Issue 55 February 1997 PREDICTIVE METALLOGENY − “PREMET” Proposal for a new NERC Thematic Research Program in the UK Introduction The science of metallogenesis has Mantle Petrogenesis: Many mineral de- Both of these factors are critical components reached a landmark stage where there are few posits are directly or indirectly associated in ore formation, and integration of a detailed major classes of ore deposits for which a with magmatism ultimately of mantle deriva- mechanistic knowledge of plate tectonic proc- working model of their formation does not tion. And yet only a small fraction of ex- esses with an understanding of the conse- exist. This knowledge permits, in broad posed mantle-derived lithologies host ore de- quent magmatic and heat flow responses will terms, prediction of likely geological envi- posits. Recent advances in the understanding provide both a location- and magma-specific ronments for formation of specific classes of of base and precious metal behaviour in sili- indicator for mineral prospectivity. ore deposit. It may also predict relationships cate and sulphide melts can be used to predict Crustal Environment: The crustal en- to structural or tectonic features, or certain the ways in which ore-forming components vironment consists of: chemical reservoirs lithological facies. Beyond this stage, how- will behave in certain melt compositions such as the wallrock and host lithologies with ever, exploration tends to step rapidly away formed under specific conditions of mantle which magmas or fluids may have interacted; from the underpinning science. As a result, melting. Much work has yet to be done, how- fluids within these sequences; and high-per- there is often an apparent discontinuity be- ever, before a comprehensive understanding meability zones formed by structural and li- tween the logical place of mineral deposits of these processes is achieved. This work will thological features. In many cases it is not within an overall geological framework, and combine experimental studies with petrologi- clear what role the upper crustal environment the actual geology of the deposits themselves. cal and geochemical observations of natural has played in ore formation: in some cases the It is the objective of this research programme mantle products, to provide a predictive role is purely mechanical, providing a con- to integrate existing and future deposit-spe- framework for prospective magma types. venient site for magma emplacement or hy- cific information within this broader geologi- Tectonic Setting: Mantle melting drothermal fluid flow; in other cases, chemi- cal framework in such a way that the forma- events, and subsequent crustal melting, are cal interactions with wallrocks appear to play tion of ore deposits in terms of process, controlled by thermal processes occurring a vital role. Understanding the relative im- location, and size becomes both under- within the mantle, and transmitted to the crust portance of these factors in ore formation is standable and predictable. by plate motions. In many cases, the trans- essential for predictive metallogeny. Approach lithospheric permeability provided by tec- Fluid Interactions: The properties of tonic sutures and structural zones is the key hydrothermal fluids are central to mineral All mineral deposits are formed as a re- to crustal emplacement of mantle-derived transport and deposition in many systems, and sult of common geological processes, nor- magmas, and focused enhanced heat-flow. an understanding of the processes that may mally taken to an extreme or maintained over a long period of time. Moreover, for any given deposit type a number of such proc- Yellowknife Women Geoscientists Calendar esses, either working together or in sequence, are required to efficiently concentrate ore- forming components to form an economic re- source. Prediction of mineral prospectivity The Yellowknife Women Geoscientists have put together another of their (in)famous cal- requires a detailed understanding of these endars for 1997. All proceeds from the sale of these calendars goes to the Walter Gibbins various processes and their interactions, and Memorial Fund, established in 1992 in memory of the DIAND District Geologist Walter Gibbins. thus involves a multi-disciplinary approach. Funds are used to purchase scientific texts and other learning materials to promote earth science In this respect, the development of most ore education in schools throughout the Northwest Territories. forming systems is controlled by processes occurring under five broad headings: This year’s offering “Staking Our Claim to Fame: Geo Images” is selling for $10 plus $1 postage if ordering by mail, and can be ordered from: Geocalendar Fund, Bag 9100, Yellowknife, NT, X1A 2R3, or ordered via e-mail from [email protected]. February 1997 1 MEETINGS, WORKSHOPS FIELDTRIPS March 1997 (IGM). Lab prep, chemistry, optical micros- 5946415; FAX: 44-0-171-5946540; Email: copy etc. Field Trip to Neves-Corvo in the [email protected]. 9-12Prospectors & Developers Asoc of Can- Iberian Pyrite Belt, Sept 11-12. Contact: Dr. ada - International Convention & Trade Orlando C. Gaspar, IGM, Apartado 89, 4465 January 1998 Show. Royal York & Metro Toronto Con- S. Mamede de Infesta, Portugal. Tel: +351- 2-951-19-15; FAX: +351-2-951-40-40. vention Centre, Toronto, Canada. Contact 28 - 30 Exploration Methods ‘98 - Pathways PDAC 34 King St E, 9th Floor, Toronto, 10 - 15 Paleogeographical and Geodynamic to Discovery. Hotel Vancouver, Vanc. BC. M5C 2X8. Tel: 416-362-1969; FAX: 416- Conditions of Volcanic Sedimentary Ore Sponsored by the BC&YCM, SEG, BCGSB 362-0101 Formation. Miass, Russia. Commission on and GSC. This will be a special version of volcanic sedimentary ore genesis the traditional Cordilleran Roundup and April 1997 (COVSOG) of the Russian Academy of will comprise all the traditional events plus Sciences (RAN) in common with the special technical sessions and field trips on 21 - 25 EACM ‘97: East Asian Continental Russian section of IAGOD, the Urals topics of interest to economic geologists. Margin - Geology and Development. Hong branch of RAN and All Russian Geologi- Contact: BC & Yukon Chamber of Mines, Kong. Sponsored by Univ. of Hong Kong, cal Research Institute (VSEGEI). Post 840 W Hastings St., Vancouver, BC, V6C H.K. Geological Survey, & Geological So- Conference field trip (3-4 days) to the fa- 1C8. Tel: 604-681-5328; FAX: 604-681- ciety of Hong Kong. Contact: EACoM ‘97, mous Ilmensky Mineralogical Reserve, to 2363. Earth Sciences Dept, Univ. of Hong Kong, massive sulfide deposits, Fe-Mn, Cu, Mo, Pokfulam Road, Hong Kong. FAX: 852- and other ore fields of the South Urals. Of- 31 - Feb 7 The California Gold Rush 25176912; Email [email protected]. ficial languages will be English, German, Fieldtrip. Mother Lode District & Southern California Desert. Sponsored by MDD- April 27 - 30 CIM ‘97 - . New Frontiers for the and Russian. Registration fees: 200 US$ and 150 US$ for SGA and IAGOD members. SEG-BCYCM. Contact: Dani Alldrick, Next Century. Vancouver, BC. Contact: MDD Fieldtrip Coordinator, Tel: 250-952- Chantal Murphy, Meetings Dept., CIM, Contact: Prof. V.E. Popov, Sredny 74 VSEGEI, 199026 St.- Petersburg Russia; 0412; FAX: 250-952-0381; Email: 3400 de Maisonneuve Blvd. West, Suite [email protected]. 1210, Montreal, PQ, H3Z 3B8. Tel: 514- Fax +7 (812) 213 - 5738; E - mail: 939-2710; FAX: 514-939-2714. [email protected] (for V.E. Popov). 12 - 15 Yellowstone Park Fieldtrip. Sponsored March 1998 May 1997 by MDD. Organized by Rick Hutchinson, Nat’l Park Service - Yellowstone, Gary 15 - April 8 Australia-Tasmania Fieldtrip. 17 - 18 Short Course: Volcanic-Associated Wells - Inmet Mining Corp & D. Alldrick - Sponsored by MDD-SEG-BCYCM. Tour Massive Sulphide Deposits in Ancient and BC Geological Survey. Contact: D. Alldrick, organizers John Thompson, Dick Hutchin- Modern Settings: Classification, Processes MDD Fieldtrip Coordinator, Tel: 250-952- son & Dani Alldrick. Contact: D. Alldrick, & Examples. Sponsored by SEG and MDD 0412; FAX: 250-952-0381; Email: MDD Fieldtrip Coordinator, Tel: 250-952- - immediately preceding the Ottawa ‘97 [email protected]. 0412; FAX: 250-952-0381; Email: GAC-MAC Annual Meeting. Contact: T. [email protected]. Barrie or M. Hannington, GSC, 601 Booth 14 - 18 Exploration ‘97. 4th Decennial Inter- Street, Ottawa, ON, K1A 0E8. Tel: 613-947- national Conf. Geophysical & 2793 or -996-4865; FAX: 613-996-9820; Geochemical Exploration. Toronto. Work- May 1998 E mail: [email protected] r.ca, or shops Sept 8-12th. Contact: Jon Baird, [email protected]. Publicity Chair, c/o CAMESE, 101-345 18 - 20 Mineralized Porphyry-Skarn Systems Renfrew Drive, Markham, ON, L3R 9S9. - Short Course. Quebec City, PQ. Immedi- 11 - 14 NEVES CORVO Field Conference. Tel: 905-513-0046; FAX: 905-513-1834; ately prior to GAC/MAC Annual Meeting. Univ of Lisbon, Portugal. Conference will Email: [email protected]. Ab- Contact: Dave Lentz, NB Geological Sur- be organized around the Neves Corvo mine stracts by Sept 1/96 to Ian MacLeod, Chair, vey, Box 50, Bathurst, NB, E2A 3Z1. Tel: & other points of interest in the Iberian Py- Technical Prgm Comm., c/o Geosoft Inc., 506-547-2070; FAX: 506-547-7694; E- rite Belt. Contact: Geoffrey Snow, Barranca Suite 500, 204 Richmond St. W., Toronto, mail: [email protected]. Resources, c/o SEG Offie, 5808 Rapp Street ON, M5H 2G4; Email: [email protected]. #209, Littleton, CO 80120, USA. Tel: 303- 797-0332; FAX: 303-797-0417; WWW: June 1998 http://NevesCorvo.geo.fc.ul.pt. October 1997 June 29 - July 18 IAGOD/CODMUR 8th In- August 1997 20 - 23 SEG Annual Meeting with Geological ternational Platinum Symposium. Society of America. Salt Lake City, Utah. Johannesburg, South Africa. Field excur- 11 - 13 Fourth Biennial Meeting, Society of Contact: R.W. Schafer, BHP Minerals, sions and technical meeting. Contact: Dr Geology Applied to Mineral Deposits 14062 Denver West Parkway, Suite 150, C.A. Lee, PO Box 68108, Bryanston 2021, (SGA).