“Reduced” Porphyry Copper-Gold Deposits Issue 67

OCTOBER

2000

Issue 67

A model for the genesis of “reduced” porphyry copper-gold deposits

Stephen M. Rowins phyry Cu-Au deposits (RPCG) lack pri- Phanerozoic examples include San Anton The University of British Columbia mary hematite, magnetite, and sulfate min- (Mexico), Mamut (Malaysia), San Jorge Department of Earth & Ocean Sci- erals, but contain abundant hypogene pyr- (Argentina), and possibly Madeleine ences, 6339 Stores Road, Vancouver, rhotite, commonly have carbonic ore fluids (Quebec). The 17 Mile Hill Cu-Au deposit with substantial CH4, and are associated in western Australia has all the characteris- B.C., Canada V6T 1Z4 with ilmenite-bearing, reduced I-type tics of a Neoproterozoic RPCG system. [email protected] granitoids. Based on a synthesis of theo- Probable examples of late Archean RPCG retical, experimental, and field data, a deposits include the Boddington Cu-Au- Introduction variation on the classic porphyry Cu model Mo deposit in western Australia, and the In the magmatic-hydrothermal spectrum of is advanced to explain the formation of Clark Lake Cu-Mo-Au and Lac Tröilus ore deposits, the porphyry Cu (Mo-Au) RPCG deposits and their relatively Cu- Cu-Au deposits in northwestern Quebec class is probably the best understood. One poor, but Au-rich nature. It is proposed that (Table 2). Reduced porphyry Cu-Au de- of the fundamental tenets of the modern during fluid boiling or immiscible phase posits may also cluster into “districts” or porphyry Cu (Mo-Au) model is that ore separation, Cu, and especially Au, are “provinces”. Late Eocene porphyry Cu-Au fluids are relatively oxidized. Oxygen fu- transported largely via the vapor phase to deposits in the Battle Mountain area of gacities (ƒO2’s) typically range between distal sites up to several kilometres away north central Nevada (Copper Canyon, the nickel-nickel oxide (NNO) and the from the causative porphyry. This en- Elder Creek, and Upper Paiute Canyon) hematite-magnetite (HM) oxygen buffers hanced metal mobility in the vapor phase likely define one such district as do early at the appropriate temperatures of minerali- yields a low-grade Cu-Au core and the im- Mesozoic porphyry-style Cu-Au deposits zation (e.g., Burnham and Ohmoto, 1980). pression of a subeconomic or "failed" por- in the Pine Grove district of southwest Ne- Proof of this high ƒO2 comes from the phyry Cu system in many cases. In fact, vada (the Wheeler and Wilson mines). The abundant primary magnetite, hematite, and the low-grade Cu-Au core is an expected numerous “pyrrhotite porphyries” of the anhydrite in equilibrium with hypogene consequence of both fluid evolution in Tertiary Cascade Range porphyry Cu prov- Cu-Fe sulfide minerals (chalcopyrite, bor- RPCG deposits and the initial metal budget ince in Washington and Oregon (i.e., nite) and the association of porphyry Cu of the hydrothermal ore system. The recog- Quartz Creek and North Fork amongst oth- deposits with oxidized I-type or magnetite- nition of a RPCG system should prompt ers; Hollister, 1978) very likely constitute a series granitoids. In stark contrast to these the mineral explorationist to search at dis- RPCG province. highly oxidized fluid systems are a group tal sites deemed favorable for focussing The deposits described above were se- of porphyry Cu-Au deposits, ranging in and precipitating Au- and Cu-rich vapors. lected based on their recognition as “true” age from late Archean to late Miocene, that The proposed RPCG model does not con- porphyry Cu±Au deposits, albeit of the have formed from relatively reduced tradict the current understanding of por- newly defined RPCG subclass. There are hydrothermal fluids, i.e., ƒO2’s below the phyry Cu-Au formation. Rather, it adds yet other Au deposits, both with and without fayalite-magnetite-quartz (FMQ) oxygen another variation on the theme of porphyry clearly related Cu mineralization, whose buffer (Rowins et al., 1993; Rowins, 1999; Cu-Au genesis. origins are contentious, that may fit the Rowins, 2000a, b). These “reduced” por- RPCG subclass. These include Alaskan Examples of reduced porphyry copper- deposits in the “Tintina Gold Belt” such as ,QVLGH WKLV LVVXH gold deposits, districts, and provinces Liberty Bell and Shotgun. Both of these Reduced porphyry copper-gold deposits Au deposits display evidence of having 0HVVDJH IURP 3UHVLGHQW (Fig. 1) are identical to the classically oxi- formed from relatively reduced ore fluids dized variants except for the characteristics (e.g., abundant hypogene pyrrhotite and 0'' +LVWRU\ described above and listed in Table 1. The significant CH4 in mixed aqueous-carbonic )XWXUH 'LUHFWLRQV remarkably similar set of geological fea- fluid inclusions) and are genetically associ- tures developed in each RPCG deposit ated with reduced I-type granitoids (Table 0(5$ strongly supports the premise that they 2). In British Columbia, auriferous massive constitute a distinct subclass of porphyry- (Continued on page 4) 'DQ %R\OH IRQGO\ UHPHPEHUHG style Cu-Au mineralization (e.g., Table 2). 0,1(5$/ ''(326,(326,7766'',9,6,2,9,6,211 ((;(&87,9;(&87,9((/,/,6677 MDD Goals and Objectives

Chairperson: Andrew Conly The Gangue is published quarterly by the Min- Dept. of Geology, Univ. of Toronto, 22 Russell St. Toronto, ON M5S 3B1; Tel: eral Deposits Division of GAC and is distrib- (416) 978-0657; FAX: (416) 978-3938; email: [email protected] uted to its members. The Mineral Deposits Di- vision of the Geological Association of Canada Past Chairperson: Jason Dunning is Canada’s foremost society for promoting the Hudson Bay Exploration and Development Co. study of mineral deposits by supporting local 800-700 Pender St. W., Vancouver, BC V6C 1G8; and national meetings, symposia, short courses Tel: (604) 684-1454; FAX: (604) 689-3480; email: [email protected] and field trips. We sponsor the publication of research relating to ore deposits and metallog- Vice Chairperson: Stephan J. Piercey eny, and recognize the contributions of out- MDRU, Dept. of Earth & Ocean Sciences, University of British Columbia, 6339 standing Canadian economic geologists by an- Stores Rd., Vancouver, BC V6T 1Z4; Tel: (604) 822-6654; FAX: (604) 822-6088; nually awarding the Duncan Derry and Wil- email: [email protected] liam Harvey Gross medals and the Julian Boldy Certificate. Secretary: Gary S. Wells Inmet Mining Corporation, 1300 Blvd. Sagunay, Rouyn-Noranda, QC J9X 7C3; Publication Schedule: Tel: (819) 764-6666 ext. 223; Fax: (819) 764-6404; SUBMISSION DATE email: [email protected] December 15 January March 15 April Treasurer: Robert J. Cathro June 15 July Cathro Exploration Corp, RR#1, Site U-39, Bowen Is., BC, V0N 1G0; September 15 October Tel: (604) 947-0038; Fax: (604) 947-0038 or, Arizona, Tel/Fax: (602) 423-1006; email: [email protected] Information for contributors: The objective of this newsletter is primarily to Publications: Dirk Tempelman-Kluit provide a forum for members and other profes- 4697 West 4th St., Vancouver, BC; sionals to voice new ideas, describe interesting Tel/FAX: (604) 224-5582; Fax: (604) 224-6903; email: [email protected] mineral occurrences or expound on deposit models. Articles on ore deposits, deposit mod- Professional Development – Short Courses: Iain M. Samson els, news events, field trips, book reviews, con- Dept. of Earth Sciences, Univ. of Windsor, Windsor, ON N9B 3P4; ferences, reprints of presentations to compa- Tel: (519) 253-4232 ext 2489; FAX: (519) 973-7081; email: [email protected] nies, mining groups or conferences, or other material which may be of interest to the eco- Professional Development – Field Trips: Dani Alldrick nomic geology community are welcome. BC Geological Survey, 5 - 1810 Blanshard Street, Victoria, BC V8T 4J1; Manuscripts should be submitted by email in Tel: (250) 952-0412; Fax: (250) 952-0381; WP or WORD format. A printed version email: [email protected] should be mailed or FAXed. Illustrations should be camera-ready (ideally as CDR digi- Program Chair: GEOCANADA 2000: Michael Marchand tal files); photos should be of good qual- Madrona Mining Ltd., Calgary, AB; Tel/Fax: (403) 282-5105; ity. Short items dealing with news events or email: [email protected] meetings can be submitted by FAX, postal mail or email. Contributions may be edited for Medals Committee: Charlie Jefferson clarity or brevity. Geological Survey of Canada, 601 Booth St., Ottawa, ON K1A 0E8; Tel: (613) 996-4561; Fax: (613) 996-9820; email:[email protected] For Information & Submissions: David Lentz – THE GANGUE PLEASE CHECK OUT OUR Internet Website: Dept. of Geology, Univ. of New Brunswick, www.northfacesoftware.com/mdd Fredericton, NB E3B 5A3 Email: [email protected] Remember the time for nominations is NOW, Please Check our the GAC website and MDD Steven McCutcheon – THE GANGUE website for procedures on nominating worth N.B. Geological Survey, PO Box 50, 495 Riverside Drive, Bathurst, NB E2A 3Z1 candidates for the various medals and awards!!!! Email: [email protected]

October 2000 – Gangue No. 67 MDD DIRECTORS President’s Message

• Georges Beaudoin (2000-2003) I am pleased to announce the appointment of Dr. Georges Beaudoin (University of Dept. de geologie et de genie geologique, Laval), Dr. Mike Lesher (MERC – Laurentian University) and Dr. Tom Lane (Teck l’Universite Laval, Quebec City, QC; Tel: Exploration – Toronto) to the MDD Board of Directors. Their three-year term will (418) 656-3141; Fax: (418) 656-7339; email: end June 2003. I thank outgoing Directors Dr. Kevin Ansdell (University of Sas- [email protected] katchewan), Dr. Harold Gibson (MERC – Laurentian University) and Dr. Baxter Kean (Newfoundland Dept. of Mines and Energy) for the past three years of service • Mike Lesher (2000-2003) and wish them the best for the future. Dept. of Earth Sciences, MERC, Laurentian Other division news is that our two pending publications, the Latin American Univ., Sudbury, ON; Tel: (705) 675-1151 VMS and Sullivan volumes, are on-schedule for release early in the New Year. ext 2276; Fax: (705) 673-6508; email: Both volumes will be a great addition to everyone’s bookshelf. To ensure that our [email protected] proposed Structural Atlas, a joint project with the Structural and Tectonics Division, is successful the editors require submissions from the general membership of both • Tom Lane (2000-2003) divisions. This is of key importance for our members in order to guarantee that the Teck Exploration Ltd., Toronto, ON; Tel: volume has a strong ore deposits content. Those wishing to contribute photographs (416) 862-7102 ext 220; Fax: (416) 365- (or slides) with a brief description should contract Prof. Sandy Cruden, Senior Edi- 7747; email: [email protected] tor, at the University of Toronto (Tel: 416-946-7284; Fax: 416-978-3938; Email: [email protected]). • Dan Marshall (1999-2002) Over the fall we have confirmed on our involvement in two major conferences: Dept. of Earth Sciences, Simon Fraser Univ., 1) The MDD is now an official co-sponsors, along with the Newfoundland Dept. of Vancouver, BC; Tel: (604) 291-5474; Fax: Mines and Energy and Irish Geological Survey, for the North Atlantic Mineral Sym- (604) 291-4198; email: [email protected] posium (NAMS), held during GAC-MAC in St. John’s. NAMS will be the main economic session at GAC-MAC, thus it is imperative that the MDD participates. • Dave Peck (1999-2002) Specifically, the MDD will be providing travel grants for two speakers for the Falconbridge Exploration Ltd. break-away session on the Geology of North Atlantic Mineral Deposits. 2) Probably 21C Murray Park Road, Winnipeg, MB; the single most important event for MDD members will be the NUNA conference Tel.: (204) 888-9860; Fax: (204) 885-4152; on Direction of Mineral Deposit and Metallogenic Research in Canada. Over the Email: [email protected] past decade the mineral deposits community has seen a decrease in the amount of research funding, resulting from a shift in NSERC funding away from geoscience, a • lack of government funding for geological surveys, and a decline in industry interest Jeremy Richards (1999-2002) in funding research. The purpose of this conference is: a) to educate the various Dept. of Earth Sciences, Univ. of Alberta, funding agencies on the importance of mineral deposit research; and b) to build a Edmonton, AB; Tel: (403) 492-3430; Fax: consensus on the future direction of mineral deposits research and develop a strat- (403) 492-2030; email: Jeremy Rich- egy to achieve an enhanced mineral deposits research program. Conference partici- [email protected] pation will be by invitation only, and consist of an open forum, followed by concur- • Derek Wilton (1999-2002) rent sessions/workshops to address the main issues raised at the meeting. Specific goals of the break-out sessions include: 1) developing a strategy for a network of Dept. of Earth Sciences, Memorial Univ. of key mineral research centres; 2) assessing the role of the Canadian Mining Industry Nfld., St. John’s, NF; Tel: (709) 737-8389; Research Organization and similar organizations in channelling future research Fax: (709) 737-2589;email: dwilton@kean. funding; 3) proposing ways to better integrate government and academic research; ucs.mun.ca 4) identifying priority areas for research funding, including enabling technologies • and facilities, and suggesting strategies to achieve this vision. Invited speakers Bob Friesen (1998-2001) would come from both the funding agencies and the research community, including Teck Exploration, Kamloops, BC; Tel: (250) invited participation from other countries and organizations with past experience in 372-0032; Fax: (250) 372-1285; developing national strategies for mineral deposits research. The conference is email: [email protected] scheduled for March 15 and 16, 2001, following the PDAC convention, at Queen’s University. The MDD has agreed to co-sponsor the meeting due to the critical im- • Mike Sweeney (1998-2001) portance it has for our membership. And as a co-sponsor the MDD will have repre- Falconbridge Exploration, Falconbridge, sentation at the conference. ON; Tel: (705) 693-2761 ext. 3655; Fax: In closing, with the holiday season soon upon us, I wish that all members have a (705) 699-3600; email: happy holiday and prosperous New Year. [email protected] Sincerely,

Andrew G. Conly—MDD Chairman, 2000-2001 October 2000 – Gangue No. 67 3 (Continued from page 1) remains the dominant S species. In contrast, under the high ƒO2 pyrrhotite-chalcopyrite veins in the historic Rossland Au camp conditions more typical of porphyry Cu deposits, Cu and Fe ap- bear all the hallmarks of distal Au (Cu) veins associated with a parently exhibit comparable solubilites. Similar experimental re- large RPCG system. sults of decreasing Cu solubility with decreasing ƒO2 in dilute aqueous fluids at elevated temperatures and pressures were ob- Copper and gold transport in the porphyry environment tained by Seyfried and Ding (1993). In view of the critical importance that fluid oxidation state is pro- Unlike Cu, however, dissolved Au (>0.1 ppm) as AuCl2-, is posed to play in the formation of RPCG deposits, the solubility of transported in similar quantities in magmatic brines regardless of Cu and Au in both oxidized and reduced hydrothermal fluids, at the oxidation state of the system (Gammons and Williams-Jones, PTX conditions approximating those of the porphyry environ- 1997). For example, at 500°C, Au solubilities are only ~1.1 log ment, needs to be assessed for compatibility with the RPCG units apart for a strongly oxidized fluid (at the SO2/H2S buffer) model. The partitioning of metals into coeval vapor and liquid versus a strongly reduced fluid (at the CO2/CH4 buffer - see Fig- brine phases during fluid immiscibility, and the oxidation state of ure 5 in Gammons and Williams-Jones, 1997). The recent experi- related felsic porphyries, also must be considered in the construc- mental studies of Loucks and Mavrogenes (1999) also support tion of the RPCG model. this conclusion, but they proposed Au transport as a hydrosulfide complex under these conditions. Taken together, these metal solubility studies indicate that Oxidized ore fluids (the “classic” porphyry Cu-Au model) significant quantities of Au can be transported by hot, saline, Experimental, thermodynamic, and fluid inclusion studies magmatic fluids under either reducing or oxidizing conditions, strongly suggest that Cu in potassic alteration zones is transported whereas Cu transport is much more favored in the oxidizing envi- as an aqueous chloride complex (CuCl°) in high-temperature ronment. Thus, RPCG ore systems have the potential to transport ~NNO to HM buffer), (350° to >700°C), relatively oxidized (ƒO2 just as much Au as the classically oxidized porphyry systems, but hydrothermal brines (e.g., Burnham and Ohmoto, 1980; Hemley significantly less Cu. The relatively Cu-poor nature of the RPCG et al., 1992). Brines are produced mainly (but not always) by deposits in Table 2 compared to oxidized equivalents supports aqueous fluid immiscibility at high-temperatures (e.g., Burnham this conclusion. and Ohmoto, 1980). Gold transport in the oxidized porphyry environment is more complicated as thermodynamic calculations Fluid immiscibility (boiling) and gold-copper partitioning indicate a switchover from a chloride complex (AuCl -) to a more 2 Although experimental metal solubility studies of porphyry Cu soluble bisulfide complex [Au(HS) -] with cooling of the ore flu- 2 systems have demonstrated repeatedly that Cu and Au partition ids (Gammons and Williams-Jones, 1997). The temperature of into the saline aqueous brine during immiscible phase separation the chloride-bisulfide transition, typically ranging from 350° to of oxidized high-temperature fluids (e.g., Williams et al., 1995, 460°C, depends on the pH and H S/Cl ratio of the original fluid 2 and references therein), there are new microanalytical data that and whether or not immiscibility occurs. The change of transport- suggest the opposite occurs if ore fluids are reduced. Proton- ing ligand for Au provides a reasonable explanation for the distal induced X-ray emission (PIXE) and laser-ablation inductively position of Au-rich zones in some classically oxidized porphyry coupled plasma mass spectrometry (LA-ICP-MS) studies of fluid Cu deposits. inclusions from reduced Sn-W-Ag porphyry deposits and por-

phyry-related Au-Mo breccias, reveal that Cu, and very likely Reduced ore fluids (the RPCG model) Au, strongly partition into the low density H2S-rich vapor phase Experimental and thermodynamic data on Cu and Au solubilities rather than the co-existing high density chloride-rich liquid dur- ’s (£ in high-temperature aqueous fluids at relatively low ƒO2 ing moderately high pressure phase separation (e.g., Heinrich et CO /CH buffer) are less common than for high ƒO ’s, i.e., the 2 4 2 al., 1999, and references therein). These studies also indicate that typical porphyry Cu environment. Experiments by Hemley et al. significant Cu and Au can partition into the vapor phase in some (1992) reveal that moderately saline (5 wt.% NaCl), relatively oxidized porphyry Cu deposits (e.g., Grasberg), although the ten- reduced, single phase (non-boiling), hydrothermal fluids at 300° dency is considerably less than for reduced systems. Although the to 700°C and 0.5 to 2 kbars can transport modest quantities of Cu precise partition mechanism remains unclear, this vapor transport (typically 10’s to 100’s of ppm) as neutral chloride species. These of Au and Cu directly impacts on how metals will be zoned in same experiments also show that the solubility of Cu is one to reduced porphyry ore systems. Specifically, Au in reduced H2S- two orders of magnitude lower than that of Fe, Zn, or Pb. Copper rich magmatic vapors will tend to be carried away from the par- solubility does increase with higher chloride concentrations and ent intrusion, since lower ƒS2, but changes little with ƒO2 provided that reduced S Table 1. Distinguishing features of RPCG deposits • Pyrrhotite-rich hypogene ore assemblage (massive pyrrhotite veins very common) • No primary magnetite, hematite, or sulphate minerals (e.g., anhydrite)

• Ore fluids commonly CO2-bearing with a significant CH4 component • Mineralization associated with ilmenite-bearing, reduced I-type granitoids • Relatively low grades of Cu and Au in potassic and/or phyllic alteration zones are common

October 2000 – Gangue No. 67 Deposit District Province

Figure 1 – Location map for reduced porphyry Cu-Au deposits, districts, and provinces. Details are listed in Table 2. Deposit num- bers are as follows: (1) 17 Mile Hill; (2) Boddington; (3) Mamut; (4) San Jorge; (5) San Anton; (6) Battle Mountain district (Copper Canyon, Elder Creek, Upper Paiute Canyon); (7) Pine Grove district (Wheeler, Wilson); (8) Cascade province (Quartz Creek, Middle Fork); (9) Rossland; (10) Madeleine; (11) Clark lake; (12) Lac Tröilus; (13) Shotgun; (14) Liberty Bell. not only does the vapor phase have a much higher diffusivity than Summary and conclusions the saline brine, but Au also, apparently, exhibits retrograde solu- Field studies prove the existence of RPCG deposits. This obser- bility with cooling to ~350°C in the vapor phase (Gammons and vation together with the recent thermodynamic and experimental Williams-Jones, 1997). studies documenting relatively high Au solubility in reduced saline fluids, coupled with the vapor transport of Au and Cu during subsequent fluid immiscibility, raises the possibility that reduced The oxidation state of felsic magmas and ore fluids in a boiling porphyry environment can, under favorable their gold-bearing potential circumstances, transport large quantities of Au (and Cu) as re- Field evidence and low fluid oxidation states suggest that RPCG duced S complexes to distal sites far from the causative porphyry. deposits are intimately associated with reduced I-type granitoids Mineralization in this peripheral environment may take several (Table 2). Low ƒO2 S-type granitoids also exsolve reduced hydro- forms, including structurally controlled, sheeted sulfide veins in thermal fluids, but these magmas are unlikely to be a factor in the hornfels and sulfide replacement bodies (mantos) in calcareous genesis of RPCG deposits for several reasons. As pointed out by metasedimentary rocks. Not surprisingly, the origin of some de- Burnham and Ohmoto (1980), S-type magmas, only contain posits described in this paper as likely RPCG deposits (Table 2) about 10% of the S present in I-type granitoids, and are partial have been the subject of considerable controversy, largely be- melts of metasedimentary sources containing much lower initial cause the gold mineralization could not be easily categorized as abundances of Cu and Au. Thus, S-type granitoids contain neither either porphyry-type (i.e., ores are pyrrhotite-rich) or mesother- sufficient S nor background metal concentrations to produce eco- mal vein-type (i.e., ores are proximal to porphyry systems). The nomic porphyry Cu-Au mineralization. proposed model redresses that situation and provides a flexible framework for their incorporation into a single genetic subclass

October 2000 – Gangue No. 67 5 Table 2. Selected characteristics of some RPCG deposits

Name, Location, Age Associated intrusions Mineralization style Hypogene alteration Ore fluid P-T-X 17 Mile Hill, Ilm-bearing, reduced I- Vn stwks; Sx frac Potassic, phyllic, pro- ~2 kb; 142-611oC; Western Australia, Neo- type monzogranite fillings & diss; mass. pylitic, argillic, H2O-NaCl-CO2-CH4 proterozoic (~650 Ma) Po vns sideritic San Anton, Mexico Ilm-bearing, reduced I- Vn stwks; Sx frac Potassic, phyllic, pro- <0.5 kb; Oligocene (24-38 Ma) type (?) Qtz monzonite fillings & diss; mass pylitic, argillic, 174 to >560oC; Po vns; epithermal Au sideritic H2O-NaCl (CO2-CH4)

o Mamut, Malaysia Hbl-Bt monzogranite Sheeted Qtz-Sx vns; Potassic, phyllic, 280-450 C; H2O-NaCl Late Miocene (9 Ma) (adamellite) porphyry Qtz-Sx vn stwks & Silicic; local propylitic diss (Ep-Chl-Cal)

San Jorge, Argentina Granodiorite porphyry Vn stwks; Sx frac Potassic, phyllic, Early Permian (260 Ma) fillings & diss; Silicic; weak propylitic Qtz-Sx bx

Madeleine, Quebec, Canada Ilm & Mag-bearing, per- Plunging Qtz-Sx vn Potassic, calc-silicate 1-2 kb; 400-600oC; Devonian (~370 Ma) alum granitoids to peralk stwk orebodies (Act-Ep), Chl-Ms H2O-NaCl-CO2-CH4 syenites

Copper Canyon, Nevada, USA Reduced I-type (?) grano- Vn stwks; Repl. Sx in Potassic, phyllic, calc- ~0.5 kb; 250-375oC; Eocene (38-39 Ma) diorite porphyry tabular lenses; Au silicate skarn H2O-NaCl-CO2-CH4 skarn Upper Paiute Canyon, Nevada, USA Bt-Hbl monzogranite por- Vn stwks; Repl. Sx in Potassic, v. local pro- Eocene (38-40 Ma) phyry tabular lenses; Qtz-Au pylitic, phyllic, argillic vns Elder Creek, Bt-Hbl monzogranite por- Vn stwks Potassic, propylitic, v. ~1kb?; 350-550oC; Nevada, USA phyry weak phyllic H2O-NaCl Eocene (38 Ma) Wheeler & Wilson mines, Ilm & Mag-bearing, Hbl- Au-bearing Qtz-Sx Potassic, sodic, phyllic 2-3 kb; 300-500oC Nevada, USA, Early Bt granodiorite vns; Mass Sx vns (Py- (Ser-Qtz); minor Chl H2O-NaCl (CO2-CH4?) Mesozoic (187-233 Ma) Ccp-Po-Mag) Quartz Creek, Hbl-Bt Qtz diorite & Sx bx pipes; Qtz-Sx Potassic; local phyllic Washington, USA granodiorite vns & diss; mass Sx (Qtz-Ser) & Chl assoc. Miocene (18-25 Ma) (Py-Po-Ccp) lenses with Bx pipes Middle Fork, Hbl-Bt Qtz diorite & Qtz-Sx bx & vns in en Potassic; local phyllic 0.5-1.5kb; <500oC Washington, USA granodiorite echelon shear zones; (Qtz-Ser-Ank-Sd) Miocene (18 Ma) Sx frac fillings & diss Rossland, B.C., Canada Mag-bearing Hbl-Bt mon- Parallel, tabular, cy- Silicic (Qtz) & pro- ~2 kb?;~400oC Early Jurassic (~190 Ma) zodiorite & augite por- moid vns of mass Po- pylitic phyry Py-Qtz (Cal-Ank-Sd-Chl) Liberty Bell, Alaska, USA Ilm-bearing, reduced I- Repl. Sx in tabular Potassic, phyllic (Qtz- 0.25-0.83 kb; Late Cretaceous (~92 Ma) type Qtz-Fsp granite por- lenses & stringers; Ser-Clay), chloritic 350-450oC; phyry mass Po vns (Chl-Ser-Cal) H2O-NaCl-CO2-CH4 Shotgun, Alaska, USA Late Cretaceous (70 Reduced I-type (?) granite Vn stwks; Sx frac & Albitic, phyllic (Ser- 0.5 kb; 350-600oC; Ma) porphyry diss; Sx bx Qtz), carbonate H2O-NaCl-CO2-CH4 Boddington, W. Australia I-type? Diorite to Qtz dio- Stwk Qtz-Sx vns; Potassic, phyllic, pro- >1 kb; 200-440oC; Late Archean (2650+/-50 Ma) rite Qtz-native Au vns pylitic, calc-silicate H2O-CaCl2-NaCl-CH4 Clark Lake, Quebec, Canada Reduced I-type (?) tonalite Vn stwks; Sx frac Phyllic & propylitic ~0.8 kb; 130-430oC; Late Archean (2715 Ma) porphyry fillings & diss; mass CaCl2-NaCl-H2O-CH4 Po vns Lac Tröilus, Quebec, Canada Ilm-bearing, reduced I- Vn stwks; Sx frac Potassic, phyllic, pro- <1 kb; 250-600oC? Late Archean (~2700 Ma) type (?) Qtz-Fsp granite fillings & diss; semi- pylitic H2O-CaCl2-NaCl-CH4? porphyry mass Sx vns Note: Tectonic setting of all deposits is 'convergent plate margin'; Key references for each deposit are given in Rowins (2000a); Abbreviations are as follows: Act=actinolite, Ank=ankerite, Bt=biotite, bx=breccia, Cal=calcite, Ccp=chalcopyrite, Chl=chlorite, diss=disseminations, Ep=epidote, frac=fractures, Fsp=feldspar, Hbl=hornblende, Ilm=ilmenite, Ksp=K-feldspar, Ma=million years, Mag=magnetite, mass=massive, Ms=muscovite, peralum=peraluminous, peralk=peralkaline, Po=pyrrhotite, Py=pyrite, Qtz=quartz, repl.=replacement, stwks=stockworks, sx=sulphide, Sd=siderite, Ser=sericite, vn=vein. October 2000 – Gangue No. 67 of porphyry-style Cu-Au mineralization. Hill porphyry copper-style deposit, Telfer District, Western Australia: 2nd National Meeting of the Specialist Group in References Economic Geology, Geological Society of Australia Ab- Burnham, C.W., and Ohmoto, H., 1980. Late-stage processes in stracts, v. 34, p. 68-70. felsic magmatism:.Mining Geology Special Issue, No. 8, p. Rowins, S.M., 1999. Reduced porphyry copper-gold deposits: A 1-11. newly recognized style of gold mineralization. Geological Gammons, C.H., & Williams-Jones, A.E., 1997. Chemical mobil- Society of America Abstracts with Program, v. 31, No. 7, ity of gold in the porphyry-epithermal environment. Eco- A92. nomic Geology, v. 92, p. 45-59. Rowins, S.M., 2000a. Reduced porphyry copper-gold deposits: A Hemley, J.J., Cygan, G.L., Fein, J.B., Robinson, G.R., & D’An- new variation on an old theme: Geology, v. 28, p. 491-494 gelo, W.M., 1992. Hydrothermal ore-forming processes in Rowins, S.M., Wong, V., Flores, R., Camacho, S., & Lopez, J., the light of studies in rock-buffered systems: I. Fe-Cu-Zn-Pb 2000b. The link between mid-Tertiary epithermal Ag-Au sulphide solubility relations. Economic Geology, v. 87, p. 1- veins and reduced porphyry Cu-Au (Ag-Pb-Zn) mineraliza- 22. tion at the San Anton deposit, Guanajuato, Mexico: Geologi- Heinrich, C.A., Günther, D., Audétat, A., Ulrich, T., & cal Society of America Abstracts with Program, v. 32, p.xx. Frischknecht, R., 1999. Metal fractionation between mag- Seyfried, W.E., Jr., & Ding, K., 1993. The effect of redox on the matic brine and vapor, determined by microanalysis of fluid relative solubilities of copper and iron in Cl-bearing aqueous inclusions. Geology, v. 27, p. 755-758. fluids at elevated temperatues and pressures: an experimental Hollister, V.F., 1978. Geology of the porphyry copper deposits of study with application to subseafloor hydrothermal systems. the western hemisphere. Society of Mining Engineers of Geochimica et Cosmochimica Acta, v. 57, p. 1905-1917. AIME, 219 p. Williams, T.J., Candela, P.A., & Piccoli, P.M., 1995. The parti- Loucks, R.R., & Mavrogenes, J.A., 1999. Gold solubility in su- tioning of copper between silicate melts and two-phase aque- percritical hydrothermal brines measured in synthetic fluid ous fluids: an experimental investigation at 1 kbar, 800°C, inclusions. Science, v. 284, p. 2159-2163. and 0.5 kbar, 850°C. Contributions to Mineralogy and Pe- Rowins, S.M., Groves, D.I., McNaughton, N.J., Brown, P.E., trology, v. 121, p. 388-399. McLeod, R.L., & Hall, D., 1993. Evidence of unusually carbonic and reduced ore fluids in the Late Proterozoic 17 Mile Editors Note: This is a Boldy Award contribution.

The Art & Science of Writing Geoscience Reports by Brian Grant, P.Geo. (ISBN 0-9687693-0-6)

This new reference manual should be a part of every geologist's library. It: • identifies & describes topics required for comprehensive geological reports, • provides standards for the contents of geoscience reports and maps, • recommends style and presentation concepts, • recommends appropriate usage for common geoscience language, • incorporates standards for data acquisition and presentation, • provides guidelines for editing and review of reports, • includes numerous illustrations and handy tables with reference information, • includes a newly revised geological time scale. This publication is of broad interest to geoscientists regardless of specialty, and is a valuable reference for mineral exploration geologists, government researchers and students. Since its initial printing in late 1999 it has been sold to professionals on every continent, and is now widely used by industry, government and university organizations. It has received numerous favourable reviews. This manual focuses on how to generate comprehensive geoscience reports, and provides the standards required for consistency. It also identifies the basic elements required to ensure data credibility and accuracy in interpretation. In addition, the manual provides a basis for evaluating and understanding geoscience reports and data by those regulators, stock brokers, company directors, analysts and investment managers who specialize in minerals related activities. The first part of the manual describes essential components of a report and the type of detailed information required to adequately cover various geoscience topics. It presents techniques for reviewing and editing scientific information, and establishes a basis for evaluating published reports on mineral properties and other research. It provides standards for geoscience report & map content and layout, standard geological symbols, provides basic grammar and language concepts of interest to geoscientists, and presents appropriate usage for scientific terms. The manual incorporates and elaborates on recommendations for reporting proposed in the new Canadian National Standards 43-101 produced by the Toronto Stock Exchange and the Ontario Securities Commission. Purchasing Information: This 200-page, plasticized & spiral bound, 6x9 inch format, colour manual is distributed by the Prospectors and Devel- opers Association of Canada. It is available for $55 Cdn, and purchasing details can be obtained from the publications section of the Prospectors and Developers Association of Canada (PDAC) website: www.pdac.ca E-mail: [email protected] For a complete and detailed table of contents, visit the website at: http://sites.netscape.net/geomanual

October 2000 – Gangue No. 67 1985 MDD JAPAN FIELD TRIP - NONTECHNICAL MDD HISTORY MEMORIES

This is the first of a series of articles that will appear from time to It all started in the Nevada desert in October 1983. Yours time in the months leading up to the 25th anniversary of the Min- truly was one of 46 appreciative participants on the MDD eral Deposits Division in 2003. This story focuses attention on Nevada epithermal Au-Ag deposits field trip organized by the role played by the first Officers, Directors, and organizers of the late great Bob Hewton. In those days Bob and I served on field trips and conferences in raising the seed money that became the MDD executive council. We were keenly aware that our the foundation of our current financial strength. The trip to Japan mandate to encourage and financially support publication of in April 1985, described here, has the distinction of being the best mineral deposits research relied upon seed funding from a managed (most overbudgeted ?) trip in the history of the division, very modest bank account. To this point in time publication and was only exceeded in financial importance by the Gold 86 sales, conference receipts and interest had been our primary conference in Toronto. It is hard to imagine today that an ex- sources of revenue. However, following the enthusiastic re- tremely successful trip to Japan could be mounted for only $2500 sponse to the Nevada tour it was clear that field trips could per head and still produce a surplus of almost $500 each. Those make an important contribution. To keep the till full we were truly the 'good old days', when the industry was strong, ex- needed another field trip. It was my turn. pense accounts were generous, and the Canadian dollar was worth something. (Jeff estimates that a similar trip today would cost In the early 1980’s epithermal Au-Ag and volcanogenic mas- $C10,000.) sive sulphide deposits were the darlings of the Cordilleran In addition to the author of this article, particular mention exploration community. Names such as Gold Quarry, Jerritt should be made of Ron McMillan, Bob Hewton, Paul Wodjak, Canyon, El Indio, Greens Creek, HW and Windy Craggy Alex Davidson, Ian Patterson, Ken Dawson, Ray Goldie and readily come to mind. In order to launch a successful field Terry Botterill, all of whom appear in the musty financial files as trip we needed deposits of a similar ilk in a field trip having played leading roles in our most profitable trips and con- ‘friendly’ place. In my mind that place was Japan. The first ferences. If I have missed anyone, it is because the files are in- calls went to Steve Scott and Al Sinclair. Steve had recently complete. Please accept our apologies and write us with your completed a sabbatical in Japan and Al - in his capacity as memories to complete the record. Special recognition is due to MDD Treasurer - was keeper of the purse. Steve and Tetsuro our first Treasurer, Al Sinclair, who served for over 10 years and Urabe, with the support of the Society of Mining Geologists set us on a sensible course. of Japan, agreed to organize mine visits and lead the tour. Al and I discussed the financial risks and rewards and decided Bob Cathro that with an appropriate contingency fund, over and above a reasonable profit margin, it was doable. And so it began.

Some 18 months later on April 13, 1985, 30 eager participants - each paying $C2500 - assembled at Vancouver International airport. Our two week bus and train tour would begin at the subtropical southernmost island of Kyushu and follow the blossoming cherry trees north for 1500 km to the more temperate northern tip of Honshu. However, prior to leaving Vancouver some housekeeping was in order. I had been advised that our Japanese hosts had a particular interest in Canadian whiskey. Accordingly, 24 boxed presentation bottles of Alberta sipping whiskey were carefully distributed amongst the group’s luggage. After receiving solemn assurances that they would be returned upon request, unopened, we were on our way.

The trip had been billed as ‘all-inclusive’ from Vancouver. For a group of geologists, that meant everything except alcohol. With our arrival in Japan, currency exchange risk - as I recall about ¥275 to the Canadian dollar - was now behind us. In addition, our Japanese travel arrangements were being delivered with flawless reliability. The contingency fund was now redundant. What to do with a field trip that was making too much money? I was left with two options. Go home with an embarrassment of riches or convert the contingency fund into an alcohol fund. In life we are sometimes called upon to make difficult decisions. I choose the second op- tion.

One of our first stops on Kyushu was the recently opened Hishikari Au-Ag mine. This low sulphide quartz vein deposit is in an active geothermal system and at the time of our visit had reserves of 1.5Mtonnes grading 80 g Au/t and 40 g Ag/t. In lieu of an underground tour, the mine manager gave a comprehensive presentation on the geology of this small but magnificent deposit. He ex- plained that the high-grade Au-Ag ore was shipped directly to the nearby Sumitomo smelter, where it also provided silica flux for the smelting process. He then went on to say with typical Japanese understatement “after discovery of deposit decision made to proceed with great urgency. Feasibility study not required.” The late Murray Pezim couldn’t have promoted it better. Carefully labeled and packaged ore samples at ambient mine temperature (65ºC) were then presented to each member of the tour. A real class act.

After day visits to the Iwato gold mine, the then active Sakurajima volcano and a wonderful stay at the Ibuski Kanko resort hotel, we left Kyushu and traveled by overnight train to Himeji, home of Japan’s finest medieval castle. This was a very educational evening.

October 2000 – Gangue No. 67 We were introduced to Japanese train toilets (from the upright position, hold on tight, be steady, have strong thighs and aim well), devoured raw sea urchin eggs and witnessed first hand the prodigious Japanese taste for Alberta sipping whiskey. Yes, we had some contingency bottles. And yes again, the word ‘sipping’ is a misnomer. To the horror of the Japanese passengers, we lived up to our reputation as yabanjin or barbarians and, in the morning, literally ‘poured’ off the train at Himeji station. Almost everyone in the group had disembarked when our most senior member ‘lost’ his wallet. There was a mad scramble. In samurai-like fashion, rock hammers were quickly withdrawn from backpacks and jammed between the train doors. A search party ‘poured’ back onto the train, which was now behind schedule. In a vain attempt to get the train moving the conductor frantically blew his whistle and tried to re- move the hammers. He was pushed aside. Magically the ‘lost’ wallet reappeared in the ‘white-haired one’s’ back pocket, hammers returned to backpacks and the train left the station a little late but much more peaceful.

Over the next week we continued to work our way north with visits to the Yanahara (Cu), Akenobe (Cu, Zn, Sn) and Kamioka (Zn, Pb, Ag) mines and a day of sightseeing in Kyoto. Ohdate, at the northern tip of Honshu, was the final tour stop. Following hot and humid underground tours of the kuroko-type Shakanai and Matsumine mines, we retired to the hot baths at the Ohyu ryokan to per- form our now ritual ablutions. We had truly become Japanese! Resplendent in yakata robes we spent this final evening together in a traditional dining hiroma and enjoyed the finest in Japanese food, beverage and geisha entertainment. To bring the banquet to an unforgettable close, we performed the traditional Miner’s Dance (a confused mélange of preying mantis-like movements with imaginary picks and shovels) to the polite amusement of our geisha entertainers.

The next morning we boarded the legendary Shikansen train and left the beauty and relative calm of the Japanese countryside for the bright lights of Tokyo. Following an evening reception at the Canadian Embassy, we dispersed into smaller groups to explore downtown Tokyo. It was Friday evening, the traffic was unbelievable and there were sunaku bars everywhere. Two intrepid members of the group spent the good part of the evening at one such bar completely unaware of the financial consequences of doing so. After sipping a couple of beers, munching on some dried seaweed and having their legs rubbed (which they vehemently denied) their very attentive and attractive hostess mamasan presented them with a bill for $400. After some fairly tense moments with the sumo-like bartender, these citizens of the world escaped $150 poorer!

And so our wonderful trip ended. Steve and Tetsuro did an outstanding job in introducing 30 appreciative geologists to the mineral deposits and culture of Japan, I was able to deliver a cheque to Al Sinclair for $14,549 and yes, we still had a few dollars in the contingency fund. J.P. Franzen, West Vancouver, B.C

MDRU—UBC Department of Earth and Ocean Sciences Collaboration

Short Course 32 - Volcanism in Ore Genesis

Presented by: Jocelyn McPhie (University of Tasmania) and Raymond Cas (University of Monash)

The course, presented by two of the world's foremost experts, examines volcanic successions that host a variety of ore deposits. Understanding the processes and products of subaerial and submarine effusive and explosive eruptions, sedimentation I volcanic environments, and how that understanding can assist an exploration program is the central theme of the course. Emphasis will be placed on the volcanic successions that host massive sulfides, porphyry Cu-Au deposits, and epithermal Au-Ag deposits.

21-22 January, 2001, Sunday & Monday British Columbia Institute of Technology Downtown Campus, Vancouver, BC Please Contact: Dick Tosdal MDRU Member: CDN$ 250; Tel: (604) 822-5149 Early Registration: CDN$ 300 (until December 23, 2000) FAX: (604) 822-6088 Late Registration: CDN$ 350 (until January 19, 2001) Email: [email protected] Onsite Registration: CDN$ 425 Www.eos.ubc.ca/mdru Student: CDN$ 50

October 2000 – Gangue No. 67 A Geological Association of Canada Nuna Research Conference on

FUTURE DIRECTIONS FOR CANADIAN MINERAL DEPOSIT & METALLOGENIC RESEARCH Donald Gordon Conference Centre, Kingston, Ontario March 15-16, 2001

Organizers: Al Galley—coordinator (GSC), Jeremy Richards (U. of Alberta), Mark Hannington (GSC), Tom Lane (Teck Exploration)

A conference on FUTURE DIRECTIONS FOR CANADIAN MINERAL DEPOSIT AND METALLOGENIC RESEARCH will be held March 15-16, 2001 at the Donald Gordon Conference Centre in Kingston Ontario directly following the Prospectors and Developers Association of Canada (PDAC) annual meeting. The workshop will focus on evaluating the way mineral deposit research is carried out by Canadian institutions, and how we can better organize into an integrated research community that will be recognized by funding agencies as an important component of both geoscience and the global minerals industry. This conference will bring together the leading experts in mineral deposit research from academia, government and industry along with representatives of leading funding agencies from Canada, Australia and the United States. GAC NUNA Research Conferences are workshops of small size designed to advance key geoscience topics. The word “Nuna” means “the earth around us” in Inuktitut.

This two-day conference will include a series of invited overviews from representatives of various successful research groups and funding agencies, followed by a series of workshops on selected themes, and finally a plenary session to discuss group findings. Accommodation will be available for up to 55 participants at the Donald Gordon Conference Centre, allowing for ongoing discussion and exchange of ideas for the two evenings of the conference.

Major themes to be discussed may include:

1) Developing a strategy for networking mineral research centres 2) Assessing the role of CAMIRO and similar organizations in channeling future research funding 3) Proposing ways to better integrate government and academic research 4) Identifying new and priority areas for collaborative research

The results of the conference will be published by the GAC as a formal position paper for submission to government, academia and industry as a strategy for future mineral deposit and metallogenic research in Canada.

Dates for the conference were selected in order for participants to first attend the annual PDAC meeting in Toronto, followed by a short train or car ride to Kingston. The aim of the conference committee is to extend free registration to those who attend, although final funding arrangements are not yet in place. The committee extends to all interested persons an invitation to apply for conference attendance by Janu- ary 1, 2001. Please notify Alan Galley by email or fax. Alan Galley (convenor), Geological Survey of Canada, 601 Booth St., Ottawa, ON K1A 0E8; Tel: 613.992.7867; Fax: 613.996.9820; Email: [email protected]

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)RU JUHDW SXEOLFDWLRQV &+(&.287 : GAC’s website - http://www.gac.ca & MAC’s website -http://www.mineralogicalassociation.ca

October 2000 – Gangue No. 67 The History of Mineral and Energy Resource Assessment (MERA)

by Jack Patterson

Bismarck once said that there are two things you shouldn’t watch being made – sausages and legislation. We like to think that our laws result from careful analysis, thorough debate, statesmanship, and fairness. Although that may sometimes occur, legislation often suffers from partisan wrangling and narrow self-interest. The early years of the Trudeau government were a time of great opportunity for Parks Canada in the northern territories. The absence of opposition from provincial governments made it very easy to establish new National Parks. In short order, Kluane Park was created in Yukon and Nahanni Park followed in the NWT. As well, many others were proposed for active study (i.e. East Arm of Great Slave Lake). The mining industry repeatedly stated its support for the concept of expanding the network of National Parks but had coupled this support with concerns that mineral potential was not being given enough consideration in the process of deciding where to locate new parks. Nevertheless, Parks Canada was not about to give up its advantage. This is the story of how balance was restored, in the form of MERA, through quiet work by officials behind the scenes. For a period of time, including 1979, Parks Canada was a part of the Department of Indian Affairs and Northern De- velopment, a ministry trying to downplay its development role by calling itself Indian and Northern Affairs. At that time, Hugh Faulkner was the Minister and I was Chief, Mining Division, Northern Non-Renewable Resources Branch. One day in early 1979, I received a phone call from a colleague in the Department of Finance (who must remain name- less) informing me that Parks Canada would be presenting its new policy to a Cabinet Committee the following day. The new Parks policy document would not contain any explicit requirement for non-renewable assessments of proposed parks. We quickly reviewed our previous discussions on this topic, in which we agreed that proposed parks should re- ceive, as a minimum assessment, geological mapping, geochemical sampling and geophysical surveys. We decided that we would both make every effort to place the assessment concept in front of Ministers for review. I immediately phoned Gordon ‘Jeff’ Jeffery at Energy, Mines & Resources, relating my conversation with Finance, and asked him to see if he could enlist the support of his Minister, Alastair Gillespie. However, he was unsuccessful. I had no hope of influencing my own Minister because he was also in charge of Parks Canada. Luckily, Finance officials were able to state their concerns and propose alternate wording in their briefing material for the then Minister, Jean Chretien. It was reported to me later that after Parks Canada made its presentation to Cabinet Committee, Ministers from other Departments intervened in the discussion and suggested that it would be a good idea if an assessment of non-renewable resources was carried out prior to park designation. Parks Canada officials strongly disagreed. It was the intervention of a Minister from Quebec, with responsibility for a completely unrelated portfolio, that was critical. That Minister said it was indeed a good idea to assess what might be affected by a park designation. A discussion ensued, which led to a decision directing officials to revise the policy by including an amendment requiring non-renewable resource assessments. This was later approved by full Cabinet. The resulting National Park Policy (1979) states " It is the policy of the Department of Indian Affairs and Northern Development to ensure that an inventory of the non-renewable natural resource potential of areas in the Yukon and Northwest Territories be compiled prior to their formal establishment as new national parks. The fundamental qualities of the area which recommend it for national park status will be taken into account in any land use activities associated with compiling the inventory. Parks Canada will cooperate with other federal agencies responsible for carrying out such inventories." MERA was established in 1980 to carry out this policy. Membership initially included DIAND, EMR (now NRCan), and Parks Canada but was modified in 1987 to include the governments of the Yukon and Northwest Territories. Presumably, it has now been revised again to include the new government of Nunavut. The Geological Survey of Canada was given the mandate to carry out these assessments. Most Canadians would probably consider this to be a balanced and reasonable policy, except for the implication that park proposals will not be dropped merely because of high non-renewable resource potential. The history of its creation shows how important hard work, luck and timing are in the writing of policy or legislation. In this case, mid-level officials were able to overcome the disinterest of the Ministers who should have been the advocates for northern mining (DIAND and EMR). This was made possible through the intervention of Chretien (who wasn’t known for his support of resource development when he was Minister of DIAND) and another Minister who had no direct portfolio interest in the issue but thought that this type of assessment made sense as part of the park evaluation process.

October 2000 – Gangue No. 67 DANIEL ROBERT BOYLE Obituray September 11th, 2000

Daniel Robert Boyle died on June 30th, 2000, in Ottawa, Ontario, at the age of 52 after a courageous battle with cancer. He completed a B.Sc honors at Queens Uni- versity, and a Ph.D. on the geochemistry of fluorine at Imperial College in London in 1976. He also taught at Imperial College and supervised graduate students work- ing in different parts of the world. During his 25 years at the Geological Survey of Canada, he became well recognized world-wide for his research in the area of geochemistry, particularly as it relates to the origin of metals in ancient ore deposits and modern natural environments. His approach to research was to look at the total system in an holistic sense, which is a testament to his broad interests and an in- credible capacity to assimilate knowledge on diverse but related subjects. In this respect, he was a renaissance scientist of the old school, who looked at problems not from an overly specialized and narrow perspective, but from the viewpoint of someone who wanted to understand the complex interplay of different processes. He was also heavily involved in national and international science organizations and the university community. He was the incoming president of the Geological Society of the Canadian Institute of Mining and Metallurgy (CIMM), vice- president of the International Association on the Genesis of Ore Deposits (IAGOD), and associate editor of the Journal of Exploration and Mining Geology. He was involved most recently in a CIDA-sponsored project in China that focused on thallium dispersion from natural sources, because of the serious health problems many villagers are suffering. Although he is very well known as a scientist, he is most fondly remembered as a true friend and dedicated colleague. He is survived by his wife, Christ Vodden, a son, Matthew, a sister, Heather, and his parents, Bob and Marguerite Boyle.

Wayne Goodfellow

SOCIETY OF ECONOMIC GEOLOGISTS FOUNDATION STUDENT RESEARCH GRANTS - AVAILABLE IN 2001

Students of mineral resources throughout the world may apply for thesis research grants available in 2001 from the Society of Eco- nomic Geologists Foundation and the Society of Economic Geologists. The purpose of the grants is to provide partial support of master’s and doctoral thesis research for graduate students. Grants also are available to support Honors thesis research for under- graduate students. Grants from the Hugh E. McKinstry Fund are awarded to support research with a substantial field component. The Hickok-Radford Fund awards grants for field projects in arctic or sub-arctic regions. Research grants, in part funded by gifts from BHP Exploration, provide funds for research in economic geology that focuses on new descriptive data on ore deposits and mining districts, mainly outside of North America, and on topical subjects. The 2001 awards total at least $80,000. Individual grants usually range from US$500 to US$3,000 and are intended to fund specific research expenses. Awards are competitive and students must describe what the project is, why the research is important, how it is to be done, and provide a summary budget. Application forms may be obtained from the Chair, SEG Student Research Grants, 7811 Shaffer Parkway, Littleton, Colorado 80127, USA. Phone: +1 (720) 981-7882 x204; fax: +1 (720) 981-7874; E-mail: [email protected]

Forms also available on the web: www.segweb.org; Applications must be postmarked by 1 February 2001, and awards will be announced by 15 April 2001.

October 2000 – Gangue No. 67 VMS Exploration: Concepts and Case Studies Proposed University of Toronto Student Chapter of the Society of Economic Geologists Short Course: Everything you ever wanted to know about VMS Exploration March 9th, 2001 – Note PDAC starts on March 11, 2001

A 1-day Short Course focused on all aspects of exploration for VMS deposits. The morning session will be essentially conceptual and cover various aspects and models for VMS exploration. The afternoon session will be dedicated case studies, highlighting some of the more recent VMS discoveries. The following is a list of currently confirmed speakers:

Gerald Riverin Risks and Rewards of VMS Exploration: Economic Guidelines (Inmet Mining Corp.)

Tucker Barrie Heat and Fluid Flow Modeling of VMS-Forming Hydrothermal Systems: Practical Application Jim Franklin Principal tectonic settings of VMS deposits (Franklin Geosciences Ltd.) Harold Gibson Volcanic Controls on VMS Deposits: A guide in Exploration (Laurentian University) Frank Santaguida Hydrothermal Alteration Mineral Assemblages (Carleton University)

Mark Rebagliati The multiple Campo Morado precious metals-rich VMS discoveries; how they happened. (Hunter Dickinson Inc.)

For more information, please contact: Yannick Beaudoin at 416-978-0665 or Email the U of T SEG Chapter at seg@zircon.geology.utoronto.ca Fax: 416-978-3938 ICQ # 96633730

Venue: University of Toronto University College Building, room UC179 and Croft Chapter House Lunch and breaks included

Fees: $180 for industry $100 for private prospectors $25 for students

fees cover the cost for speaker accommodations, lunches and breaks

Registration deadline----Monday February 5th, 2001

Structural Atlas Project

Edited/Compiled by Alexander Cruden, Shoufa Lin and Benoît Dubé

Sponsored by Geological Association of Canada (GAC) Mineral Deposits Division (MDD) & Structural Geology and Tectonic Division (SGTD)

Preliminary Call for Contributions

Objective: To produce a well illustrated guide to the identification and interpretation of common geological structures as encoun- tered in the field by professional mineral deposits geologists, senior undergraduates and graduate students. The atlas is intended to be a companion volume to the MDD’s highly successful Alteration Atlas.

Organisation: The atlas will comprise a collection of high quality photographs (preferably in colour) accompanied by brief text descriptions and explanatory line drawings where necessary. Larger scale structural features (preferably with a relationship to an ore deposit) will be illustrated using simplified maps and cross sections. Material will be organised along fairly traditional

October 2000 – Gangue No. 67 grounds, including sections on:

• Joints, Fractures, Faults and Fault Rocks (including breccias) • Folds and Polyphase Deformation • Cleavage, Foliation and Lineation • Shear Zones and Kinematic Indicators • Primary Structures (sedimentary and intrusive)

Each major section will be introduced by a brief “theory” chapter outlining the major concepts, terminology, tectonic significance and sources of further information for each group of structures. These sections will also highlight the relevance of structural geology to ore deposit studies.

Contributors: Contributions are welcome from the entire structural community.

Call for contributions: Individuals wishing to contribute material to the atlas should contact Sandy Cruden by e-mail before Jan. 1, 2001. We are looking for first rate examples of all types of geological structure, with an emphasis on field relationships at outcrop to local (i.e., prospect and camp) scales. These examples need not be associated with an ore deposit, although good illustrations of relationships between mineralisation and deformation are also required. Please send your proposed photographs, maps and cross sections as digital thumbnails in GIF, TIF, JPEG or BMP format. If this is not possible, then send colour photocopies by regular mail. Each figure submitted should be accompanied by a brief (<100 word) description outlining what it illustrates, its location, geological setting and scale. As a guide, figures will most likely be laid out in plates of four per page, with accompanying text on the facing page, following roughly the same format as the MDD Alteration Atlas. There is no restriction to the number of photographs, maps and cross sections that you submit.

Selection of contributions: The editors will select the most suitable contributions from the first round and then compile a list of features for which further submissions are required. This list will accompany a second call for contributions in early 2001.

Acknowledgement of contributions: All material used in the atlas will be acknowledged in the accompanying text, and a list of contributors and their affiliations will be included at the beginning of the book. Contributions should be able to be listed as book chapters/pages in your cv.

Schedule: Sept. 1 2000 – Jan 1 2001: Submission of digital thumbnails and descriptions. Jan 1 2001 – March 1 2001: Review and selection of submissions, preliminary layout of atlas. Identification of material still required. March 1 2001: Contributors will be contacted and informed of their submissions that will be included in the atlas. Detailed information on the format of the final submissions will be provided at this stage. March 1 2001 – June 1 2001: Second call for contributions, this time with a list of specific examples that are still required. June 1 2001 – Sept 1 2001: Submission of all material to be completed. Editors and others to prepare theory chapters, bibli- ography, etc. Sept 1 2001 – Feb 1 2002: Layout, production and editing of camera ready copy. Feb. 1 2002: Submission of atlas to printers. May 20 2002: Publication launch at GAC-MAC 2002.

Submit all material and requests for further information to Sandy Cruden (address below). Feedback on any aspect of the atlas (i.e., suggestions for organisation, content, etc.) will be appreciated, as would offers to contribute material to theory chapters.

Prof. Sandy Cruden Dept. of Geology University of Toronto 22 Russell St Toronto, Ontario M5S 3B1 Tel. (416) 946-7284 Fax. (416) 978-3938 e-mail [email protected]

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October 2000 – Gangue No. 67 The Mineral Deposits Division of the Geological Association of Canada and the Geological Survey of Canada are please to announce the impending January 2000 release of the highly anticipated MDD Special Volume #1 on the world class Sullivan Zn-Pb Mine, British Columbia, Canada.

The final cost of the volume for sale to GAC members and the general geoscience community will not be set until the new year. All sales will be made through the GAC. www.gac.ca

October 2000 – Gangue No. 67 MEETINGS, WORKSHOPS, & FIELDTRIPS

2000 • December 15-19 – AGU Fall Meeting, San Fransisco, CA. Contact AGU Meeting Department, 2000 Florida Ave., NW, Washington, DC 20009, Tel: (202) 462-6900, Fax: (202) 328-0566, email: [email protected]

2001 • January 23-26 - 18th Annual Cordilleran Exploration Round-Up, Vancouver, BC; Contact: http://www. chamberofmines.bc.ca/rdup2001/welcome.htm • March 11-14 - Prospectors and Developers Assoc. of Canada, Annual Congress, Toronto, Ontario; www.pdac.ca • May 6-10 - Geochemistry and Exploration in Latin America. 20th International Geochemical Exploration Symposium, Santiago Chile. email: [email protected] • May 27-30 - Annual GAC-MAC meeting & North American Minerals Symposium, St. John’s, Nfld. Information: www. geosurv.gov.nf.ca; email: [email protected] • August 19-24 - Gordon Conference on Inorganic Geochemistry (Formation, Modification, and Preservation of Ore Depos- its) Proctor Academy, New Hampshire. Contact: Jeff Hedenquist, email: [email protected] • August 27-29 - The 6th Biennial Society for Geology Applied to Mineral Deposits, Mineral Deposits at the beginning of the 21st Century. Krakow, Poland. http://galaxy.uci.agh.edu.pl/~sga/ • November 5-8 - Annual Meeting of the Geological Society of America, Boston, Mass. Contact: email: meet- [email protected]; www.geosociety.org

Please submit your events to Dave Lentz at email: [email protected]

The 20th International Geochemical Exploration Symposium (IGES)

Geochemistry and Exploration: 2001 and Beyond

Santiago de Chile - May 6th to May 10th, 2001 Second Circular and call for Papers

TECHNICAL PROGRAMME - Monday May 7th to Thursday May 10th, 2001 We have assembled a diverse programme to address most exploration and environmental issues which will include many case histories including the following:

1. Exploration for concealed gold, porphyry copper and other base metal deposits 2. Geochemical Methods 3. Arid saline environment exploration geochemistry 4. Port site sea water and sea bed geochemistry 5. Exploration in deeply weathered areas emphasizing partial extractions 6. Isotope geochemistry applied to ore search 7. Industrial Minerals exploration for Lithium, Iodine, Boron, Borates and Nitrates 8. Geochemical Bridges : Environment and Exploration Applications Abstracts in digital format only are due no later than January 31st 2001.Format is 1 page, or 500 words, maximum to be sent by email. Please refer to the info on the website: www.aeg.org

NEW JOURNAL - Geochemistry: Exploration, Environment, Analysis (GEEA) See the Association of Exploration Geochemists website for more details and the Guide to Authors—Www.aeg.org

October 2000 – Gangue No. 67