GEOLEX

Summary of Citation: Puritan

Publication:
Schmidt, R.G., 1976, Geology of the Precambrian W (Lower
   Precambrian) rocks in western Gogebic County, Michigan: U.S.
   Geological Survey Bulletin, 1407, 40 p.

Usage in Publication:
Puritan Quartz Monzonite*

Modifications:	Geologic Province:	Dominant Lithology:
Named	Lake Superior region	Quartz monzonite

Summary:
Named for regionally dominant intrusive body where extensive exposures are found one mi south of town of Puritan in western Gogebic Co, northwest MI in Lake Superior region. Is main part of Puritan--Van Buskirk pluton. At north end, main body is relatively homogeneous porphyritic quartz monzonite where it intrudes Ramsay Formation (new). East and west margins are either sharp or gradational to fringing Whiskers Creek Gneiss (new); south margin is transitional with Van Buskirk Gneiss (new). Puritan is mostly pale, pinkish-gray, medium- to coarse-grained quartz monzonite with rectangular to somewhat rounded poikilitic 1-3 cm microcline phenocrysts. Grain size decreases in northern part of area and near margins of intrusive. Is of relatively simple mineral composition (mineralogic data provided). Varying colors of feldspar are due to degree of metamorphism. Geologic map. South of Whitney Creek-Palms Creek lineament all single-phase, unstriped rock mapped as Puritan. Style of contact with invaded country rock varies from simple in north to complex in south. Locally invaded by generally younger Sunset Creek Intrusive Complex (new). Is assigned a Precambrian W [Archean] age.

Summary of Citation: Puritan

Publication:
Sims, P.K., Peterman, Z.E., Prinz, W.C. and Benedict, F.C.,
   1984, Geology, geochemistry, and age of Archean and Early
   Proterozoic rocks in the Marenisco-Watersmeet area, northern
   Michigan, IN Contributions to the geology of the Lake Superior
   region: U.S. Geological Survey Professional Paper, 1292-A-B,
   54 p.

Usage in Publication:
Puritan Quartz Monzonite*

Modifications:	Geologic Province:	Dominant Lithology:
Isotopic dating	Lake Superior region

Summary:
Puritan Quartz Monzonite has Rb-Sr date of 2,650 m.y., or a Late Archean age in the Marenisco-Watersmeet area, MI, in Lake Superior region on rocks of Puritan batholith and its small associated bodies. Geologic map. Cross section. Chemical analyses.

Summary of Citation: Puritan

Publication:
Cannon, W.F., Woodruff, L.G., Nicholson, S.W. and Hedgman, C.A.,
   1996, Bedrock geologic map of the Ashland and northern part
   of the Ironwood 30' x 60' quadrangles, Wisconsin and Michigan:
   U.S. Geological Survey Miscellaneous Investigations Series
   Map, I-2566, 1 sheet, scale 1:100,000

Usage in Publication:
Puritan Quartz Monzonite*

Modifications:	Geologic Province:	Dominant Lithology:
Areal limits	Wisconsin arch

Summary:
Puritan Quartz Monzonite extended from MI into WI.