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Map showing publication footprint
  • Usage in publication:
    • Siemens Creek Formation*
  • Modifications:
    • Named
  • Dominant lithology:
    • Basalt
    • Andesite
  • AAPG geologic province:
    • Wisconsin arch
Publication:

Hubbard, H.A., 1975, Lower Keweenawan volcanic rocks of Michigan and Wisconsin: U.S. Geological Survey Journal of Research, v. 3, no. 5, p. 529-541.


Summary:

Named as a formation in Powder Mill Group (new). Named for Siemens Creek, west of Bessemer, Gogebic Co., northwestern MI (upper peninsula). Occurs in an area stretching from Ironwood, MI, westward to Mellen, WI, where it thins out. Underlies a prominent east-west body of knobby hills north of U.S. Hwy 2 in MI. Consists of olive-gray to dark-greenish-gray fine-grained basalt; also includes andesite. Mottled by patches of chlorite. Thickness is 4,400 ft near Ironwood, MI. Average thickness of flows is 9 ft but can be much thicker; basal flows measured at 115 and 175 ft. Flow tops are pahoehoe with very low relief and 5 percent vesicles. Conformably overlies Bessemer Quartzite (revised); unconformably(?) underlies Kallander Creek Formation (new). Report includes geologic map and correlation chart. Age is Precambrian Y (middle Keweenawan).

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Siemens Creek Formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Wisconsin arch
Publication:

Cannon, W.F., 1986, Bedrock geologic map of the Iron River 1 degree x 2 degrees quadrangle, Michigan and Wisconsin: U.S. Geological Survey Miscellaneous Investigations Series Map, I-1360-B, 1 sheet, scale 1:250,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_9158.htm]


Summary:

Powder Mill Group and its lower Siemens Creek Formation and upper Kallander Creek Formation assigned to Keweenawan Supergroup.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Siemens Creek Volcanics*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Wisconsin arch
Publication:

Cannon, W.F., Nicholson, S.W., Woodruff, L.G., Hedgman, C.A., and Shulz, K.J., 1995, Geologic map of the Ontonagon and part of the Wakefield 30' x 60' quadrangles, Michigan: U.S. Geological Survey Miscellaneous Investigations Series Map, I-2499, 1 sheet, scale 1:100,000


Summary:

Revised the Siemens Creek to the Siemens Creek Volcanics to maintain consistency with similar Middle Proterozoic continental volcanic sequences in the Lake Superior region.

Source: GNU records (USGS DDS-6; Reston GNULEX).


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Asterisk (*) indicates published by U.S. Geological Survey authors.

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