Lake Superior Region:
Geology, Scenery and Minerals

The 30 colour photographs in this show depict a counter-clockwise tour of geological features around Lake Superior, the world's largest freshwater lake (see Fig. 1). The lake has an area of 82,380 km². It was part of the Mississippi drainage until the Pleistocene, and formed part of glacial lake Algonquin. The modern lake surface is 183 m above sea level, while the deepest point (406 m water depth) is 223 m below mean sea level! Starting at the Algoma district, the tour proceeds around the rocky shores of Ontario, also examining features in the hinterland to the immediate north of the lake. From the city of Thunder Bay, the tour proceeds to Duluth, Minnesota, and then east through Wisconsin to the Upper Peninsula of northern Michigan, U.S.A.

The slide show is an expansion of a project outlined in Wilson (1994), and is an on-line example of the "tutorial" content envisaged for the CD-ROM version of the MINLIB database. The images were mostly chosen from a show presented at the Bancroft Gem & Mineral Club, 10 October 2001. The first on-line version was installed on 27 October 2001. Twenty such tutorials are envisaged for the first edition: one or perhaps two examples will appear on this web site.

There are three levels of captions of progressively higher detail and complexity. The audience levels are not precisely defined, but might be described as; "junior school", "curious adult" and "specialist". Click below to take the Tour!

The following references have been selected largely from the viewpoint of the rockhound, but there is some excellent general reading here on the region, and much to interest the professional geologist. Serious students of geology, mining, hydrology and related disciplines can learn much from the Institute on Lake Superior Geology, a unique annual meeting with a strong focus on field trips. Five of the photographs displayed here were taken on ILSG trips between 1993 and 2000, and several others were snapped en route to and from these low-key but highly professional events.

N.B. The reference list has been slightly updated, but much more could be said!

AVERY,T (1973) Copper Country - God's Country: Reflections on a Unique Land and its Metal. Avery Color Studios, AuTrain, MI, reprinted 1988, 72pp.

BARR,E (1988) Silver Islet, Striking it Rich in Lake Superior. Natural Heritage/Natural History Inc., Toronto, 159pp.

BENNISON,AP (1978) Geological Highway Map: Great Lakes Region. AAPG Highway Map 11, approximately 1"=30 mile scale.

BENNISON,AP and CHENOWETH,PA (1984) Geological Highway Map: Northern Great Plains Region. AAPG Highway Map 12, approximately 1"=30 mile scale.

BORNHORST,TJ (editor) (1992) Keweenawan Copper Deposits of Western Upper Michigan. SEG Guidebook 13, 197pp.

BORNHORST,TJ and ROSE,WI (1994) Self-Guided Geological Field Trip to the Keweenaw Peninsula, Michigan. Institute on Lake Superior Geology, vol.40, part 2, 185pp.

CARD,KD, PERCIVAL,JA and SANFORD,BV (compilers) (1993) Geological atlas, Lake Nipigon, Ontario-USA. GSC Map NM-16-G, five (mostly) 1:1,000,000 scale map sheets.

CHISHOLM,B, GUTSCHE,A and FLOREN,R (1999) Superior: Under the Shadow of the Gods. Lynx Images Inc., Toronto, 2nd edition, 282+40pp.

CLARKE,DH (1978a) Copper Mines of Keweenaw No.11: Minesota Mining Company. Don H. Clarke, booklet, 28pp.

CLARKE,DH (1978b) Copper Mines of Keweenaw No.12: Mohawk Mining Company. Don H. Clarke, booklet, 28pp.

CLARKE,DH (1981) Rockhound Guide to Keweenaw County. Don H. Clarke, booklet, 28pp.

GILG,HA, LIEBETRAU,S, STAEBLER,GA and WILSON,T (editors) (2012) Amethyst: Uncommon Vintage. Lithographie, LLC, 124pp. (see especially pp.56-65).

GRESSWELL,RK and HUXLEY,A (editors) (1965) Standard Encyclopedia of the World's Rivers and Lakes. Wiedenfeld and Nicolson, London, 384pp.

HALSEY,JR (1992) Miskwabik - Red Metal. The Roles Played by Michigan's Copper in Prehistoric North America. Keweenaw County Historical Society, 20pp.

HEINRICH,EW (1976) The Mineralogy of Michigan. Michigan Department of Natural Resources, Geological Survey Division, Bull. 6, 225pp.

HUBER,NK (1983) The Geologic Story of Isle Royale National Park. USGS Bull. 1309, 66pp., reprinted by Avery Color Studios, AuTrain, MI.

KISSIN,S (2012) Thunder Bay amethyst mine. Institute on Lake Superior Geology, volume 58 part 2, 219pp., trip 6, 82-92, Thunder Bay, ON.

LEFOLII,K (1987) Claims: Adventures in the Gold Trade. Key Porter Books Ltd, 264pp.

LYNCH,B and LYNCH,D (2008) Rocks & Minerals: A Field Guide to the Lake Superior Area. Adventure Publications Inc., Cambridge, MN, 208pp. [attractive pocket guide, very useful for rockhounds, especially for agate varieties - covers MI, WI and MN, but not ON].

MONETTE,CJ (1996) Baltic, Michigan. Greenlee Printing Company, Calumet, MI, 128pp.

OLSON,DK (1986) Michigan silver: native silver occurrences in the copper mines of Upper Michigan. Mineral.Record 17 no.1, 37-48.

ONTARIO GEOLOGICAL SURVEY (1980) Geological Highway Map, Northern Ontario. OGS map 2440.

ONTARIO GEOLOGICAL SURVEY (1991a) Bedrock geology of Ontario, west-central sheet. OGS map 2542, 1:1,000,000 scale.

ONTARIO GEOLOGICAL SURVEY (1991b) Bedrock geology of Ontario, east-central sheet. OGS map 2543, 1:1,000,000 scale.

PYE,EG (1968) Geology and Scenery: Rainy Lake and East to Lake Superior. ODM Geol. Guide Book 1, 118pp.

PYE,EG (1997) Roadside geology of Ontario: North Shore of Lake Superior. OGS Rock On Series 2, 164pp. [update and revision of the author's "Geology and Scenery: North Shore of Lake Superior", ODM Geol. Guide Book 2, 148pp., 1969].

ROSE,WI (1994) Volcanic Geology of Eastern Isle Royale, Michigan. Institute on Lake Superior Geology, vol.40, part 3, 51pp.

SANTAGUIDA,F (2001) Precambrian geology compilation series - Thunder Bay sheet. OGS map 2664, 1:250,000 scale.

SMITH,P (1986) Harvest from the Rock. Macmillan of Canada, Toronto, 346pp.

VOS,MA (1976) Amethyst Deposits of Ontario. ODM Geol.Guidebook 5, 99pp.

WILKINS,C (1997) Breakfast at the Hoito and Other Adventures in the Boreal Heartland. Natural Heritage Books, Toronto, 182pp.

WILSON,GC (1994) Making the most of it: combining field, microscopic and bibliographic findings to interpret showings around Lake Superior. Abs. 40th Annual Meeting, Institute on Lake Superior Geology, vol.40, part 1, 84pp., 75-76, Houghton, MI.

WILSON,ML and DYL,SJ (1992) The Michigan copper country. Mineral.Record 23 no.2, 1-72.

WILSON,WE (1986) Famous mineral localities: the Silver Islet mine, Ontario. Mineral.Record 17 no.1, 49-60.