Frontispiece: modified from Carr,S.D., Easton, R.M., Jamieson, R.A., and Culshaw, N.G., 2000.

 Geologic transect across the Grenville Orogen of Ontario and New York. Canadian Journal of Earth Sciences, 37, 2-3, p. 193-216.
 

                    Field trip itinerary:

Map of route - from the US/Canada border to Star Lake via Gouverneur and Balmat

               Internet links to maps and notes:

        Annotated geologic map of the Grenville Structural Province - Carr et al., 2000

        Crustal Formation age map of the Grenville Structural Province by A. Dickin

        General geologic map of the Adirondack region showing ages of main rock units

        Geological highway map of the Adirondack region - Geological Highway Map - Northeastern Region (AAPG National Bicentennial Edition)

                    Legend, Grenvillian rock units:

                        YA - anorthosite; YGB - gabbro-diorite; YG - granite; YCH - charnokites; Y-UI - ultramafic rocks;

                        YGG - granite gneiss; YPG - paragneiss; YC - marbles (stromatolitic at some localities in the Balmat area);

                        YMV - amphibolites (metavolcanics); YQ - quartzites; YMI - migmatites;

                        CP = Cambrian Potsdam Sandstone unconformable on Grenville age rocks

       Other links:

DAY 2 - Geology of the Gouverneur Balmat zinc region

                Geological map of the Gouverneur - Balmat region

               The following maps,  sections, and conceptual diagrams are from 'Balmat Mine Resource and Reserve Audit', by J.E. Steers, 2003:

Geology and Mineralization, Balmat Mine by John E.Steers - click to access this report and figures.

Geological map of the Sylvia Lake Syncline, Balmat -  Fig 4-1

W-E cross-section through the Balmat area - Fig. 4-3

Table of formations, numbered as in the W-E cross section - Table 4-2

Plan map showing Balmat orebodies - Fig. 4-2

Plan map showing Balmat orebodies (Fig 4-2) and airphoto of the corresponding area

Idealized cross section illustrating the concept of 'parent/daughter' orebodies - Fig 4-4

                 Related Link:

The following is a link to a document by Michel Gauthier and Jean-Francois Lariviere concerning  non-sulphidic Franklin-type zinc silicates and oxides in the Grenville Province -  http://hercules.is.mcgill.ca/acfas72/C3402.htm :

Étude des processus dynamo-métamorphiques de bonification des gîtes de silicates et d'oxydes de zinc dans les marbres du Supergroupe de Grenville de la région de Bryson.

Abstract: L'une des principales tendances de la recherche des gîtes métallifères du zinc est aujourd'hui tournée vers des gisements non sulfurés. Pourquoi attaquer un tel sujet ? Premièrement parce que de nouvelles techniques hydrométallurgiques viennent de renouveler le potentiel commercial des minerais non sulfurés de zinc. De plus, ces minerais peuvent constituer des gisements plus riches (20 % Zn) que la majorité de leurs pendants sulfurés. Finalement, ces minerais contiennent généralement peu de plomb, de soufre et autres éléments délétères pour l'environnement. Dans la région de Bryson, nous avons trouvé localement des magnétites avec des exsolutions dendritiques de wurtzite, donnant à penser qu'elles proviennent de la déstabilisation de la franklinite. Dans ce même secteur, dans des marbres dépourvus de sulfures et de magnétite, des grains de serpentine réagissent à un réactif au zinc. Un examen approfondi à la microsonde des nodules de serpentine zincifère révèle la présence d'inclusions très fines de pyrophanite zincifère et de wurzite. Un spinel transitoire entre le pôle de l'hercynite et celui de la gahnite se présente sous forme de très rares reliques dans les nodules de serpentine. D'autres parts, la willémite s'altère également en serpentine. Elle possède la même formule chimique que l'olivine si ce n'est que le cation du zinc plutôt que du fer ou du magnésium. Nous soupçonnons alors que nous avions une paragenèse minérale semblable au gisement de Franklin (NJ) à Bryson.

Stop 1,2 - Gouverneur Talc Company talc mine  (UTM 469180, 4901641) south of Fowler (wispy stromatolitic? carbonate exposed in the pit; photographs courtesy of Phil Geusebroek ).

                 The largest volume mineral mined here is a tremolitic talc, sold under the trade names NYTAL^® and CERAMITALC^®. Chemically, tremolitic talc is magnesium silicate (Mg3Si4O10(OH)2)
Stop 3  - Wollastonite mine (UTM:469663, 4885653) entrance is located about 200 metres north of the junction (UTM: 469855, 4885301, 18T) of the  minor road leading to the mine from Highway 3,  west of Remington Corners. (Airphoto: apreming.jpg )

                Wollastonite is sold under the trade name VANSIL^®,  and chemically is calcium silicate (CaSiO3). At the Remington Corners locality it is present as coarse radiating white crystals in sea-blue calcite. The mine is located in carbonates immediately NW of the Colton shear zone which separates the carbonates from the high grade charnokitic gneisses to the east.
Stop 4  - Outcrops of inverted stromatolitic carbonate , (stromatolitic carbonate 1, stromatolitic carbonate 2 - the latter two photographs courtesy of Jim Franklin) in unit 4 (Table of Formations) at the junction of the Sylvia Lake road with the entrance road to the Balmat zinc mine (UTM 567460, 4901639).  Supposed stromatolitic structures are preserved in blocks floating in highly deformed marble.

Stop 5  - Outcrop (UTM 468945, 4902873) on the east side of highway 58  to Gouverneur from Fowler of sulphidic staurolite-bearing schist (unit 2, Table of Formations).

Stop 6  - Road-side outcrops (UTM 468256, 4904050) near Poplar Hill of migmatitic gneiss underlying the Balmat carbonate units.

J.M. McLelland, J.W. Valley, and E.J. Essene, 2001. Very high temperature, moderate pressure metamorphism in the New Russia gneiss complex, northeastern Adirondack Highlands, metamorphic aureole to the Marcy anorthosite: Discussion Can. J. Earth Sci. Vol. 38, p. 465-470.

Map of route - Tupper Lake, Au Sable Forks, Sandford Lake, and Gore Mountain regions

Geological map of the Lake Placid - Au Sable Forks region

Geological map of the Au Sable syenite - Russel, S. 2003, B.Sc thesis ( http://publish.uwo.ca/~sdrussel )

Airphoto of Au Sable Forks

Abstract: Fayalite-augite syenites are the latest intrusives in the Adirondack region of the Grenville Province (1047 ±2.2Ma from McLelland et al, 2001) ; accordingly, their petrogenesis provides insight into crustal conditions late in the Grenville Orogeny. Probable origins of these syenites are: (1) partial melt of Anorthosite-Mangerite-Charnockite-Granite suite rocks (AMCG) (McLelland et al., 2001) (2) a facies of the Lyon Mountain Gneiss (LMG) (Whitney et al., 1993).

Spatial, temporal, and geochemical association link s fayalite-augite syenites and LMG (granitic facies – a minimum temperature melt); however, lack of penetrative foliation in the Ausable syenite as well as the observation of deformed entrained enclaves of LMG requires that syenite intrusion occurred after metamorphism of the LMG.

Comparable major and trace element concentrations indicate that fayalite-augite syenites likely formed in similar crustal source regions under comparable P-T conditions. It has proven difficult to explain why fayalite-augite syenites show such high geochemical homogeneity. High temperatures of crystallization may explain anomalously high Ga contents (27-45 ppm). Whole rock and mineral compositions constrain melt temperatures ranging from 720-780^oC. Comparison of pyroxene trace element concentrations with whole rock abundances shows that whole rock content is largely a reflection of the presence of this phase.

The Rb-Sr-Ba ternary system and Harker diagrams of AMCG and LMG data illustrate increasing concentrations in refractory and incompatible elements. Fayalite-augite syenites fall high in these trends and indicate that melts formed from partial melting.

Within AMCG granitic suites, fractional crystallization is the dominant process; however, since fayalite-augite syenites are so homogeneous they are difficult to group into these trends. With limited refractory phases and inclusions, as well as geochemical homogeneity, it is proposed that fayalite-augite syenites formed from high degrees of partial melting of a refractory quartzo- feldpathic source region that was dehydrated and reduced during prior metamorphic and partial melting extraction events.

Geological map of the Newcomb - Sandford Lake Mine region

Airphoto of Sandford Lake Mine

     Archibald McIntyre sent his son John, and Duncan McMartin, to search for silver in the Adirondack Mountains.

     According to legend a young Indian led them to the site where they found large quantities of iron ore on the outskirts of Newcomb Village. They formed the Adirondack Iron & Steel Company. Some of the buildings as well as the blast furnace are still on the site. Later, the Adirondack Steel Company mine was sold to The National Lead Company who discovered titanium in the area, which was used for paints during the Second World War. The property and developed titanium site is Previously owned by NL Industries. In 2003 the property was purchased by the Open Space Institute. In 1963, The National Lead Company moved the entire Village of Tahawus to the Winebrook area in Newcomb, so they could expand their mining operations. Many of the employees retired and live in Newcomb. In 1990 the Mine closed due to economics.

                  References:

     Hayburn, M.M., 1960, Geological and geophysical investigations of the Sanford Hill orebody extension, Tahawus, New York: Unpubl. M.S. Thesis, Syracuse University, 48 p.

     Kelly, W., 1979. Chemisty and genesis of titaniferous magnetite and related ferromagnesian silicates, Sanford Lake deposits, Tahawus, New York, Ph.D. thesis, University of Massachusetts, pp. 199.

                   Related Links:

http://www.mrnfp.gouv.qc.ca/mines/quebec-minier/qc-minier-substances-ilmenite.jsp - ilmenite

Geological map of the Barton Garnet Mine region, Gore Mountain

Airphoto of Barton Mine, Gore Mountain

                  References:

http://www.science.smith.edu/departments/SEM/pages/Erica/SEM.html - very good site on the nature and petrogenesis of the garnets at the Barton Garnet mine.

http://www.science.smith.edu/departments/Geology/Min_jb/AdirodackTrip.pdf - comprehensive field description and set of references for the Barton Garnet mine based on:

                    Photographs:

Princeton (Buddington) field trip to the Adirondacks, 1962:

Barton Garnet Mine as it was in 1962

Professor Arthur Buddington, Professor Bob Hargraves, and Professor Joe Kalliokoski at the Barton Garnet Mine

(Read about Buddington connection to Orson Wells at: http://www.jd.gosling.btinternet.co.uk/wotw/radio.htm#top )

Professor David Wones resting on migmatitic paragneiss of the Grenville