Student Chapter of the SEG presented a poster of the Chapter's activities in the hospitality suite hosted by McGill's Department of Earth and Planetary Sciences, in the Royal York Hotel. This is also planned for the coming conference in March 2000. The Chapter was also pleased to invite three speakers to McGill, who gave presentations on a variety of subjects including sediment-hosted copper deposits, BIF-hosted gold-palladium deposits, and gold mineralization in greenstone belts. This year a total of four speakers will be discussing topics such as Canadian diamond deposits (H. Helmstaedt, November), Olympic Dam -type mineralization in Canada (T. Birkett, January), gold mineralization in the Appalachians (B. Dube, February), and precious metal mineralization in the Circum-Pacific region (J. Hedenquist, March/April). Seven members decided to take part in a day trip to pan at the historic placer gold mineralization near Beauceville, south of Quebec City. We are hoping to make this a regular feature of the Student Chapter, as it gives students some hands-on training in a traditional exploration technique. The highlight of activities planned for this year will be a proposed trip to some classic mining areas in Nevada and Arizona, as well as several Ag, Cu and Au mines. Other areas of interest include the Grand Canyon, Death Valley and the meteorite crater at Canyon Diablo. A few spaces on this field trip will be reserved for representatives of company sponsors of the McGill Student Chapter of the SEG. Also, special agreement has been reached with McGill Petrographic Laboratory where companies sponsoring the Student SEG Chapter will receive a 20% discount on all work performed in the laboratory.
SEG Seminar Series Greenstone Gold Deposits and their Diversity
The first speaker of the new academic year was Dr. Francois Robert of Barrick Gold Corp. who gave his presentation, "Greenstone Gold Deposits and their Diversity" on October 1st 1998. Dr. Robert discussed the characteristic of mesothermal load gold systems such as alteration (quartz-carbonate-tourmaline), metal ratios (high Au:Ag), metamorphism (greenschist facies), tectonic setting, structural relationships, age, and proximity of igneous rocks of comparable age. The examples that Dr. Robert used were from the Abitibi Greenstone Belt in northern Quebec, with particular emphasis on the Sigma, Bousque, and Young-Davidson mines. He then talked about the influence that sediments may have played in the role of mineralization, and related this to the Timiskaming sedimentary rocks associated with the Destor-Porcupine fault. Other deposits outside the Abitibi area that were presented during the talk included Hemlo (Ontario) and Porgera (Papua New Guinea). Dr. Robert suggested that syenite source rocks may be the reason that these particular deposits are enriched in Au, Ag, Te and Sb.
Vice-president Nick Barnes gave the vote of thanks after a stimulating question period to the speaker. Geology and Genesis of the White Pine Sediment-Hosted Stratiform Copper Deposit Professor Alex Brown (Ecole Polytechnique) was our second guest speaker of the semester in mid-November where he presented "Geology and Genesis of the White Pine Sediment-Hosted Stratiform Copper Deposit". Professor Brown gave the audience an interesting talk on this classic Proterozoic sediment-hosted deposit in Michigan. The talk began with an historic overview of the White Pine deposit, from aboriginals working the nearby native copper of the Keweenaw Peninsular (within basalt), until the US government funded exploration and mine development during the Korean War. The mine operated from the early 1950's until 1995 with a total production of 560 Mt at 1.2 % copper. The ore was mainly chalcocite (87%) with the remainder being native copper (13%). Professor Brown talked about potential source rocks for copper and ligands (Kewinawin Basalts and evaporites from the rift sequence) and the delta sequence of the Nonesuch shale, and bounding red beds, in which the mine is hosted. He then integrated this evidence to explain mineralization at White Pine in terms of two proposed models (syngenetic or epigenetic), and discussed his reasons for the epigenetic. Professor Brown pointed out that this class of deposit accounts for 25% of the world's copper production. Other examples of this class include the Zambian Copper belt (Zambia), Kuperschiefer (Poland, Germany) and Dzhezkazgan (Russia). At the end of the talk Professor Brown was pleased to answer the numerous questions which were asked regarding this deposit and other deposits that he had studied.
Sandy Archibald proposed the vote of thanks.
Palladium-bearing gold deposits hosted by Proterozoic Lake Superior-type iron formations of the Itabira District, Brazil
The Chapter was very pleased to invite Dr. Gema Olivo (a consultant geologist based in Bathurst, NB; now an Assistant professor at Queen's University) to McGill in March to present her talk entitled "Palladium-bearing gold deposits hosted by Proterozoic Lake Superior-type iron formations of the Itabira District, Brazil". Gema, a native of Brazil, was well known to all present as she had recently completed a post-doctoral fellowship with faculty sponsor A.E. "Willy" Williams-Jones. She started her talk by introducing the audience to banded iron formations and talked about factors leading to gold and palladium mineralization. The talk then focused on the Cauê mine in the Itabira District, where we were shown slides demonstrating metamorphic and structural relationships. Production at the Cauê mine in 1994 was 5.62 tonnes of gold and 0.39 tonnes of palladium, and was mainly produced from a rock type locally known as Jacutinga, occurring with the Itabirites (metamorphosed B.I.F.). Jacutinga contains the alteration assemblage of talc, phlogopite, quartz, hematite and tourmaline, and is named after a local black bird with white spots that the host rock resembles. The precious metal ore occurs along the S1 fabric and is refolded in the D2 deformational event. Local concentrations of gold within the "Y" ore body have contained up to 7 kg/tonne ! Mineralization is further enhanced by extreme to a depth of 500m, resulting in silicates altering to kaolinite, iron oxides to iron hydroxide, and ore minerals becoming oxidized and remobilized. Gema explained the likely ligands (Cl) for the Au and Pd and the mechanisms which would lead to their precipitation. The talk was concluded by Gema suggesting that this type of mineralization should be classified at "Jacutinga-type" as it is distinct from other Au-Pd-rich banded iron formations.
Sandy Archibald proposed the vote of thanks.
Gold Panning in the Eastern Townships
Seven Chapter members were busy during the third week of June trying their hand at the ancient art of gold panning in the Gilbert River, south of Québec City. The idea of the trip was to give the Chapter members some experience of gold panning as only one of them had actually panned before. The Gilbert River, a tributary of the Chaudière River, was the site of the largest gold placer mining operation east of the Rockies in the late 1800's. It is estimated that the region produced up to 2300 kg of gold since major production started in 1862 until the last mining operation terminated in the 1960's. After a quick instruction of how to pan by Sandy (i.e. where to find the auriferous gravel, how to reduce the pan concentrate, and once you have found gold, how to actually pick up this microscopic flake!) the group went on their merry way on striking it rich! The weather was fantastic with temperatures in the 90's, a cloudless sky, and a slight breeze. Unfortunately, as the strain of panning took its toll a couple of people started suffering the effects of heat stroke and had to retire from the proceedings. The stage was then set for the sour-doughs to find some colours in the paydirt. Due to the extensive mining earlier in the century much of the coarse gold had been collected leaving the finer material, which had escaped the dredges and sluice-boxes. It were these flakes which Sandy, Glenn, Ghislain and perhaps Alex (the jury is still out) recovered from the streambed. No actual nuggets were found only very fine flakes. The amount of work carried out on the river by earlier prospectors and miners was evident due to the quantity of magnetite which was panned, suggesting the area had been extensively work before, thus concentrating the magnetite. The provenance of the gold collected is interpreted to be local in origin, probably derived from Appalachian aged mesothermal mineralization that cuts gabbros in the area. Everyone agreed that they had a good time, although not everyone found some gold. It is hoped to make gold panning in southern Québec a regular activity during the summer as it is good fun as well as teaching Chapter members a skill which can be applied during mineral exploration work.
Alex Fitzpatrick getting down to the finer points of gold panning
Sourdoughs in action on the Gilbert River (please note the effects of heat-stroke on Mark!)
Field trip participants. Jae Jong (Jane) Kwak, Kate Ault, Glenn Poirier, Mark Nelson, Ghislain Lefebrve (with pan), Sandy Archibald and Alex Fitzpatrick
Ecuador Fieldtrip
Twenty-two members of the McGill Student Chapter of the Society of Economic Geologists participated in a field trip to Ecuador, led by professors A.E. Willliams-Jones and R. Doig. The Chapter has visited many Latin American countries where mining is active, and it was felt that Ecuador provided the opportunity to study the geology of a relatively unexplored country. During our tour, we were met by socioeconomic crises such as gasoline shortages and freezes on currency, yet even in the midst of these difficulties, we managed to travel extensively throughout the Andean backbone and observe geology on both regional and local scales. The geology of Ecuador is dominated by numerous volcanic centers and our trip focused on the relationship between volcanism and mineralization. This was achieved by numerous outcrop observations, a visit to an advanced prospect (including core shack), as well as visits to active volcanoes and hydrothermal systems. A variety of terrains were observed throughout the trip, including the windswept Pacific coast, snow-clad Andean Cordillera, and the humid upper reaches of the Amazon Basin. Our first destination was to Quilotoa, a volcanic crater lake located south of Quito. We hiked into the crater through paths of sedimentary ash deposits and upon reaching the lake shoreline observed silicified fumarole zones. This environment is often associated with high-sulphidation precious metal mineralization. In Cuenca, IAMGOLD Corp. hosted the Chapter for a visit of their San Francisco property. Richard Spencer, head of the exploration, explained that gold mineralization on the property is associated with an epithermal high-sulphidation breccia of Miocene age. The close proximity of the prospect to a Miocene volcanic crater suggests an ancient analog to Quilotoa. Mineralization is hosted by quartz-alunite alteration within fracture zones around the caldera margin, and consists of native gold and minor electrum. Gavin Daye, structural geologist with IAMGOLD, discussed the tectonic and structural history of the prospect in relation to the regional setting. A visit to the core shack in Cuenca allowed participants to view samples from two regions of the property showing different styles of brecciation and mineralization. Stops at roadside outcrops were an integral part of the field trip and a multitude of volcanic and volcanoclastic features where observed, ranging from thick rhyolitic flow sequences to thinly bedded pumice and lapilli beds. All these features provided useful clues to the tectonic and magmatic processes occurring within the Andean Cordillera. The highlight of the trip was a strenuous hike to the summit of Guagua Pinchincha (4800m), an active composite volcano located 10 km from Quito. Those who reached the summit witnessed, from a safe distance, fumarolic activity and a minor phreatic explosion. We are grateful for IAMGOLD Corp. for their hospitality. Additional thanks to The Society of Economic Geologists, Cominco Ltd., Inco Ltd., and Kinross Gold Corporation for their generous financial contributions. Jae Jong (Jane) Kwak and David Mapp
Gavin Daye, geologist from IAMGOLD, explains the geology of the San Fernando property to field trip participants
Mines Gaspé Fieldtrip
Our Fall field trip, held in mid-November, consisted of a visit to Noranda's classic Mines Gaspé copper skarn deposit at Murdochville, Québec. Sixteen Chapter members were in attendance for the 1800-km round-trip, visit to the Gaspé area. Chief Geologist Jeff Hussey welcomed everyone to Mines Gaspé, and gave the participants a one-hour talk on regional and local geology, as well as the exploration history of the Murdochville area. In 1921, Alfred Miller (a prospector) and his brothers organized an expedition to find the source of copper bearing boulders found in 1909, in the York River. This search led them to Copper Mountain where the mineralization was exposed. Exploration in the area continued through the depression and pre-war years, and culminated in the discovery of disseminated and stratiform Cu mineralization beneath Copper and Needle Mountains, respectively. Preliminary ore reserves were estimated for these two areas to be 19.5 Mt grading 0.93% Cu. Exploration was interrupted in 1940 due to World War II, and not resumed until 1946. In 1947 drilling at Needle Mountain encountered 43.8 Mt of ore grading 1.54% Cu, this discovery prompted James Murdoch, president of Noranda Mines Ltd, to initiate mining at the site in 1951. Other significant discoveries were made in 1961 and 1971, which resulted in the delineation of an additional 209 Mt of ore grading 0.40% Cu and 0.02% Mo at Copper Mountain. The mineralization is hosted by Early Devonian calcareous sedimentary rocks and occurs within the Copper Brook aureole, a roughly 3 x 2.5 km bleached alteration zone that plunges steeply towards the north. This alteration is associated with a deep-seated, syn-Acadian, porphyritic biotite granodiorite intrusion. The surface exposure of this intrusion is the Copper Mountain plug, and the Porphyry Mountain diatreme breccia. The alteration zone is composed mostly of light grey marble and calc-silicate hornfels. Mineralization is present in four types: early massive-disseminated sulphide replacement of marble and hornfels; disseminated to semi-massive sulphides that replace marble; porphyry copper-style sulphides; and late retrograde vein sulphides. After the excellent introduction by Jeff, coffee and cookies were on hand to fortify the participants of the next part of the trip, two-hour underground mine tour. Once everyone was fitted with the required safety equipment we were driven underground to the 40m thick C-zone. This zone is massive in nature, has a grade of 3.2% Cu, and is present within a garnet-clinopyroxene skarn which replaces the L1 limestone unit. The second stop was within the E-zone where disseminated sulphides adjacent the skarn (manto-type) were observed. The last stop was within the B-zone where the siliceous mudstone had been metasomatized into a wollastonite skarn. An added attraction at this stop was watching the drillers prepare holes for blasting. Throughout the underground tour Jeff and Peter Marenghi answered a variety of questions ranging from metamorphic reactions to the current exploration strategy. Once on surface Noranda supplied a lunch for the hungry Chapter members.
Skarn mineralization seen at the C-zone
After lunch the participants were divided into two groups to tour the mill and smelter facilities. At the mill we saw how the ore was processed using rod and ball crushers, and separated by froth floatation. The capacity of the mill is 3000 tonnes per day. After drying, the concentrate is sent to the smelter. The copper concentrate that enters the smelter complex undergoes four phases of processing: fluid-bed roasting, reverberatory furnace, converters, and anode furnace. The converter process produces sulphuric acid as a by-product, as well as copper blister that is fed into the anode furnace to produce the copper anodes. The final stage of copper production is the refining of the anodes, which is done in East Montreal. Murdochville also smelts copper from Noranda's mines in Chile.
Froth floatation after the crushing process
Copper being poured after smelting
The final stage of the process at Murdochville; freshly poured copper anodes being cooled.
Thanks are extended to chief geologist Jeff Hussey who organized the mine tour, as well as Peter Marenghi, Pat Element, Denis Sylvain, Serge St-Pierre and Gilles Fortin, who all helped with the mine, mill, and smelter tours. There was general agreement among the Chapter members that this tour was one of the best any of them had participated in.
Participants of the trip were (back left to right): Alex Wills (Treas.), Alex Fitzpatrick, Katherine Ault, Sandy Archibald (Sec.), Jeff Hussey (mine geologist), Martin Heiligmann (Pres.), Mark Nelson, Jane Kwak, Zha-Zha Plandowski. Front row: Iain Chartrand, Annick Chouinard, Venetia Bodycomb, Sylvia Ramirez. Not present in photograph, David Mapp.
The McGill Chapter of the SEG would like to thank the following corporate members for sponsorship during 1998-1999:
Barrick Gold Corp.
Cominco Ltd.
Falconbridge Ltd.
INCO
Kinross Gold Corp.
Quebec Cartier Mining Company
and the following companies who provided financial assistance for the Latin America ore deposit trip:
Cominco Ltd.
INCO
Kinross Gold Corp.
Interested in becoming a sponsor?
Should your company wish to sponsor our student chapter, then as a thank you, we shall be pleased to advertise your logo on our website and in our future promotional efforts. For more information, please contact us.
